{"id":376,"date":"2020-08-13T20:18:48","date_gmt":"2020-08-13T20:18:48","guid":{"rendered":"https:\/\/brooksidepress.org\/basic_obgyn\/?page_id=376"},"modified":"2020-08-13T20:18:48","modified_gmt":"2020-08-13T20:18:48","slug":"prenatal-care","status":"publish","type":"page","link":"https:\/\/brooksidepress.org\/pa_obgyn\/advanced-training\/prenatal-care\/","title":{"rendered":"Prenatal Care"},"content":{"rendered":"<p><iframe loading=\"lazy\" src=\"https:\/\/www.youtube.com\/embed\/V3kYV2tUqgY\" width=\"560\" height=\"315\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><span data-mce-type=\"bookmark\" style=\"display: inline-block; width: 0px; overflow: hidden; line-height: 0;\" class=\"mce_SELRES_start\">\ufeff<\/span><\/iframe><\/p>\n<p>Duration 9:32<\/p>\n<input type='hidden' bg_collapse_expand='69e9b5545c2c59037957405' value='69e9b5545c2c59037957405'><input type='hidden' id='bg-show-more-text-69e9b5545c2c59037957405' value='Show Transcript'><input type='hidden' id='bg-show-less-text-69e9b5545c2c59037957405' value='Hide Transcript'><button id='bg-showmore-action-69e9b5545c2c59037957405' class='bg-showmore-plg-button bg-blue-button  '   style=\" color:#fcf7f7;\">Show Transcript<\/button><div id='bg-showmore-hidden-69e9b5545c2c59037957405' ><\/p>\n<p>My name is Dr. Jan Eperjesi.<br \/>\n00:02<br \/>\nI&#8217;m a resident in obstetrics<br \/>\n00:03<br \/>\nand gynecology<br \/>\n00:04<br \/>\nat Duke University.<br \/>\n00:06<br \/>\nThis presentation<br \/>\n00:07<br \/>\nis about nutrition in pregnancy.<br \/>\n00:09<br \/>\n00:12<br \/>\nFor this presentation<br \/>\n00:13<br \/>\non nutrition and pregnancy,<br \/>\n00:15<br \/>\nthere are four learning<br \/>\n00:16<br \/>\nobjectives.<br \/>\n00:17<br \/>\nNumber one is to learn<br \/>\n00:19<br \/>\nthe recommendations for weight<br \/>\n00:20<br \/>\ngain in pregnancy.<br \/>\n00:22<br \/>\nNumber two is to appreciate<br \/>\n00:23<br \/>\nmaternal and fetal risks<br \/>\n00:25<br \/>\nassociated<br \/>\n00:25<br \/>\nwith excessive or inadequate<br \/>\n00:27<br \/>\nweight gain in pregnancy.<br \/>\n00:29<br \/>\nNumber three is to appreciate<br \/>\n00:30<br \/>\ntypical weight loss<br \/>\n00:31<br \/>\nafter pregnancy.<br \/>\n00:33<br \/>\nNumber four is to provide<br \/>\n00:35<br \/>\ninformation<br \/>\n00:35<br \/>\nabout caloric intake, protein<br \/>\n00:37<br \/>\nsources, mercury toxicity<br \/>\n00:39<br \/>\nfrom certain fish,<br \/>\n00:41<br \/>\niron requirements, folic acid,<br \/>\n00:44<br \/>\nvitamin A, calcium, caffeine,<br \/>\n00:47<br \/>\nand pica.<br \/>\n00:47<br \/>\n00:50<br \/>\nThis chart shows the recommended<br \/>\n00:52<br \/>\nweight gain in pregnancy<br \/>\n00:53<br \/>\nfor different body mass indexes.<br \/>\n00:56<br \/>\nIn 1990, the Institute<br \/>\n00:58<br \/>\nof Medicine recommended a weight<br \/>\n00:59<br \/>\ngain of 25 to 35 pounds or 11.5<br \/>\n01:03<br \/>\nto 16 kilograms<br \/>\n01:04<br \/>\nfor women<br \/>\n01:05<br \/>\nwith a normal pre-pregnancy body<br \/>\n01:06<br \/>\nmass index.<br \/>\n01:09<br \/>\nThe range for twin pregnancy<br \/>\n01:11<br \/>\nis 35 to 45 pounds or 16 to 20<br \/>\n01:14<br \/>\nkilograms.<br \/>\n01:15<br \/>\nYoung adolescents that have had<br \/>\n01:17<br \/>\nless than two periods<br \/>\n01:18<br \/>\nafter their first menses<br \/>\n01:20<br \/>\nshould strive for gains<br \/>\n01:21<br \/>\nat the upper end of this range.<br \/>\n01:23<br \/>\nShorter women, meaning women<br \/>\n01:25<br \/>\nless than 62 inches<br \/>\n01:27<br \/>\nor 157 centimeters in height,<br \/>\n01:29<br \/>\nshould strive for gains<br \/>\n01:31<br \/>\nat the lower end of this range.<br \/>\n01:33<br \/>\nFor a body mass index less<br \/>\n01:34<br \/>\nthan 19.8, a greater overall<br \/>\n01:37<br \/>\nweight gain is recommended.<br \/>\n01:39<br \/>\nFor higher BMIs, the recommended<br \/>\n01:41<br \/>\nweight gain is between 15 to 25<br \/>\n01:43<br \/>\npounds or seven to 11.5<br \/>\n01:45<br \/>\nkilograms.<br \/>\n01:46<br \/>\n01:50<br \/>\nThe current recommendations<br \/>\n01:51<br \/>\nfor adequate weight gain<br \/>\n01:52<br \/>\nare from the Institute<br \/>\n01:53<br \/>\nof Medicine in 1990.<br \/>\n01:55<br \/>\nThe rationale<br \/>\n01:56<br \/>\nfor these recommendations<br \/>\n01:57<br \/>\naims to prevent pre-term birth<br \/>\n01:59<br \/>\nand fetal growth restriction,<br \/>\n02:01<br \/>\nwhich are associated<br \/>\n02:02<br \/>\nwith inadequate weight gain.<br \/>\n02:04<br \/>\nInterestingly, however,<br \/>\n02:06<br \/>\nthe current focus<br \/>\n02:07<br \/>\nis on the obesity epidemic.<br \/>\n02:09<br \/>\nObesity is associated<br \/>\n02:10<br \/>\nwith significantly<br \/>\n02:11<br \/>\nincreased risk<br \/>\n02:12<br \/>\nfor gestational hypertension,<br \/>\n02:14<br \/>\npreeclampsia,<br \/>\n02:15<br \/>\ngestational diabetes,<br \/>\n02:17<br \/>\nmacrosommia, and cesarean<br \/>\n02:18<br \/>\ndelivery.<br \/>\n02:20<br \/>\nStudies have shown<br \/>\n02:21<br \/>\nthat in obese pregnant women,<br \/>\n02:23<br \/>\nthose who gained less than 15<br \/>\n02:24<br \/>\npounds<br \/>\n02:25<br \/>\nhad the lowest rates<br \/>\n02:26<br \/>\nof pre-eclampsia,<br \/>\n02:27<br \/>\nlarge for gestational age<br \/>\n02:29<br \/>\ninfants, and cesarean delivery.<br \/>\n02:31<br \/>\nOther studies have shown<br \/>\n02:33<br \/>\nthat women<br \/>\n02:33<br \/>\nwith normal pre-pregnancy body<br \/>\n02:35<br \/>\nmass indexes<br \/>\n02:36<br \/>\nwho gain less than 25 pounds<br \/>\n02:38<br \/>\nduring pregnancy, also<br \/>\n02:40<br \/>\nhad a lower risk<br \/>\n02:40<br \/>\nfor pre-eclampsia,<br \/>\n02:42<br \/>\nfailed induction,<br \/>\n02:43<br \/>\ncephalopelvic disproportion,<br \/>\n02:45<br \/>\ncesarean delivery, and large<br \/>\n02:47<br \/>\nfor gestational age infants.<br \/>\n02:48<br \/>\n02:52<br \/>\nMost, but not all, of the weight<br \/>\n02:53<br \/>\ngain during pregnancy<br \/>\n02:55<br \/>\nis lost during and immediately<br \/>\n02:57<br \/>\nafter delivery.<br \/>\n02:59<br \/>\nIn women whose average weight<br \/>\n03:01<br \/>\ngain is 29 pounds<br \/>\n03:02<br \/>\nduring pregnancy, approximately<br \/>\n03:04<br \/>\n12 pounds is lost at delivery.<br \/>\n03:07<br \/>\nIn the next two weeks<br \/>\n03:07<br \/>\nafter delivery, there<br \/>\n03:09<br \/>\nis an additional nine pounds<br \/>\n03:10<br \/>\nof weight loss.<br \/>\n03:11<br \/>\nA further six pounds is then<br \/>\n03:13<br \/>\nlost between two weeks and six<br \/>\n03:14<br \/>\nmonths postpartum.<br \/>\n03:16<br \/>\nOverall, the more weight gain<br \/>\n03:18<br \/>\nduring pregnancy, the more that<br \/>\n03:20<br \/>\nis lost post-partum.<br \/>\n03:22<br \/>\nInterestingly, however, there<br \/>\n03:23<br \/>\nis no relationship<br \/>\n03:24<br \/>\nbetween pre-pregnancy body mass<br \/>\n03:26<br \/>\nindex or prenatal weight gain<br \/>\n03:29<br \/>\nand weight retention.<br \/>\n03:30<br \/>\n03:33<br \/>\nTo the basic protein needs<br \/>\n03:35<br \/>\nof the non-pregnant woman<br \/>\n03:36<br \/>\nare the added demands for growth<br \/>\n03:38<br \/>\nand remodeling of the fetus,<br \/>\n03:40<br \/>\nplacenta, uterus, and breasts,<br \/>\n03:42<br \/>\nas well as increased blood<br \/>\n03:43<br \/>\nvolume.<br \/>\n03:44<br \/>\nDuring the second half<br \/>\n03:45<br \/>\nof pregnancy,<br \/>\n03:46<br \/>\napproximately 1,000 grams<br \/>\n03:48<br \/>\nof protein are deposited<br \/>\n03:49<br \/>\namounting to five to sic grams<br \/>\n03:51<br \/>\nper day.<br \/>\n03:53<br \/>\nThe concentrations of most<br \/>\n03:54<br \/>\namino acids in maternal plasma<br \/>\n03:56<br \/>\nfall markedly.<br \/>\n03:58<br \/>\nPreferably, most protein should<br \/>\n03:59<br \/>\nbe supplied from animal sources<br \/>\n04:01<br \/>\nsuch as meat, milk, eggs,<br \/>\n04:03<br \/>\ncheese, poultry, and fish<br \/>\n04:05<br \/>\nbecause they provide amino acids<br \/>\n04:06<br \/>\nin optimal combinations.<br \/>\n04:09<br \/>\nMilk and dairy products have<br \/>\n04:10<br \/>\nlong been considered nearly<br \/>\n04:11<br \/>\nideal sources of nutrients,<br \/>\n04:13<br \/>\nespecially protein and calcium,<br \/>\n04:15<br \/>\nfor pregnant or lactating women.<br \/>\n04:18<br \/>\nFish are an excellent source<br \/>\n04:19<br \/>\nof protein,<br \/>\n04:20<br \/>\nare low in saturated fats,<br \/>\n04:22<br \/>\nand contain omega 3 fatty acids.<br \/>\n04:25<br \/>\nBecause nearly all fish<br \/>\n04:26<br \/>\nand shellfish contain trace<br \/>\n04:28<br \/>\namounts of mercury,<br \/>\n04:29<br \/>\npregnant and lactating women<br \/>\n04:31<br \/>\nare advised to avoid<br \/>\n04:32<br \/>\nspecific types of fish<br \/>\n04:33<br \/>\nwith potentially high<br \/>\n04:34<br \/>\nmethyl mercury levels.<br \/>\n04:36<br \/>\nThese include shark, swordfish,<br \/>\n04:38<br \/>\nKing mackerel, and tile fish.<br \/>\n04:41<br \/>\nIt is further recommended<br \/>\n04:43<br \/>\nthat pregnant women ingest<br \/>\n04:44<br \/>\nno more than 12 ounces or two<br \/>\n04:46<br \/>\nservings of canned tuna<br \/>\n04:48<br \/>\nper week.<br \/>\n04:49<br \/>\nAnd no more than six ounces<br \/>\n04:50<br \/>\nof albacore or white tuna.<br \/>\n04:53<br \/>\nIf the mercury content<br \/>\n04:55<br \/>\nof locally caught fish<br \/>\n04:56<br \/>\nis unknown, then overall fish<br \/>\n04:58<br \/>\nconsumption should be limited<br \/>\n04:59<br \/>\nto six ounces per week.<br \/>\n05:01<br \/>\n05:04<br \/>\nWith respect to folic acid,<br \/>\n05:06<br \/>\ngreater than 50%<br \/>\n05:07<br \/>\nof all neural-tube defects<br \/>\n05:08<br \/>\ncan be prevented<br \/>\n05:09<br \/>\nwith daily intake of 400<br \/>\n05:11<br \/>\nmicrograms of folic acid<br \/>\n05:13<br \/>\nthroughout the pre-conceptual<br \/>\n05:14<br \/>\nperiod.<br \/>\n05:15<br \/>\nThe Center for Disease Control<br \/>\n05:17<br \/>\nin 2004<br \/>\n05:19<br \/>\nestimated that the number<br \/>\n05:20<br \/>\nof pregnancies effected<br \/>\n05:21<br \/>\nby neural tube defects<br \/>\n05:22<br \/>\nhas decreased from 4,000<br \/>\n05:24<br \/>\npregnancies per year<br \/>\n05:25<br \/>\nto approximately 3,000 per year<br \/>\n05:27<br \/>\nsince mandatory fortification<br \/>\n05:29<br \/>\nof cereal products<br \/>\n05:30<br \/>\nwith folic acid in 1998.<br \/>\n05:33<br \/>\nBy adding 140 micrograms<br \/>\n05:35<br \/>\nto folic acid<br \/>\n05:37<br \/>\nto each 100 grams of grain<br \/>\n05:38<br \/>\nproducts, the intake<br \/>\n05:40<br \/>\nof folic acid by women<br \/>\n05:42<br \/>\nof childbearing age<br \/>\n05:43<br \/>\nmay be increased by 100<br \/>\n05:45<br \/>\nmicrograms per day.<br \/>\n05:47<br \/>\nHowever,<br \/>\n05:48<br \/>\nbecause nutritional sources<br \/>\n05:49<br \/>\nalone are insufficient,<br \/>\n05:50<br \/>\nfolic acid supplementation<br \/>\n05:52<br \/>\nis still recommended.<br \/>\n05:54<br \/>\nFor those women<br \/>\n05:55<br \/>\nwith a prior child<br \/>\n05:56<br \/>\nwith a neural-tube effect,<br \/>\n05:58<br \/>\nthe recurrence risk, which<br \/>\n05:59<br \/>\nis approximately 2% to 5%,<br \/>\n06:01<br \/>\ncan be reduced by more than 70%<br \/>\n06:03<br \/>\nwith daily folic acid<br \/>\n06:05<br \/>\nsupplements of four milligrams<br \/>\n06:06<br \/>\nper day<br \/>\n06:07<br \/>\nin the month before conception<br \/>\n06:09<br \/>\nand during the first trimester.<br \/>\n06:11<br \/>\nNote the difference between 400<br \/>\n06:13<br \/>\nmicrograms for women<br \/>\n06:15<br \/>\nwith no prior history<br \/>\n06:16<br \/>\nof a neural-tube defect<br \/>\n06:17<br \/>\nversus four milligrams<br \/>\n06:18<br \/>\nif there is a history<br \/>\n06:19<br \/>\nof a neural-tube defects.<br \/>\n06:21<br \/>\n06:24<br \/>\nWith the exception of iron,<br \/>\n06:25<br \/>\npractically all diets that<br \/>\n06:27<br \/>\nsupply sufficient calories<br \/>\n06:28<br \/>\nfor appropriate weight gain<br \/>\n06:30<br \/>\nwill contain enough materials<br \/>\n06:32<br \/>\nto prevent deficiency<br \/>\n06:33<br \/>\nif iodized foods are ingested.<br \/>\n06:36<br \/>\n300 milligrams of iron<br \/>\n06:38<br \/>\nis transferred to the fetus<br \/>\n06:39<br \/>\nand placenta.<br \/>\n06:40<br \/>\n500 milligrams is incorporated<br \/>\n06:42<br \/>\ninto the expanding<br \/>\n06:43<br \/>\nmaternal hemoglobin mass.<br \/>\n06:45<br \/>\nNearly all is used<br \/>\n06:46<br \/>\nafter mid-pregnancy.<br \/>\n06:49<br \/>\nThe pregnant woman may benefit<br \/>\n06:50<br \/>\nfrom 60 to 100 milligrams<br \/>\n06:51<br \/>\nof iron per day<br \/>\n06:52<br \/>\nif she is large, has<br \/>\n06:54<br \/>\ntwin fetuses,<br \/>\n06:55<br \/>\nbegins supplementation late<br \/>\n06:56<br \/>\nin pregnancy,<br \/>\n06:58<br \/>\ntakes iron irregularly,<br \/>\n06:59<br \/>\nor has depressed hemoglobin<br \/>\n07:01<br \/>\nlevels.<br \/>\n07:02<br \/>\nWith respect to calcium,<br \/>\n07:03<br \/>\nmost maternal calcium is in bone<br \/>\n07:06<br \/>\nand can be readily mobilized<br \/>\n07:07<br \/>\nfor fetal growth.<br \/>\n07:09<br \/>\nThere is also increased calcium<br \/>\n07:10<br \/>\nabsorption by the intestine<br \/>\n07:13<br \/>\nand progressive retention<br \/>\n07:14<br \/>\nthroughout pregnancy.<br \/>\n07:14<br \/>\n07:18<br \/>\nVitamin A is associated<br \/>\n07:19<br \/>\nwith birth defects<br \/>\n07:20<br \/>\nat very high doses in the range<br \/>\n07:22<br \/>\nof 10,000 to 50,000<br \/>\n07:23<br \/>\ninternational units daily.<br \/>\n07:26<br \/>\nThere is no vitamin A toxicity,<br \/>\n07:28<br \/>\nhowever, with a beta carotene<br \/>\n07:29<br \/>\nprecursor of vitamin A that<br \/>\n07:31<br \/>\nis found in fruits<br \/>\n07:32<br \/>\nand vegetables.<br \/>\n07:34<br \/>\nThe American College<br \/>\n07:34<br \/>\nof Obstetricians<br \/>\n07:35<br \/>\nand Gynecologists<br \/>\n07:36<br \/>\ndoes not recommend<br \/>\n07:37<br \/>\nsupplementation of vitamin A<br \/>\n07:38<br \/>\nbecause intake in the United<br \/>\n07:40<br \/>\nStates is adequate.<br \/>\n07:42<br \/>\nHowever, in developing<br \/>\n07:43<br \/>\ncountries, vitamin A deficiency<br \/>\n07:45<br \/>\nis an endemic nutrition problem.<br \/>\n07:48<br \/>\nIt causes night blindness<br \/>\n07:49<br \/>\nin pregnant women<br \/>\n07:50<br \/>\nand is associated with increased<br \/>\n07:51<br \/>\nrisk of anemia and pre-term<br \/>\n07:53<br \/>\nbirth.<br \/>\n07:54<br \/>\nIt is estimated six 6 million<br \/>\n07:56<br \/>\npregnant women suffer from night<br \/>\n07:57<br \/>\nblindness, secondary to vitamin<br \/>\n07:59<br \/>\nA deficiency.<br \/>\n07:59<br \/>\n08:03<br \/>\nThe American Dietetic<br \/>\n08:04<br \/>\nAssociation recommends<br \/>\n08:05<br \/>\nthat caffeine intake<br \/>\n08:06<br \/>\nin pregnancy<br \/>\n08:07<br \/>\nbe limited to less than 300<br \/>\n08:08<br \/>\nmilligrams per day<br \/>\n08:10<br \/>\nor about three five ounce cups<br \/>\n08:12<br \/>\nof coffee.<br \/>\n08:13<br \/>\nHowever, only extremely high<br \/>\n08:15<br \/>\nlevels of caffeine<br \/>\n08:16<br \/>\nequivalent to greater than five<br \/>\n08:18<br \/>\ncups of coffee per day,<br \/>\n08:20<br \/>\nmay have possible association<br \/>\n08:21<br \/>\nwith spontaneous abortion.<br \/>\n08:24<br \/>\nAdverse outcomes related<br \/>\n08:25<br \/>\nto caffeine are controversial.<br \/>\n08:27<br \/>\nThese include possible low birth<br \/>\n08:29<br \/>\nweight, fetal growth<br \/>\n08:30<br \/>\nrestriction,<br \/>\n08:31<br \/>\nand pre-term delivery.<br \/>\n08:33<br \/>\nOne study showed that if greater<br \/>\n08:35<br \/>\nthan 200 milligrams of caffeine<br \/>\n08:37<br \/>\nthroughout pregnancy<br \/>\n08:38<br \/>\nwas consumed,<br \/>\n08:39<br \/>\nthere was an increased odds<br \/>\n08:40<br \/>\nratio of 1.4 for fetal growth<br \/>\n08:43<br \/>\nrestriction.<br \/>\n08:43<br \/>\n08:47<br \/>\nPica is defined as craving<br \/>\n08:49<br \/>\nof pregnant women<br \/>\n08:50<br \/>\nfor strange foods,<br \/>\n08:51<br \/>\nsuch as starch and sourdough<br \/>\n08:54<br \/>\nor non-food items,<br \/>\n08:55<br \/>\nfor example, ice, starch,<br \/>\n08:57<br \/>\nor clay.<br \/>\n08:58<br \/>\nThere is a 4% prevalence of pica<br \/>\n09:00<br \/>\nin the second trimester.<br \/>\n09:03<br \/>\nPica may be triggered<br \/>\n09:04<br \/>\nby severe iron deficiency,<br \/>\n09:06<br \/>\nbut the corollary statement<br \/>\n09:07<br \/>\nis not necessarily true.<br \/>\n09:10<br \/>\nAll women with pica<br \/>\n09:11<br \/>\nare not necessarily iron<br \/>\n09:12<br \/>\ndeficient.<br \/>\n09:14<br \/>\nInterestingly, pre-term delivery<br \/>\n09:16<br \/>\nat less than 35 weeks<br \/>\n09:18<br \/>\nis twice as high in women<br \/>\n09:19<br \/>\nwith pica.<\/p>\n<p><\/div>\n<p><\/p>\n<input type='hidden' bg_collapse_expand='69e9b5545e74d2040934519' value='69e9b5545e74d2040934519'><input type='hidden' id='bg-show-more-text-69e9b5545e74d2040934519' value='Current Nutritional Guidelines'><input type='hidden' id='bg-show-less-text-69e9b5545e74d2040934519' value='Close'><button id='bg-showmore-action-69e9b5545e74d2040934519' class='bg-showmore-plg-button bg-red-button  '   style=\" color:#faf7f7;\">Current Nutritional Guidelines<\/button><div id='bg-showmore-hidden-69e9b5545e74d2040934519' ><\/p>\n<p>The most current Institute of Medicine of Guidelines in Pregnancy are:<\/p>\n<p><a href=\"https:\/\/brooksidepress.org\/basic_obgyn\/wp-content\/uploads\/2020\/08\/IOM-GUIDELINES-2009.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-459 aligncenter\" src=\"https:\/\/brooksidepress.org\/basic_obgyn\/wp-content\/uploads\/2020\/08\/IOM-GUIDELINES-2009-300x225.jpg\" alt=\"\" width=\"300\" height=\"225\" title=\"\"><\/a><\/p>\n<p><\/div>\n<hr \/>\n<p><iframe loading=\"lazy\" src=\"https:\/\/www.youtube.com\/embed\/gt3MTl8VH_s\" width=\"560\" height=\"315\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>Duration 18:47<\/p>\n<input type='hidden' bg_collapse_expand='69e9b5545eb6a3054918913' value='69e9b5545eb6a3054918913'><input type='hidden' id='bg-show-more-text-69e9b5545eb6a3054918913' value='Show Transcript'><input type='hidden' id='bg-show-less-text-69e9b5545eb6a3054918913' value='Hide Transcript'><button id='bg-showmore-action-69e9b5545eb6a3054918913' class='bg-showmore-plg-button bg-blue-button  '   style=\" color:#fcf7f7;\">Show Transcript<\/button><div id='bg-showmore-hidden-69e9b5545eb6a3054918913' ><\/p>\n<p>00:07<br \/>\nhello everyone this is Chris miranski<br \/>\n00:09<br \/>\nand this video will cover screening<br \/>\n00:11<br \/>\nduring pregnancy I&#8217;d like to thank dr.<br \/>\n00:13<br \/>\nDeborah Feldman for her contributions to<br \/>\n00:15<br \/>\nthis video the goals of this video are<br \/>\n00:18<br \/>\nas follows we will review some of the<br \/>\n00:21<br \/>\nfoundational principles related to<br \/>\n00:22<br \/>\nscreening tests we will then discuss the<br \/>\n00:25<br \/>\nmore common end employees in neural tube<br \/>\n00:27<br \/>\ndefects that can be identified through<br \/>\n00:28<br \/>\nearly pregnancy screening we will<br \/>\n00:31<br \/>\nintroduce serum and ultrasound screening<br \/>\n00:33<br \/>\nthrough the use of alpha-fetoprotein to<br \/>\n00:35<br \/>\ndetect open neural tube defects we will<br \/>\n00:38<br \/>\nunderstand the strengths and limitations<br \/>\n00:39<br \/>\nof first and second trimester serum and<br \/>\n00:41<br \/>\nultrasound screening then finally we<br \/>\n00:43<br \/>\nwill describe cell-free DNA and its role<br \/>\n00:45<br \/>\nin pregnancy screening so first a review<br \/>\n00:48<br \/>\nof the important concepts around<br \/>\n00:50<br \/>\nscreening tests screening tests are not<br \/>\n00:52<br \/>\ndesigned to be diagnostic people is<br \/>\n00:54<br \/>\nsuspicious or positive findings must be<br \/>\n00:57<br \/>\nreferred for a diagnosis and treatment<br \/>\n00:59<br \/>\ndiagnostic tests tend to be more complex<br \/>\n01:01<br \/>\ntime-consuming and costly and diagnostic<br \/>\n01:05<br \/>\ntests should be reserved when signs<br \/>\n01:07<br \/>\nsymptoms or positive screening tests<br \/>\n01:09<br \/>\nwarrant further investigation a good<br \/>\n01:13<br \/>\nscreening test has high sensitivity a<br \/>\n01:15<br \/>\nlow false positive rate detection is<br \/>\n01:17<br \/>\nbest if it can be in the pre-symptomatic<br \/>\n01:20<br \/>\nperiod screening tests should have an<br \/>\n01:23<br \/>\nintervention that improves with earlier<br \/>\n01:25<br \/>\ndetection and there needs to be cost<br \/>\n01:27<br \/>\neffective important terms to understand<br \/>\n01:30<br \/>\nwhen it comes to describing and talking<br \/>\n01:32<br \/>\nabout screening tests include<br \/>\n01:33<br \/>\nsensitivity specificity positive and<br \/>\n01:36<br \/>\nnegative predictive value and the false<br \/>\n01:37<br \/>\npositive rate and I&#8217;m going to go over<br \/>\n01:39<br \/>\nthose individually sensitivity is the<br \/>\n01:42<br \/>\nprobability that a person with a disease<br \/>\n01:44<br \/>\nwill be correctly identified by a<br \/>\n01:45<br \/>\nscreening test as having the disease<br \/>\n01:47<br \/>\nthis is also known as the detection ring<br \/>\n01:50<br \/>\nspecificity is the probability that a<br \/>\n01:52<br \/>\nperson without a disease will be<br \/>\n01:54<br \/>\ncorrectly identified by a screening test<br \/>\n01:55<br \/>\nas not having the disease the positive<br \/>\n01:59<br \/>\npredictive value is the probability that<br \/>\n02:00<br \/>\na person with a positive screening test<br \/>\n02:02<br \/>\nactually has the disease and the<br \/>\n02:04<br \/>\nnegative predictive value is the<br \/>\n02:06<br \/>\nprobability that a person with a<br \/>\n02:07<br \/>\nnegative screening test does not have<br \/>\n02:09<br \/>\ndisease<br \/>\n02:09<br \/>\nfinally the false positive rate is the<br \/>\n02:12<br \/>\nnumber of people in the population with<br \/>\n02:14<br \/>\na pause<br \/>\n02:14<br \/>\ntest who do not have the disease and<br \/>\n02:16<br \/>\nwhen the incidence of disease in<br \/>\n02:18<br \/>\nquestion is small the false positive<br \/>\n02:21<br \/>\nrate approaches the screen positive rate<br \/>\n02:23<br \/>\nso talking about screening tests they<br \/>\n02:27<br \/>\nare best when there is a large<br \/>\n02:29<br \/>\ndifference in normal versus abnormal<br \/>\n02:31<br \/>\nvalues and this would give a high<br \/>\n02:33<br \/>\ndetection rate with the low false<br \/>\n02:34<br \/>\npositive rate it&#8217;s also important to<br \/>\n02:37<br \/>\ntalk about where you put your cutoff for<br \/>\n02:38<br \/>\nscreening tests for example here in the<br \/>\n02:41<br \/>\nunaffected population they seem to<br \/>\n02:43<br \/>\nmostly cluster around one in the<br \/>\n02:46<br \/>\naffected population clusters around<br \/>\n02:48<br \/>\neight using a cut-off of four what you<br \/>\n02:53<br \/>\nwould find is that there is a 100%<br \/>\n02:55<br \/>\ndetection rate with a zero false<br \/>\n02:58<br \/>\npositive rate this is largely because<br \/>\n02:59<br \/>\nthese two groups do not overlap when<br \/>\n03:02<br \/>\ngroups do overlap such as these two<br \/>\n03:04<br \/>\ngroups with one group clustered around<br \/>\n03:06<br \/>\none and one group clustered around five<br \/>\n03:08<br \/>\nwhere you place your cutoff for your<br \/>\n03:10<br \/>\nscreening test will drive your detection<br \/>\n03:13<br \/>\nrate as well as your false positive rate<br \/>\n03:15<br \/>\nwhat you can see here with the cutoff of<br \/>\n03:17<br \/>\nfour is that the detection rate is 80%<br \/>\n03:20<br \/>\nand the false positive rate is 0%<br \/>\n03:23<br \/>\nbecause really were way above the curve<br \/>\n03:25<br \/>\nof the unaffected population however<br \/>\n03:28<br \/>\nwe&#8217;re not picking up 20% of the<br \/>\n03:30<br \/>\npopulation that is affected using a<br \/>\n03:34<br \/>\ncut-off of two what you see here is that<br \/>\n03:37<br \/>\nthere is a 100% detection rate because<br \/>\n03:40<br \/>\nthe affected curve is completely above<br \/>\n03:42<br \/>\nthe cutoff of two but there is also now<br \/>\n03:45<br \/>\na false positive rate of 15% changing<br \/>\n03:49<br \/>\nthe cutoff to three is probably the most<br \/>\n03:51<br \/>\nideal for this situation here the<br \/>\n03:54<br \/>\ndetection rate is 95% while at the same<br \/>\n03:57<br \/>\ntime the false positive rate is 2% this<br \/>\n04:00<br \/>\nwould be the best cutoff for a screening<br \/>\n04:02<br \/>\ntest in these two populations now let&#8217;s<br \/>\n04:06<br \/>\nuse neural tube defects and<br \/>\n04:07<br \/>\nalpha-fetoprotein to apply some of these<br \/>\n04:09<br \/>\nprinciples of screening and then we will<br \/>\n04:11<br \/>\nmove on to screening test done in early<br \/>\n04:13<br \/>\npregnancy neural tube defects are the<br \/>\n04:15<br \/>\nsecond most frequent major congenital<br \/>\n04:17<br \/>\nanomaly in pregnancy forty five percent<br \/>\n04:19<br \/>\nof these will be in encephalo where<br \/>\n04:22<br \/>\nthere&#8217;s a lot of the top portion of the<br \/>\n04:24<br \/>\nbrain as can be seen the bottom-left<br \/>\n04:26<br \/>\npictures the other forty five<br \/>\n04:28<br \/>\nas spina bifida where there&#8217;s a weakness<br \/>\n04:30<br \/>\nin the spine and the final 10% is a<br \/>\n04:32<br \/>\ncondition called encephalocele<br \/>\n04:34<br \/>\nas you can see in the picture of the<br \/>\n04:36<br \/>\nbaby with the large opening in the back<br \/>\n04:38<br \/>\nof its head the overall incidence of<br \/>\n04:41<br \/>\nopen neural tube defects in the u.s.<br \/>\n04:42<br \/>\npopulation is approximately 1 to 2 per<br \/>\n04:44<br \/>\n1,000 births a previously affected child<br \/>\n04:47<br \/>\nincreases the risk more than tenfold<br \/>\n04:49<br \/>\nhowever 90% of open neural tube defects<br \/>\n04:51<br \/>\nhave no known risk factor and this means<br \/>\n04:53<br \/>\nthat there is a need for screening for<br \/>\n04:55<br \/>\nthe lowest population looking at the<br \/>\n04:58<br \/>\nincidence based on risk factors again<br \/>\n05:00<br \/>\nthe general population has an incidence<br \/>\n05:01<br \/>\nof 1.5 per 1,000 births for a diabetic<br \/>\n05:04<br \/>\nmother it&#8217;s 20 per 1,000 births valproic<br \/>\n05:07<br \/>\nacid use is 10 per 1,000 births one<br \/>\n05:10<br \/>\nprior sip lling with an open roll tube<br \/>\n05:12<br \/>\ndefect gives an incidence of 15 to 30<br \/>\n05:14<br \/>\nper 1,000 births to prior siblings with<br \/>\n05:17<br \/>\noprah neural tube defect gives an<br \/>\n05:18<br \/>\nincidence of 57 per 1,000 births and<br \/>\n05:20<br \/>\nhaving a parent with an open neural tube<br \/>\n05:22<br \/>\ndefect does increase your risk to 11 per<br \/>\n05:25<br \/>\n1000 births alpha-fetoprotein is a<br \/>\n05:28<br \/>\nprotein produced by the fetal liver<br \/>\n05:30<br \/>\nfetal levels peak at about 12 weeks<br \/>\n05:32<br \/>\ngestational age this then moves into the<br \/>\n05:34<br \/>\namniotic fluid and the amniotic fluid<br \/>\n05:36<br \/>\nlevels peak at about 15 weeks and the<br \/>\n05:38<br \/>\nmaternal serum levels rise steadily<br \/>\n05:40<br \/>\nuntil about 32 weeks there is a linear<br \/>\n05:42<br \/>\nrise from 15 to 20 weeks and this is<br \/>\n05:45<br \/>\nhelpful in terms of screening here&#8217;s a<br \/>\n05:47<br \/>\npicture of the rise and<br \/>\n05:49<br \/>\nalpha-fetoprotein from 15 to 20 weeks<br \/>\n05:52<br \/>\nlooking at the distribution of maternal<br \/>\n05:54<br \/>\nserum alpha-fetoprotein the unaffected<br \/>\n05:57<br \/>\npopulation does over lie patients with<br \/>\n05:59<br \/>\nopen spina bifida and those within and<br \/>\n06:02<br \/>\nseparately but what you can see is that<br \/>\n06:04<br \/>\nwith spina bifida and anencephaly the<br \/>\n06:06<br \/>\naverage and the distribution of AFP<br \/>\n06:09<br \/>\nlevels are higher and higher focus on<br \/>\n06:11<br \/>\nthis picture on the maternal serum AFP<br \/>\n06:13<br \/>\nlevel cutoff of 2.5 multiples of the<br \/>\n06:16<br \/>\nmedian and how this is at the far right<br \/>\n06:19<br \/>\nend of the unaffected and begins to<br \/>\n06:21<br \/>\nenter into the areas of open spina<br \/>\n06:23<br \/>\nbifida and anencephaly so you can see<br \/>\n06:26<br \/>\nthat open neural tube defects can be<br \/>\n06:28<br \/>\nscreened with maternal serum<br \/>\n06:29<br \/>\nalpha-fetoprotein and using a 2.5<br \/>\n06:32<br \/>\nmultiples of the median cutoff ninety<br \/>\n06:35<br \/>\npercent of an assembly will be detected<br \/>\n06:36<br \/>\neighty percent of spina bifida will be<br \/>\n06:38<br \/>\ndetected and there is only a three<br \/>\n06:41<br \/>\npercent false<br \/>\n06:41<br \/>\npositive rate elevated maternal serum<br \/>\n06:44<br \/>\nAFP can also be seen with these defects<br \/>\n06:47<br \/>\nhere this includes ventral wall defects<br \/>\n06:49<br \/>\ntriploid e aneuploidy amniotic band<br \/>\n06:52<br \/>\nsequence de pentalogy of Cantrell renal<br \/>\n06:54<br \/>\nagenesis multiple gestation x&#8217;<br \/>\n06:56<br \/>\ncongenital necrosis sacrococcygeal<br \/>\n06:59<br \/>\nteratoma dermatological conditions in<br \/>\n07:02<br \/>\nCory ng ona ultrasound can also be used<br \/>\n07:05<br \/>\nin the screening of spina bifida using<br \/>\n07:08<br \/>\nan ultrasound to detect open neural tube<br \/>\n07:10<br \/>\ndefects it&#8217;s important to first<br \/>\n07:11<br \/>\nrecognize what normal parts of the fetus<br \/>\n07:13<br \/>\nlook like this image shows normal<br \/>\n07:15<br \/>\ncervical and thoracic spine views with<br \/>\n07:17<br \/>\nthe small white dots that are continuous<br \/>\n07:19<br \/>\nlike a train track below<br \/>\n07:20<br \/>\nthis image shows normal lumbar and<br \/>\n07:22<br \/>\nsacral spine use in this picture this is<br \/>\n07:26<br \/>\na normal closed vertebral body and in<br \/>\n07:29<br \/>\nthis image you see normal cranial views<br \/>\n07:31<br \/>\nof the fetal head moving on to what<br \/>\n07:34<br \/>\nyou&#8217;ll see with spina bifida the orange<br \/>\n07:36<br \/>\narrow is pointing to an opening in the<br \/>\n07:38<br \/>\nfetal spine this is a spine in the<br \/>\n07:39<br \/>\nlongitudinal view here as well you can<br \/>\n07:42<br \/>\nsee a splaying of the fetal spine with<br \/>\n07:45<br \/>\nspina bifida as this is an open oral<br \/>\n07:46<br \/>\ntube defect in this view looking at the<br \/>\n07:49<br \/>\nspinal processes as identified by the<br \/>\n07:51<br \/>\nred arrow you can see that it is open<br \/>\n07:53<br \/>\nand the orange arrow is pointing to the<br \/>\n07:55<br \/>\nmeningocele<br \/>\n07:56<br \/>\nthat is protruding from the back of the<br \/>\n07:58<br \/>\nbaby in this transverse view you can<br \/>\n08:01<br \/>\nagain see the meningocele protruding<br \/>\n08:03<br \/>\nfrom the back of the baby right where<br \/>\n08:05<br \/>\nthe orange arrow is pointing when a<br \/>\n08:07<br \/>\nspina bifida is president there&#8217;s also<br \/>\n08:09<br \/>\nchanges in the fetal cranium<br \/>\n08:10<br \/>\nhere you see eleven sign with a red<br \/>\n08:12<br \/>\narrow as indentations in one part of the<br \/>\n08:15<br \/>\ncranium the orange arrow points to an<br \/>\n08:17<br \/>\nenlarged lateral ventricle moving on to<br \/>\n08:21<br \/>\ndiscuss chromosomal abnormalities<br \/>\n08:23<br \/>\nthere are several chromosomal<br \/>\n08:24<br \/>\nabnormalities that can be detected with<br \/>\n08:26<br \/>\nearly pregnancy screening these include<br \/>\n08:28<br \/>\nthe aneuploidies such as trisomy 21 18<br \/>\n08:31<br \/>\nand 13 as well as sex chromosome<br \/>\n08:33<br \/>\nabnormalities such as 45 X or Turner<br \/>\n08:36<br \/>\nsyndrome also triploid II which is a<br \/>\n08:38<br \/>\ncomplete triple copy of the chromosomal<br \/>\n08:40<br \/>\nset these can be translocations as well<br \/>\n08:42<br \/>\nas deletions duplications and inversions<br \/>\n08:44<br \/>\ntrisomy 21 is known as Down syndrome<br \/>\n08:47<br \/>\nthis occurs in approximately one out of<br \/>\n08:48<br \/>\na thousand births the typical phenotype<br \/>\n08:50<br \/>\nis short stature classic facies<br \/>\n08:53<br \/>\ndevelopmental delay and mental<br \/>\n08:54<br \/>\nretardation the<br \/>\n08:55<br \/>\nassociated anomalies such as cardiac<br \/>\n08:57<br \/>\ndefects Doisneau stenosis or atresia and<br \/>\n09:00<br \/>\nshort limbs the average life expectancy<br \/>\n09:01<br \/>\nis 50 to 60 years of age trust me 18 is<br \/>\n09:05<br \/>\nknown as Edwards syndrome this occurs in<br \/>\n09:07<br \/>\none out of five thousand live births<br \/>\n09:09<br \/>\nthe typical phenotype includes short<br \/>\n09:11<br \/>\nstature clenched fists overlapping<br \/>\n09:13<br \/>\ndigits and rocker-bottom feet The<br \/>\n09:15<br \/>\nAssociated physical anomalies include<br \/>\n09:17<br \/>\ntetralogy of flow omphalocele congenital<br \/>\n09:19<br \/>\ndiaphragmatic hernia neural tube defects<br \/>\n09:22<br \/>\nand choroid plexus cysts only five to 25<br \/>\n09:24<br \/>\npercent of patients with trisomy 18 live<br \/>\n09:27<br \/>\npast two years of life last is trisomy<br \/>\n09:30<br \/>\n13 also known as potato syndrome this<br \/>\n09:32<br \/>\noccurs in one out of 10,000 to 20,000<br \/>\n09:35<br \/>\nlive births and there are many<br \/>\n09:37<br \/>\nassociated anomalies including hole<br \/>\n09:38<br \/>\napproximately cleft lip and palate<br \/>\n09:40<br \/>\ncystic hygroma single nostril or absent<br \/>\n09:42<br \/>\nnose<br \/>\n09:43<br \/>\num fallacy on cardiac anomalies<br \/>\n09:45<br \/>\nincluding hypoplastic left heart<br \/>\n09:46<br \/>\nclubfoot or club hand polydactyly and<br \/>\n09:49<br \/>\noverlapping fingers 85% of these<br \/>\n09:51<br \/>\npatients will not live past the first<br \/>\n09:53<br \/>\nyear of life in terms of the various<br \/>\n09:56<br \/>\npregnancy screening options it&#8217;s<br \/>\n09:57<br \/>\nimportant to keep in mind that the<br \/>\n09:59<br \/>\ndiagnostic interventions are chorionic<br \/>\n10:01<br \/>\nvillus sampling and amniocentesis these<br \/>\n10:03<br \/>\nrequire a small needle to be placed in<br \/>\n10:05<br \/>\nthe pregnancy which can disrupt the<br \/>\n10:07<br \/>\npregnancy and cause miscarriage or<br \/>\n10:08<br \/>\npregnancy loss<br \/>\n10:09<br \/>\nthis occurs in 23 out of 1,000<br \/>\n10:11<br \/>\npregnancies that undergo CVS and 7 and<br \/>\n10:14<br \/>\n1,000 pregnancies that undergo<br \/>\n10:16<br \/>\namniocentesis the screening options<br \/>\n10:18<br \/>\ninclude age based screening and then<br \/>\n10:20<br \/>\nmoving on to the more modern screening<br \/>\n10:22<br \/>\ntests of second trimester analytes which<br \/>\n10:24<br \/>\nour hormones and proteins made by the<br \/>\n10:26<br \/>\npregnancy first trimester analytes both<br \/>\n10:29<br \/>\nof these have some incorporation of<br \/>\n10:30<br \/>\nultrasound and finally the newest<br \/>\n10:32<br \/>\ntechnology is cell free field DNA in<br \/>\n10:36<br \/>\nterms of age based screening prior to<br \/>\n10:38<br \/>\nthe advent of ultrasound and serum<br \/>\n10:40<br \/>\nanalytes physicians would screen women<br \/>\n10:42<br \/>\nbased on maternal age to select women at<br \/>\n10:44<br \/>\nhighest risk for amniocentesis the age<br \/>\n10:46<br \/>\ncutoff was somewhere between 35 to 37<br \/>\n10:49<br \/>\nyears old and this was when the risk of<br \/>\n10:51<br \/>\nmiscarriage after amniocentesis<br \/>\n10:53<br \/>\napproximated the risk of Down syndrome<br \/>\n10:55<br \/>\nbased on the woman&#8217;s age for this reason<br \/>\n10:58<br \/>\nadvanced maternal age was set at 35<br \/>\n11:00<br \/>\nyears old age based screening generally<br \/>\n11:02<br \/>\nidentified 30% of cases with Down<br \/>\n11:04<br \/>\nsyndrome by offering amniocentesis to<br \/>\n11:06<br \/>\nthe oldest 5% of the population<br \/>\n11:09<br \/>\nwhat we&#8217;ve seen is that the age of the<br \/>\n11:10<br \/>\npregnant population is increasing and<br \/>\n11:12<br \/>\nthere are more and more women having<br \/>\n11:13<br \/>\npregnancies later in life with the<br \/>\n11:16<br \/>\navailability of the alpha-fetoprotein<br \/>\n11:18<br \/>\ntests identified early on as a marker<br \/>\n11:20<br \/>\nfor open neural tube defects in 1984<br \/>\n11:23<br \/>\narmored cats at all found that there was<br \/>\n11:25<br \/>\nan association of aneuploidy with low<br \/>\n11:27<br \/>\nvalues of maternal serum alpha-theta<br \/>\n11:29<br \/>\nprotein his group and another group went<br \/>\n11:32<br \/>\nback and looked at banks stored serum<br \/>\n11:34<br \/>\nand linked these with Down syndrome and<br \/>\n11:36<br \/>\nanalyzed them and what was found was<br \/>\n11:38<br \/>\nthat between 14 to 22 weeks that the<br \/>\n11:41<br \/>\nmedian AFP was approximately 25 percent<br \/>\n11:43<br \/>\nlower in pregnancies associated with<br \/>\n11:45<br \/>\nDown syndrome after that time new second<br \/>\n11:49<br \/>\ntrimester hormones and proteins were<br \/>\n11:51<br \/>\nfound which were also markers for<br \/>\n11:53<br \/>\naneuploidy the triple screen includes<br \/>\n11:54<br \/>\nalpha-fetoprotein made by the fetal<br \/>\n11:57<br \/>\nliver estriol made by the placenta and<br \/>\n11:59<br \/>\nthe fetus in beta HCG made by the<br \/>\n12:01<br \/>\nplacenta these three values have an<br \/>\n12:03<br \/>\noverall 70 percent sensitivity with a<br \/>\n12:05<br \/>\nfive percent false positive rate and a<br \/>\n12:07<br \/>\nthirty five year old woman to detect<br \/>\n12:09<br \/>\nDown syndrome the quadruple screen<br \/>\n12:11<br \/>\nincludes alpha-fetoprotein made by the<br \/>\n12:13<br \/>\nfetal liver estrella made by the fetus<br \/>\n12:15<br \/>\nand the placenta beta HCG made by the<br \/>\n12:17<br \/>\nplacenta and inhibin a made by the<br \/>\n12:19<br \/>\nplacenta as well as the ovary these four<br \/>\n12:21<br \/>\nvalues have an overall 81 percent<br \/>\n12:23<br \/>\nsensitivity with a five percent false<br \/>\n12:25<br \/>\npositive rate for a woman who is 35<br \/>\n12:27<br \/>\nyears old to detect Down syndrome what<br \/>\n12:30<br \/>\nwas found over time also was that moving<br \/>\n12:32<br \/>\nfrom age based screening to the triple<br \/>\n12:34<br \/>\nscreen and onto the quad screen overall<br \/>\n12:36<br \/>\ndecreased the annual synthesis rate<br \/>\n12:38<br \/>\nlooking at the number of amniocentesis<br \/>\n12:39<br \/>\nneeded to be performed to diagnose one<br \/>\n12:42<br \/>\nDown syndrome case using age required<br \/>\n12:44<br \/>\n125 the triple screened 54 and the quad<br \/>\n12:47<br \/>\nscreen 43 this overall resulted in less<br \/>\n12:50<br \/>\npregnancy losses with 2500 happening<br \/>\n12:53<br \/>\nusing age based screening 1500 with the<br \/>\n12:55<br \/>\ntriple screen and 1300 with the quad<br \/>\n12:57<br \/>\nscreen there is an increase in<br \/>\n12:59<br \/>\nsensitivity with a decrease in the false<br \/>\n13:01<br \/>\npositive rate looking specifically at<br \/>\n13:03<br \/>\nquad screen values at 16 weeks for<br \/>\n13:05<br \/>\npregnancies with trisomy 21 there is low<br \/>\n13:07<br \/>\nalpha-fetoprotein low estriol and<br \/>\n13:09<br \/>\nelevated levels of HCG and inhibit which<br \/>\n13:12<br \/>\ntries to me 18 there are low values for<br \/>\n13:14<br \/>\nall of the four analytes in the quad<br \/>\n13:16<br \/>\nscreen trisomy 13 really particularly<br \/>\n13:18<br \/>\ndepends on the abnormalities that are<br \/>\n13:20<br \/>\npresent in the fetus and as men<br \/>\n13:22<br \/>\nearly on with okra no treat defects<br \/>\n13:24<br \/>\nthere&#8217;s an increase in alpha-fetoprotein<br \/>\n13:27<br \/>\nincorporating ultrasound into the serum<br \/>\n13:29<br \/>\nanalytes also adds to knowledge about<br \/>\n13:31<br \/>\nthe pregnancy it is known that with a<br \/>\n13:33<br \/>\ngenetic sonogram there are phenotypic<br \/>\n13:35<br \/>\nfeatures of the fetus that can be used<br \/>\n13:37<br \/>\nto adjust the likelihood ratios based on<br \/>\n13:39<br \/>\nthe serum screening alone especially for<br \/>\n13:41<br \/>\nDown syndrome this really needs to be<br \/>\n13:43<br \/>\nbased on population and this can be used<br \/>\n13:45<br \/>\nover all really just to reduce the risk<br \/>\n13:47<br \/>\nof aneuploidies if none of these<br \/>\n13:49<br \/>\nfeatures are present the main features<br \/>\n13:52<br \/>\nthat are looked at are as follows nuchal<br \/>\n13:54<br \/>\nthickening Harper called bowel short<br \/>\n13:56<br \/>\nhumorous short femur and echogenic focus<br \/>\n13:58<br \/>\nand pile ethicists before looking at how<br \/>\n14:01<br \/>\nthese change the likelihood ratio let&#8217;s<br \/>\n14:03<br \/>\nsee what some of these look like on<br \/>\n14:04<br \/>\nultrasound in this picture you can see a<br \/>\n14:07<br \/>\nthickening of the back of the baby&#8217;s<br \/>\n14:09<br \/>\nneck called nuchal fold thickening that<br \/>\n14:11<br \/>\nis where the arrow and the ultrasound<br \/>\n14:13<br \/>\npicture and the two arrows on the back<br \/>\n14:15<br \/>\nof the fetuses head and the picture<br \/>\n14:18<br \/>\nMicha genic bowel is whitening of the<br \/>\n14:21<br \/>\nfetal bowel and this can be seen as the<br \/>\n14:23<br \/>\nwhite in the area of the arrow which is<br \/>\n14:25<br \/>\nalso in the area of the fetal abdomen<br \/>\n14:28<br \/>\nthe humerus and femur are long bones<br \/>\n14:31<br \/>\nwhich pretty much show up as straight<br \/>\n14:33<br \/>\nwhite lines on ultrasound what you can<br \/>\n14:34<br \/>\nsee in this ultrasound picture is that<br \/>\n14:36<br \/>\nthe average gestational age of this<br \/>\n14:38<br \/>\nfetus is supposed to be 23 weeks in one<br \/>\n14:40<br \/>\nday and this femur is measuring 20 weeks<br \/>\n14:42<br \/>\nin two days an inch our cardiac academic<br \/>\n14:46<br \/>\nfocus as a small white dot that is<br \/>\n14:48<br \/>\npresent in the fetal heart as can be<br \/>\n14:50<br \/>\nseen by the arrow in this picture<br \/>\n14:52<br \/>\nand pie electus is is an increase of<br \/>\n14:55<br \/>\nfluid seen in the kidney as can be seen<br \/>\n14:57<br \/>\nby this small black circle with the two<br \/>\n15:00<br \/>\narrows pointing to it these ultrasound<br \/>\n15:03<br \/>\nfindings can change the likelihood ratio<br \/>\n15:04<br \/>\nfor isolated markers of Down syndrome<br \/>\n15:06<br \/>\nthe likelihood ratio is most increased<br \/>\n15:09<br \/>\nby seeing an increase in nuchal<br \/>\n15:11<br \/>\nthickness hyper acog bowel also<br \/>\n15:13<br \/>\nincreases the likelihood of Down<br \/>\n15:15<br \/>\nsyndrome also a short humerus is more<br \/>\n15:18<br \/>\nlikely than a short femur and echogenic<br \/>\n15:20<br \/>\nfocus and pilot assists are not nearly<br \/>\n15:22<br \/>\nas strongly associated as the other<br \/>\n15:24<br \/>\nfindings this eventually led to what is<br \/>\n15:27<br \/>\nknown as the first trimester combined<br \/>\n15:29<br \/>\nscreen the nuchal translucency thickness<br \/>\n15:31<br \/>\nis able to measure in the first<br \/>\n15:33<br \/>\ntrimester this picture right here shows<br \/>\n15:35<br \/>\nan increased nickel<br \/>\n15:36<br \/>\nthickness in a first trimester fetus<br \/>\n15:38<br \/>\nwhen combined with pregnancy associated<br \/>\n15:40<br \/>\nplasma protein a and free beta HCG this<br \/>\n15:44<br \/>\nis known as the combined first trimester<br \/>\n15:46<br \/>\nscreen and is very helpful and reliable<br \/>\n15:49<br \/>\nsimilar to the second trimester<br \/>\n15:50<br \/>\nscreening looking specifically at the<br \/>\n15:53<br \/>\nnuchal thickness the more thick the new<br \/>\n15:55<br \/>\nCol thickness becomes the more likely<br \/>\n15:57<br \/>\nthis is associated with aneuploidy at 2<br \/>\n15:59<br \/>\nmillimeters or less the risk of<br \/>\n16:01<br \/>\naneuploidy whether it&#8217;s trisomy 21 18 or<br \/>\n16:03<br \/>\n13 is approximately 1% as the nuchal<br \/>\n16:06<br \/>\nthickness increases to 3 millimeters<br \/>\n16:07<br \/>\nthis overall aneuploidy risk increases<br \/>\n16:10<br \/>\nto 17% and greater than 3 millimeters<br \/>\n16:12<br \/>\nnuchal thickness is associated with a<br \/>\n16:14<br \/>\n67% risk of aneuploidy there are many<br \/>\n16:18<br \/>\nadvantages of first trimester or serum<br \/>\n16:20<br \/>\nscreening these include early detection<br \/>\n16:21<br \/>\na similar sensitivity in false positive<br \/>\n16:24<br \/>\nrate to second trimester screening these<br \/>\n16:26<br \/>\ncan be followed up with an early<br \/>\n16:27<br \/>\ndiagnostic test and allowed the family<br \/>\n16:29<br \/>\nto make decisions about pregnancy<br \/>\n16:30<br \/>\ntermination which is safer when done in<br \/>\n16:33<br \/>\nthe first trimester the disadvantages<br \/>\n16:35<br \/>\ninclude that the first trimester serum<br \/>\n16:37<br \/>\nscreen may over detect cases destined to<br \/>\n16:40<br \/>\nspontaneously abort also it does not<br \/>\n16:41<br \/>\nscreen for open neural tube defects and<br \/>\n16:43<br \/>\nthe diagnostic tests which at this point<br \/>\n16:46<br \/>\nwould be chorionic villus sampling<br \/>\n16:47<br \/>\ncompared to me\u00f6 synthesis has more risk<br \/>\n16:49<br \/>\nalso there&#8217;s a very small testing window<br \/>\n16:51<br \/>\nand the first trimester serum screening<br \/>\n16:53<br \/>\nneeds to be performed at 11 to 13 weeks<br \/>\n16:57<br \/>\nfinally I&#8217;d like to mention briefly cell<br \/>\n17:00<br \/>\nfree fetal DNA it has been known for a<br \/>\n17:02<br \/>\nlong time that fetal cells and field DNA<br \/>\n17:04<br \/>\nend up in the maternal circulation it is<br \/>\n17:06<br \/>\npossible to obtain this genetic material<br \/>\n17:08<br \/>\nthrough a simple maternal blood draw<br \/>\n17:09<br \/>\namplification of small amounts of the<br \/>\n17:11<br \/>\nfetal DNA from the maternal circulation<br \/>\n17:13<br \/>\ncan be performed using massive parallel<br \/>\n17:16<br \/>\nsequencing what ends up happening is<br \/>\n17:17<br \/>\nthat these tests evaluate the relative<br \/>\n17:19<br \/>\nratio of fetal chromosome DNA for<br \/>\n17:22<br \/>\ntrisomy 21 13 and 18 and compare those<br \/>\n17:25<br \/>\nto the maternal DNA present for those<br \/>\n17:27<br \/>\nchromosomes these tests end up being 98<br \/>\n17:29<br \/>\nto 99 percent accurate was no rest the<br \/>\n17:31<br \/>\nfetus the advantages of cell-free fetal<br \/>\n17:35<br \/>\nDNA include detection as early as eight<br \/>\n17:38<br \/>\nto ten weeks a sensitivity greater than<br \/>\n17:40<br \/>\n98% and a false positive rate of<br \/>\n17:42<br \/>\napproximately 0.2% it is minimally<br \/>\n17:44<br \/>\ninvasive and is not dependent on<br \/>\n17:45<br \/>\nultrasound the disadvantages is that up<br \/>\n17:47<br \/>\nuntil recently this could not be used<br \/>\n17:49<br \/>\nfor twins but the<br \/>\n17:50<br \/>\nis changing it is not useful in the<br \/>\n17:52<br \/>\nsetting of placental mosaicism which is<br \/>\n17:54<br \/>\nextremely rare cell-free fetal DNA only<br \/>\n17:56<br \/>\nscreens for common employees and for<br \/>\n17:59<br \/>\ncertain women if there&#8217;s a low fetal<br \/>\n18:01<br \/>\nfraction this cannot be performed and<br \/>\n18:04<br \/>\napproximately 2 to 6% of pregnancies and<br \/>\n18:06<br \/>\nthis is particularly true for the obese<br \/>\n18:08<br \/>\nmother well that&#8217;s about it everybody I<br \/>\n18:10<br \/>\nthink that we&#8217;re able to review some of<br \/>\n18:12<br \/>\nthe foundational principles related to<br \/>\n18:13<br \/>\nscreening tests discuss the more common<br \/>\n18:15<br \/>\nand employees on neural tube defects<br \/>\n18:16<br \/>\nthat can be identified through early<br \/>\n18:18<br \/>\npregnancy screening we introduced serum<br \/>\n18:19<br \/>\nand ultrasound screening through the use<br \/>\n18:21<br \/>\nof alpha-fetoprotein to detect over<br \/>\n18:23<br \/>\nneural tube defects we understood the<br \/>\n18:24<br \/>\nstrengths and limitations of first and<br \/>\n18:26<br \/>\nsecond trimester serum and ultrasound<br \/>\n18:27<br \/>\nscreening and finally we described the<br \/>\n18:29<br \/>\ncell-free fetal DNA and its role in<br \/>\n18:31<br \/>\npregnancy screening thanks so much for<br \/>\n18:33<br \/>\nwatching the video we hope you find it<br \/>\n18:34<br \/>\nhelpful good luck with everything and<br \/>\n18:36<br \/>\nwe&#8217;ll see you in class<br \/>\n18:36<br \/>\ntake care<br \/>\n18:37<br \/>\n[Music]<br \/>\n18:42<br \/>\nyou<\/p>\n<p><\/div>\n<hr \/>\n<p><iframe loading=\"lazy\" src=\"https:\/\/www.youtube.com\/embed\/6zbFCXFtFbU\" width=\"560\" height=\"315\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>Duration 17:57<\/p>\n<input type='hidden' bg_collapse_expand='69e9b554611674034420604' value='69e9b554611674034420604'><input type='hidden' id='bg-show-more-text-69e9b554611674034420604' value='Show Transcript'><input type='hidden' id='bg-show-less-text-69e9b554611674034420604' value='Hide Transcript'><button id='bg-showmore-action-69e9b554611674034420604' class='bg-showmore-plg-button bg-blue-button  '   style=\" color:#fcf7f7;\">Show Transcript<\/button><div id='bg-showmore-hidden-69e9b554611674034420604' ><\/p>\n<p>all right we now move to chapter three<br \/>\n00:08<br \/>\nobstetric all procedures and the first<br \/>\n00:11<br \/>\none that we will talk about is obstetric<br \/>\n00:14<br \/>\nultrasound obstetrical ultrasound has<br \/>\n00:16<br \/>\ntotally revolutionized pregnancy care<br \/>\n00:19<br \/>\nwhen I started my residency in the 1970s<br \/>\n00:25<br \/>\nit was just beginning and the changes<br \/>\n00:28<br \/>\nthat we&#8217;ve seen in obstetric ultrasound<br \/>\n00:31<br \/>\nare just amazing I don&#8217;t think it is<br \/>\n00:34<br \/>\npossible for a patient to get through<br \/>\n00:37<br \/>\npregnancy in the United States with<br \/>\n00:39<br \/>\nregular prenatal care without getting at<br \/>\n00:42<br \/>\nleast one ultrasound ultrasound is an<br \/>\n00:45<br \/>\nimaging modality with low energy high<br \/>\n00:49<br \/>\nfrequency sound waves it has probably<br \/>\n00:52<br \/>\nbeen studied more than any other imaging<br \/>\n00:55<br \/>\nmethod to see if there are any<br \/>\n00:58<br \/>\nabnormalities and effects on the fetus<br \/>\n01:00<br \/>\nand at the low energy high frequency<br \/>\n01:03<br \/>\nwaves that we use today no one has shown<br \/>\n01:06<br \/>\nany adverse effects on the embryo and<br \/>\n01:09<br \/>\nfetus but it always could be that we<br \/>\n01:12<br \/>\nhaven&#8217;t looked long enough yet so we<br \/>\n01:14<br \/>\nalways need to be concerned with that<br \/>\n01:15<br \/>\nthe early ultrasounds were trans<br \/>\n01:18<br \/>\nabdominal trans abdominal can be used<br \/>\n01:22<br \/>\nany time during the pregnancy but the<br \/>\n01:24<br \/>\nimage quality may not be as good it<br \/>\n01:28<br \/>\ndepends on the body mass index of the<br \/>\n01:30<br \/>\npatient it depends on the presence of<br \/>\n01:34<br \/>\nscars in the skin the trans abdominal is<br \/>\n01:38<br \/>\nnot very helpful if you have a three or<br \/>\n01:40<br \/>\nfour hundred pound patient the benefit<br \/>\n01:42<br \/>\nof a transvaginal is it can be used in<br \/>\n01:46<br \/>\nany patient whether she&#8217;s a hundred<br \/>\n01:48<br \/>\npounds or whether she is four hundred<br \/>\n01:49<br \/>\npounds because you get the transducer in<br \/>\n01:53<br \/>\nthe vagina close to the pelvic organs<br \/>\n01:55<br \/>\nyou have very high resolution images the<br \/>\n02:00<br \/>\ndating accuracy of a first trimester<br \/>\n02:01<br \/>\nultrasound is plus or minus five days<br \/>\n02:05<br \/>\nwhich is pretty good<br \/>\n02:07<br \/>\nthe Doppler ultrasound we can use to<br \/>\n02:11<br \/>\nassess blood flow and as we will talk<br \/>\n02:13<br \/>\nabout<br \/>\n02:14<br \/>\nwith fetal antepartum testing we can<br \/>\n02:17<br \/>\nlook at umbilical artery blood flow and<br \/>\n02:20<br \/>\nlook at diastolic and systolic flow and<br \/>\n02:22<br \/>\nwhen we&#8217;re assessing for fetal anemia<br \/>\n02:25<br \/>\nwith a low immunization we can do<br \/>\n02:28<br \/>\nfetal middle cerebral artery blood flow<br \/>\n02:30<br \/>\nand we look at the peak systolic<br \/>\n02:32<br \/>\nmeasurements in those situations this is<br \/>\n02:36<br \/>\na wonderful image it is 12 weeks and 3<br \/>\n02:40<br \/>\ndays and it shows the fetus in a<br \/>\n02:42<br \/>\nsagittal plane you can see that the<br \/>\n02:45<br \/>\nskull is intact you can see that there<br \/>\n02:48<br \/>\nis normal-appearing spine<br \/>\n02:50<br \/>\nthere is no spina bifida you can see the<br \/>\n02:53<br \/>\nabdominal wall is intact<br \/>\n02:55<br \/>\nthere&#8217;s no omphalocele or gastroschisis<br \/>\n02:58<br \/>\nwe can see the mandible the maxilla we<br \/>\n03:01<br \/>\ncan see the nasal bone this is a<br \/>\n03:05<br \/>\nbeautiful appearing normal first<br \/>\n03:08<br \/>\ntrimester ultrasound and the accuracy in<br \/>\n03:10<br \/>\nterms of dating is plus or minus five<br \/>\n03:13<br \/>\ndays the indications for obstetric<br \/>\n03:16<br \/>\nultrasound are many in fact you could<br \/>\n03:19<br \/>\nalmost say that there is an indication<br \/>\n03:22<br \/>\nfor every pregnancy in terms of ectopic<br \/>\n03:25<br \/>\npregnancy to identify is it in the<br \/>\n03:28<br \/>\nuterus that&#8217;s something we talked about<br \/>\n03:30<br \/>\nviability to see is there cardiac motion<br \/>\n03:33<br \/>\nwe talked about that when we&#8217;re looking<br \/>\n03:36<br \/>\nat first an early pregnancy bleeding<br \/>\n03:38<br \/>\ngestational age dating is very important<br \/>\n03:42<br \/>\nand the earlier in pregnancy the<br \/>\n03:44<br \/>\nultrasound dating is performed the more<br \/>\n03:47<br \/>\naccurate is if there are subsequent<br \/>\n03:50<br \/>\nultrasounds we do not change the due<br \/>\n03:53<br \/>\ndate we just look to see is there<br \/>\n03:55<br \/>\nappropriate or inappropriate growth<br \/>\n03:58<br \/>\nmultiple gestation twins and triplets<br \/>\n04:01<br \/>\nand quadruplets the only way to<br \/>\n04:03<br \/>\ndefinitively diagnose that is by<br \/>\n04:05<br \/>\nobstetrical ultrasound amniotic fluid<br \/>\n04:08<br \/>\nvolume is part of our modified<br \/>\n04:11<br \/>\nbiophysical profile which we&#8217;ll talk<br \/>\n04:13<br \/>\nabout later on if the uterus is smaller<br \/>\n04:15<br \/>\nthan dates all ago Hydra Menace may be a<br \/>\n04:19<br \/>\ncause for that we can assess serial<br \/>\n04:21<br \/>\nmeasurements for fetal growth that&#8217;s<br \/>\n04:23<br \/>\ngoing to be important in patients who<br \/>\n04:25<br \/>\nhave chronic hypertension<br \/>\n04:27<br \/>\nwe have diabetes they may be the fetuses<br \/>\n04:30<br \/>\nis too small or the fetus isn&#8217;t growing<br \/>\n04:32<br \/>\nadequately we can evaluate fetal<br \/>\n04:35<br \/>\nwell-being with ultrasound specifically<br \/>\n04:37<br \/>\nwith a biophysical profile where we look<br \/>\n04:40<br \/>\nat gross body movements we look at<br \/>\n04:42<br \/>\nextension and flexion of extremities we<br \/>\n04:44<br \/>\nlook at breathing movements the<br \/>\n04:46<br \/>\nassessment of fetal anomalies is going<br \/>\n04:48<br \/>\nto be important as we do the genetic<br \/>\n04:50<br \/>\nsonogram to identify is there a placenta<br \/>\n04:53<br \/>\nprevia where there is pregnancy bleeding<br \/>\n04:56<br \/>\nand as I talked about just a minute or<br \/>\n04:58<br \/>\nso ago with fetal anemia we can look at<br \/>\n05:01<br \/>\nthe middle cerebral artery peak systolic<br \/>\n05:04<br \/>\nvelocity to see if there&#8217;s evidence of<br \/>\n05:06<br \/>\nfetal anemia we&#8217;ll talk more about that<br \/>\n05:08<br \/>\nunder a low immunization the genetic<br \/>\n05:11<br \/>\nultrasound is a procedure which is no<br \/>\n05:15<br \/>\ndifferent than any other ultrasound but<br \/>\n05:17<br \/>\nit is performed specifically to identify<br \/>\n05:20<br \/>\nif there are any abnormalities<br \/>\n05:21<br \/>\nspecifically anatomic markers of fetal<br \/>\n05:24<br \/>\naneuploidy the ideal time to do the<br \/>\n05:27<br \/>\ngenetic ultrasound is 18 to 20 weeks now<br \/>\n05:30<br \/>\nlet me just say that this is not a<br \/>\n05:32<br \/>\ndiagnosis of aneuploidy but what it will<br \/>\n05:35<br \/>\ndo is to change the risk of aneuploidy<br \/>\n05:39<br \/>\nbecause if you have a normal genetic<br \/>\n05:42<br \/>\nultrasound it cuts your predicted risk<br \/>\n05:45<br \/>\nof fetal aneuploidy by half in other<br \/>\n05:48<br \/>\nwords if the likelihood of a given<br \/>\n05:51<br \/>\nwoman&#8217;s age let&#8217;s say at age 35<br \/>\n05:54<br \/>\nyou have likelihood of Down syndrome of<br \/>\n05:56<br \/>\none in 300 with a normal ultrasound it<br \/>\n06:00<br \/>\nwould be 1 in 600 so the generic things<br \/>\n06:03<br \/>\nthat we look for or any structural<br \/>\n06:05<br \/>\nabnormalities is there any evidence of<br \/>\n06:07<br \/>\nany kind of syndromes and there are<br \/>\n06:09<br \/>\nhundreds if not thousands of syndromes<br \/>\n06:11<br \/>\nbut the specific areas that we will look<br \/>\n06:14<br \/>\nfor which are called genetic markers for<br \/>\n06:17<br \/>\naneuploidy would be neutral skin fall<br \/>\n06:19<br \/>\nthickness which would be at the junction<br \/>\n06:22<br \/>\nof the neck and the thorax in the head<br \/>\n06:24<br \/>\nthe shortened long bone specifically the<br \/>\n06:27<br \/>\nhumerus and the femur PI Alexis&#8217;s is<br \/>\n06:30<br \/>\nwhere we have enlargement of the renal<br \/>\n06:32<br \/>\npelvis<br \/>\n06:33<br \/>\nechogenic intracardiac focus you can see<br \/>\n06:36<br \/>\nwhen you look at the heart that there is<br \/>\n06:39<br \/>\nechogenic<br \/>\n06:39<br \/>\nareas<br \/>\n06:40<br \/>\nwhich are very clear and the densities<br \/>\n06:44<br \/>\nshould be equal to that of bone and then<br \/>\n06:46<br \/>\nis hyper echoic bowel which is also<br \/>\n06:49<br \/>\nassociated with it so these are the five<br \/>\n06:51<br \/>\nareas that we look for with the nuclear<br \/>\n06:53<br \/>\nskinfold being the one that is the<br \/>\n06:55<br \/>\nstrongest predictor the nuclear<br \/>\n06:57<br \/>\ntransitions or NT measurements is a<br \/>\n07:01<br \/>\nfairly recent screening test which is<br \/>\n07:04<br \/>\nperformed in the first trimester which<br \/>\n07:07<br \/>\nis between 10 and 14 weeks and it<br \/>\n07:10<br \/>\nmeasures the fetal fluid collection<br \/>\n07:12<br \/>\nbehind the neck a thickened and T<br \/>\n07:15<br \/>\nmeasurement increases the likelihood of<br \/>\n07:18<br \/>\naneuploidy and cardiac disease we<br \/>\n07:21<br \/>\ncombine the NT measurement with two<br \/>\n07:24<br \/>\nmaternal blood tests which is free beta<br \/>\n07:27<br \/>\nHCG and pap A which is pregnancy<br \/>\n07:31<br \/>\nassociated plasma protein a and by<br \/>\n07:34<br \/>\nlooking at the levels of these two blood<br \/>\n07:36<br \/>\ntests along with the NT screening we can<br \/>\n07:39<br \/>\ncome up with a number giving sensitivity<br \/>\n07:41<br \/>\nand specificity for aneuploidy screening<br \/>\n07:44<br \/>\nso the second trimester screening is a<br \/>\n07:47<br \/>\nquadruple marker screen which has four<br \/>\n07:49<br \/>\nblood tests the first trimester<br \/>\n07:51<br \/>\nscreening has two blood tests and the NT<br \/>\n07:55<br \/>\nor nuchal translucency measurement this<br \/>\n07:59<br \/>\nultrasound image shows very well the NT<br \/>\n08:03<br \/>\nthe nuchal translucency and you can see<br \/>\n08:05<br \/>\ndown in the lower middle part of the<br \/>\n08:08<br \/>\nimage the NT measures 2.1 millimeters<br \/>\n08:14<br \/>\nyou can also see that they have marked<br \/>\n08:18<br \/>\nthe NB the nasal bone and they&#8217;re also<br \/>\n08:23<br \/>\nlooking at the angle between the nasal<br \/>\n08:25<br \/>\nbone and the head you can also see the<br \/>\n08:27<br \/>\nmandible and maxilla these findings can<br \/>\n08:31<br \/>\nbe very helpful in identifying normality<br \/>\n08:34<br \/>\nand they&#8217;re very reassuring if things<br \/>\n08:36<br \/>\nlook like they should chorionic villus<br \/>\n08:40<br \/>\nsampling is an outpatient office<br \/>\n08:43<br \/>\nprocedure performed under ultrasound<br \/>\n08:46<br \/>\nguidance without anesthesia it can be<br \/>\n08:50<br \/>\ndone either tran cervical e or done<br \/>\n08:53<br \/>\ntransferred<br \/>\n08:54<br \/>\na catheter is placed into the precursor<br \/>\n08:59<br \/>\nfor the placenta which is the chorionic<br \/>\n09:02<br \/>\nvillus it does not enter the amniotic<br \/>\n09:06<br \/>\ncavity it does not go into where the<br \/>\n09:09<br \/>\nfetus is but it takes part of the<br \/>\n09:12<br \/>\nplacental tissue a sample is sent to the<br \/>\n09:15<br \/>\nlaboratory for karyotyping because this<br \/>\n09:19<br \/>\nis an invasive procedure there is a low<br \/>\n09:23<br \/>\nbut real pregnancy loss rate which we<br \/>\n09:26<br \/>\nquote at 0.7% the basis of the chorionic<br \/>\n09:30<br \/>\nvillus sampling or CBS is that the<br \/>\n09:33<br \/>\norigin of the placenta and the origin of<br \/>\n09:37<br \/>\nthe fetus were both the same namely the<br \/>\n09:41<br \/>\nzygote<br \/>\n09:42<br \/>\nso whatever the chromosomes of the<br \/>\n09:44<br \/>\nzygote were should be the chromosomes of<br \/>\n09:48<br \/>\nthe fetus and should be the chromosomes<br \/>\n09:50<br \/>\nalso of the placenta so if we identify<br \/>\n09:54<br \/>\nnormal placental chromosome it is highly<br \/>\n09:59<br \/>\nlikely that the fiel karyotype is normal<br \/>\n10:02<br \/>\nas well there is a very low rate of<br \/>\n10:07<br \/>\nplacental mosaicism in other words the<br \/>\n10:09<br \/>\nplacenta may be abnormal but the fetal<br \/>\n10:12<br \/>\nchromosomes are normal that&#8217;s about one<br \/>\n10:15<br \/>\nin a thousand so this is chorionic<br \/>\n10:17<br \/>\nvillus sampling and this is a first<br \/>\n10:19<br \/>\ntrimester procedure with the CBS you do<br \/>\n10:23<br \/>\nnot have any assessment of neural tube<br \/>\n10:27<br \/>\ndefects when you do an amniocentesis and<br \/>\n10:29<br \/>\nyou take amniotic fluid you can do<br \/>\n10:31<br \/>\namniotic fluid AFP so the CBS patients<br \/>\n10:35<br \/>\nare going to have to have the second<br \/>\n10:38<br \/>\ntrimester blood test drawn to assess for<br \/>\n10:41<br \/>\nneural tube defects probably the most<br \/>\n10:44<br \/>\ncommon invasive obstetric or procedure<br \/>\n10:48<br \/>\nis amniocentesis this is an outpatient<br \/>\n10:51<br \/>\nprocedure which is performed after 15<br \/>\n10:54<br \/>\nweeks the reason it isn&#8217;t performed<br \/>\n10:56<br \/>\nbetween 15 weeks is because there isn&#8217;t<br \/>\n10:58<br \/>\nenough amniotic fluid and if you<br \/>\n11:00<br \/>\naspirate the fluid you can have an<br \/>\n11:02<br \/>\nincreased pregnancy loss a needle is<br \/>\n11:05<br \/>\nplaced into a pocket of amniotic<br \/>\n11:07<br \/>\nfluid under direct ultrasound guidance<br \/>\n11:10<br \/>\nso you&#8217;re actually watching as the<br \/>\n11:12<br \/>\nneedle goes through the abdominal wall<br \/>\n11:14<br \/>\nthrough into the amniotic sac and then<br \/>\n11:17<br \/>\nyou aspirate amniotic fluid the amniotic<br \/>\n11:20<br \/>\nfluid contains these living fetal cells<br \/>\n11:24<br \/>\nwhich are shed off from the fetal skin<br \/>\n11:26<br \/>\nwhich are called amnio sites and fetal<br \/>\n11:29<br \/>\nkaryotyping can be performed on the<br \/>\n11:31<br \/>\namnio sites you can also do the amniotic<br \/>\n11:34<br \/>\nfluid AFP more definitive test the<br \/>\n11:37<br \/>\nmaternal serum AFP is not as specific<br \/>\n11:41<br \/>\nand as sensitive as is the amniotic<br \/>\n11:43<br \/>\nfluid AFP so we will do that in addition<br \/>\n11:46<br \/>\nmost commonly if we have the very<br \/>\n11:48<br \/>\nprecious amniotic fluid we&#8217;ll probably<br \/>\n11:50<br \/>\ndo a chromosomes even if the main<br \/>\n11:53<br \/>\npurpose is to look for in neural tube<br \/>\n11:55<br \/>\ndefect the pregnancy last rate is about<br \/>\n11:58<br \/>\none in 200 which is about the same as a<br \/>\n12:02<br \/>\nlikelihood of finding aneuploidy at age<br \/>\n12:04<br \/>\n35 this is an artist conception of an<br \/>\n12:09<br \/>\namniocentesis and you can see the blue<br \/>\n12:12<br \/>\nultrasound transducer which is being<br \/>\n12:15<br \/>\nheld on the abdomen by the<br \/>\n12:17<br \/>\nultrasonographer you can see that there<br \/>\n12:20<br \/>\nis a placenta which is in the fundus of<br \/>\n12:22<br \/>\nthe uterus this fetus is in cephalic<br \/>\n12:25<br \/>\npresentation with the head down and the<br \/>\n12:28<br \/>\nneedle is placed directly under<br \/>\n12:30<br \/>\nultrasound guidance into the amniotic<br \/>\n12:32<br \/>\nsac and you can see the aspiration of<br \/>\n12:34<br \/>\nthe amniotic fluid with the amnio sites<br \/>\n12:39<br \/>\nwithin it pregnancy loss rate is about<br \/>\n12:42<br \/>\nhalf a percent<br \/>\n12:44<br \/>\npercutaneous umbilical blood sampling or<br \/>\n12:47<br \/>\npubb&#8217;s is another invasive procedure a<br \/>\n12:51<br \/>\nneedle is placed trans abdominally goes<br \/>\n12:54<br \/>\ninto the umbilical vein and we aspirate<br \/>\n12:58<br \/>\nfetal blood this is done under direct<br \/>\n13:02<br \/>\nultrasound guidance after 20 weeks<br \/>\n13:04<br \/>\ngestation and the reason it isn&#8217;t done<br \/>\n13:06<br \/>\nbefore 20 weeks gestation is because the<br \/>\n13:09<br \/>\numbilical vein is so small so tiny is<br \/>\n13:12<br \/>\ndifficult to get a needle in and when<br \/>\n13:15<br \/>\nyou try to do pubb&#8217;s very early it has a<br \/>\n13:18<br \/>\nsignificant pregnancy loss rate<br \/>\n13:21<br \/>\nthis is done trance abdominal II it can<br \/>\n13:23<br \/>\nbe diagnostic it can be therapeutic in<br \/>\n13:26<br \/>\nterms of diagnosis we can assess blood<br \/>\n13:29<br \/>\ngases of the fetus we can assess carrier<br \/>\n13:33<br \/>\ntyping of the fetus we can assess IgG<br \/>\n13:36<br \/>\nIgM antibodies you can do electrolytes<br \/>\n13:40<br \/>\non the blood in terms of therapy we can<br \/>\n13:44<br \/>\ndo any treatment transfusion if we have<br \/>\n13:46<br \/>\nfetal anemia which we will talk about<br \/>\n13:49<br \/>\nlater on under a low immunization when<br \/>\n13:52<br \/>\nyou go in through the uterine wall you<br \/>\n13:55<br \/>\ncan irritate the uterus you could have<br \/>\n13:57<br \/>\npreterm contractions you you have to go<br \/>\n14:00<br \/>\nthrough the membrane so you could<br \/>\n14:02<br \/>\npotentially rupture the membranes<br \/>\n14:04<br \/>\npregnancy loss rate is not high but it<br \/>\n14:07<br \/>\nis higher than amniocentesis it is one<br \/>\n14:09<br \/>\nto two percent pregnancy loss rate the<br \/>\n14:13<br \/>\nlast procedure that we will talk about<br \/>\n14:15<br \/>\nis fetus copy this is performed with a<br \/>\n14:18<br \/>\nfiber-optic scope it is done in the<br \/>\n14:21<br \/>\noperating room after 20 weeks gestation<br \/>\n14:25<br \/>\nunder general anesthesia typically this<br \/>\n14:30<br \/>\nscope is going to be larger than a<br \/>\n14:32<br \/>\nneedle and so the likelihood of<br \/>\n14:35<br \/>\nrupturing membranes is higher the<br \/>\n14:37<br \/>\nlikelihood of preterm labor is higher<br \/>\n14:40<br \/>\nthe pregnancy loss rate is 2 to 5<br \/>\n14:42<br \/>\npercent clearly the loss rate will be a<br \/>\n14:46<br \/>\nfunction of the experience of the<br \/>\n14:50<br \/>\noperator the more of these you&#8217;ve done<br \/>\n14:52<br \/>\nthe less problems you&#8217;ll have<br \/>\n14:54<br \/>\nindications for this would be<br \/>\n14:56<br \/>\nintrauterine surgery and what is done<br \/>\n14:58<br \/>\nmore and more lately is to do laser<br \/>\n15:02<br \/>\nvaporization of placental vessels which<br \/>\n15:05<br \/>\nare joining to fetuses with twin twin<br \/>\n15:09<br \/>\ntransfusion syndrome and if you don&#8217;t do<br \/>\n15:12<br \/>\na laser ablation before the pregnancy<br \/>\n15:16<br \/>\ngoes much further you can get either<br \/>\n15:18<br \/>\nloss of both twins or one twin up to 80%<br \/>\n15:20<br \/>\nof the time so this is going to be<br \/>\n15:22<br \/>\nimportant<br \/>\n15:22<br \/>\nthere are rare situations in which you<br \/>\n15:24<br \/>\nneed to do a fetal skin biopsy and this<br \/>\n15:27<br \/>\nwould be another indication for fetus<br \/>\n15:28<br \/>\ncopy the risks bleeding infection<br \/>\n15:31<br \/>\nrupture of membranes and fetal loss this<br \/>\n15:34<br \/>\nis the highest<br \/>\n15:35<br \/>\npregnancy loss rate of any of the<br \/>\n15:37<br \/>\nprocedures this is a artist&#8217;s conception<br \/>\n15:41<br \/>\nof a fetus cope which is placed into the<br \/>\n15:45<br \/>\nuterus and you can see we have two<br \/>\n15:47<br \/>\nfetuses one which is stuck on the bottom<br \/>\n15:51<br \/>\nof the uterus with Allah goyim Nia&#8217;s the<br \/>\n15:53<br \/>\nother one which is floating in<br \/>\n15:55<br \/>\npolyhydramnios this is a twin twin<br \/>\n15:57<br \/>\ntransfusion syndrome and the fetus cope<br \/>\n16:01<br \/>\nis being used to laser the connection<br \/>\n16:04<br \/>\nbetween the twin<br \/>\n16:05<br \/>\nokay let&#8217;s summarize what we have just<br \/>\n16:08<br \/>\nsaid this is on prenatal diagnostic<br \/>\n16:10<br \/>\ntesting in your notes a chorionic villus<br \/>\n16:14<br \/>\nsampling is done between 10 to 12 weeks<br \/>\n16:16<br \/>\nof gestation with a pregnancy loss rate<br \/>\n16:19<br \/>\nof 0.7 percent and we aspirate placental<br \/>\n16:22<br \/>\nprecursors the first trimester screening<br \/>\n16:25<br \/>\nis done between 10 and 14 weeks zero<br \/>\n16:28<br \/>\npregnancy loss rate because none of<br \/>\n16:29<br \/>\nthese are invasive procedures and this<br \/>\n16:31<br \/>\ninvolves the nuchal translucency and two<br \/>\n16:34<br \/>\nblood tests the pregnancy associated<br \/>\n16:35<br \/>\nplasma protein a and free beta HCG the<br \/>\n16:39<br \/>\namniocentesis is the most common<br \/>\n16:41<br \/>\ninvasive procedure is done at fifteen<br \/>\n16:43<br \/>\nweeks or more a 0.5 pregnancy loss rate<br \/>\n16:46<br \/>\nand we aspirate from the amniotic fluid<br \/>\n16:49<br \/>\namniotes and amniotic fluid AFP we could<br \/>\n16:53<br \/>\nalso do chromosome the expanded AFP you<br \/>\n16:57<br \/>\ncan see is expanded with the X the X is<br \/>\n16:59<br \/>\na shorthand for expanded AFP is now the<br \/>\n17:02<br \/>\nquadruple marker screen it is done<br \/>\n17:05<br \/>\nbetween 15 to 20 weeks go talk about<br \/>\n17:07<br \/>\nthat coming up zero pregnancy loss rate<br \/>\n17:09<br \/>\nbecause it&#8217;s non-invasive and the four<br \/>\n17:12<br \/>\ntests that we do are maternal serum AFP<br \/>\n17:15<br \/>\nbeta HCG estriol<br \/>\n17:16<br \/>\nand inhibin a the sonogram is probably<br \/>\n17:19<br \/>\nthe most common prenatal diagnostic<br \/>\n17:22<br \/>\nprocedure done between 18 to 20 weeks<br \/>\n17:24<br \/>\nzero pregnancy loss rate it is<br \/>\n17:26<br \/>\nnon-invasive and this involves a genetic<br \/>\n17:28<br \/>\nsonogram the fetus copy is done between<br \/>\n17:30<br \/>\n18 to 20 weeks with the 3 to 5 percent<br \/>\n17:33<br \/>\npregnancy loss rate this can be lasering<br \/>\n17:36<br \/>\nthe blood vessels in twin twin<br \/>\n17:38<br \/>\ntransfusion syndrome and fetal biopsy<br \/>\n17:41<br \/>\nthe percutaneous umbilical blood sample<br \/>\n17:43<br \/>\nor pubs is done at 20 or more weeks<br \/>\n17:46<br \/>\ngestation<br \/>\n17:47<br \/>\nwe have a 1 to 2% pregnancy loss rate<br \/>\n17:49<br \/>\nand we aspirate blood from the umbilical<br \/>\n17:52<br \/>\nvein because that&#8217;s the largest vessel<br \/>\n17:55<br \/>\nand that&#8217;s the end of chapter 3<\/p>\n<p><\/div>\n<hr \/>\n","protected":false},"excerpt":{"rendered":"<p>\ufeff Duration 9:32 Duration 18:47 Duration 17:57<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":160,"menu_order":13,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-376","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/pages\/376","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/comments?post=376"}],"version-history":[{"count":0,"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/pages\/376\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/pages\/160"}],"wp:attachment":[{"href":"https:\/\/brooksidepress.org\/pa_obgyn\/wp-json\/wp\/v2\/media?parent=376"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}