Vaginal Delivery

Delivering the Baby

During labor, uterine contractions result in progressive dilatation and effacement of the cervix. This is called the first stage of labor.

When her cervix reaches complete cervical dilatation, the woman enters the second stage of labor. The second stage lasts until the delivery of the baby.

During delivery, you have three goals. First, you need to complete this delivery with a healthy mother. Second, and it is a close second, you need to complete the delivery with a healthy infant. And third, and it is a close third, you want this to be a happy experience for everyone.

The second stage of labor can be frightening to the mother. She may have the distressing symptoms of significantly more painful contractions, dizziness, breathlessness, nausea, and feelings of being out of control. You can make this life experience much more pleasant by keeping a calm demeanor, a low, relaxed voice, and offering a steady stream of verbal reassurance that the sensations she’s experiencing are normal, that she is doing fine, and the baby is doing fine.

During the second stage of labor, the woman will feel the uncontrollable urge to bear down. This Valsalva or pushing effort has the effect of increasing the expulsive forces and speeding the delivery process. With the onset of a contraction, she takes several, rapid, deep breaths. Then she holds her breath and tightens her stomach muscles, as though she were trying to move her bowels. She pushes for 10 seconds, relaxes, takes another breath, and pushes for another 10 seconds. Most women can get three or four pushes into a single contraction.

Understand that the reason for pushing is to speed the delivery process. It is not necessary to push at all. I’ve had the privilege of delivering two patients who were not capable of pushing. One was periplegic and the other was quadriplegic. They both had normal 1st and 2nd stages of labor. During the second stage, they both had normal descents of their infants and both delivered spontaneously, without forceps or vacuum. In both cases, their uteruses did all the work and did it very effectively.

Occasionally you will find a patient who is completely dilated who does not feel the urge to push. This might be because of a very effective epidural anesthetic, or perhaps she just doesn’t feel like pushing. My advice is to leave her alone and let nature continue its’ safe processes. So long as the fetus is doing well, it really doesn’t matter whether her second stage of labor lasts a short time or a long time. If you encourage her to push when she doesn’t feel like it, you will likely exhaust her with ineffective exercises and wound her self confidence. If the fetus is in jeopardy, then you should consider operative delivery.

For many women, the most effective way to push is in the semi-recumbent position. She will usually push more effectively if her knees are pulled back towards her shoulders.

However:

  • Some women find they are not comfortable in the semi-reclining position and they may push while tilted toward one side or the other.
  • Some women prefer to deliver on their side, with one knee drawn up and the other leg straightened (the Sims position).
  • Some women prefer to deliver in the sitting or squatting position.

All of these positions are just fine and each offers some advantages in comparison to the others. I believe that each patient usually chooses the position in which they are most comfortable, and may change positions if the original position becomes uncomfortable. As a birth attendant, you should be flexible and prepared to deliver the baby no matter what position the woman assumes. That said, most of my patients choose the semi-recumbent position as most comfortable for the delivery. Sometimes, some particular maternal factor or the presence of labor complications dictates the requisite position for delivery.

Duration of the second stage is typically an hour or two for a woman having her first baby. For a woman having a subsequent baby, the second stage is usually shorter, less than an hour. Should the second stage last longer than these limits, I consider that a prolonged second stage of labor, that is associated with increased risks. The patient should be re-evaluated and therapeutic intervention considered, such as oxytocin augmentation, or operative delivery.

During the second stage, try to measure the fetal heart rate every 5 minutes. Sustained fetal tachycardia (greater than 160 BPM) or sustained fetal bradycardia (less than 110 BPM) are considered indications for expedited delivery.

If you are utilizing electronic fetal monitoring, remember that variable decelerations are commonly seen and are not considered threatening unless they are severe (more than 60 second deceleration lasting more than 60 seconds), persist, and are accompanied by fetal tachycardia or bradycardia. In such cases, expedited delivery is usually undertaken.

Delivery is the final part of the second stage of labor. The second stage begins with complete dilatation and ends when the baby is completely out of the mother. The exact time of delivery is normally taken at the moment the baby’s anterior shoulder (the shoulder delivering closest to the mother’s pubic bone) is out.

As the fetal head passes through the birth canal, it normally demonstrates, in sequence, the “cardinal movements of labor.” These include: Engagement, Descent, Flexion, Internal Rotation, Extension, External Rotation, and Expulsion.

  • Engagement is when the fetal head reaches 0 station.
  • Descent means the fetal head descends past 0 station.
  • Flexion means the fetal head is flexed with the chin to its’ chest.
  • With Internal Rotation the fetal head rotates from occiput transverse to occiput anterior.)
  • Extension. The head extends with crowning, passing through the vulva.
  • External Rotation. Once the head has cleared the pubic rami in the occiput anterior position, it returns to its’ occiput transverse orientation, a maneuver called external rotation or sometimes restitution.
  • Expulsion means the shoulders and torso of the baby are delivered.

Delivery of the baby
During the delivery, the fetal head emerges through the vaginal opening, usually facing toward the woman’s rectum. This is the normal position and is called “occiput anterior,” meaning the fetal back of the head, the occiput, is positioned anteriorly, close to the mother’s pubic symphysis.

As the fetal head delivers, support the perineum to reduce the risk of perineal laceration from uncontrolled, rapid delivery. This doesn’t require a lot of force.

There are some delivery complications that would benefit from making an episiotomy or small incision in the vaginal wall to enlarge the vaginal opening prior to delivery. But for most deliveries, making an episiotomy is not necessary, small spontaneous lacerations being easily repaired.

After the fetal head delivers, allow time for the fetal shoulders to rotate and descend through the birth canal. This pause also allows the birth canal to squeeze the fetal chest, forcing amniotic fluid out of the baby’s nose and mouth.

After a reasonable pause (15-30 seconds), have the woman bear down again, delivering the shoulders and torso of the baby.

Clamp and Cut the Umbilical Cord
After the baby is born, leave the umbilical cord alone until the baby is dried, breathing well and starts to pink up. During this time, keep the baby more or less level with the placenta still inside the mother.

Once the baby is breathing, put two clamps on the umbilical cord, about an inch (3 cm) from the baby’s abdomen. Use scissors to cut between the clamps.

During the transition from intrauterine to extrauterine life, the umbilical cord will continue, for a short time, to provide oxygenated blood to the fetus. Once the baby is breathing, then blood is shunted to its lungs where it receives much better oxygenated blood than it was getting from the placenta.

While the cord remains intact, elevation of the fetus above the level of the placenta (for example, resting on the mother’s abdomen) results in some pooling of newborn blood within the placenta and can make the baby somewhat anemic. Holding the baby below the level of the placenta results in pooling of placental blood within the newborn. This isn’t good either, as the rapid homolysis of the fetal hemoglobin can lead to increased problems with neonatal jaundice. It is better to keep the baby more or less level with the placenta until the cord is clamped.

If the baby is not breathing well after delivery and needs resuscitation, immediately clamp and cut the cord so you can move the baby to the resuscitation area.

Delivery the Placenta
After delivery of the baby, the placenta is still attached inside the uterus. Sometime later, the placenta will detach from the uterus and then be expelled. This process is called the “3rd stage of labor” and may take just a few minutes or as long as an hour.

Signs that the placenta is beginning to separate include:

  • A sudden gush of blood
  • Lengthening of the visible portion of the umbilical cord.
  • The uterus, which is usually soft and flat immediately after delivery,  becomes round and firm.
  • The uterus, the top of which is usually about half-way between the pubic bone and the umbilicus, seems to enlarge and approach the umbilicus.

Immediately after the delivery of the baby, uterine contractions stop and labor pains go away. As the placenta separates, the woman will again feel painful uterine cramps. As the placenta descends through the birth canal, she will again feel the urge to bear down and will push out the placenta.

If the placenta is not promptly expelled, or if the patient hemorrhages while awaiting delivery of the placenta, this is called a “retained placenta” and it should be manually removed.

After delivery of the placenta, the uterus normally contracts firmly, closing off the open blood vessels which previously supplied the placenta. Without this contraction, rapid blood loss will likely prove to be very problematic.

To encourage the uterus to firmly contract, oxytocin can be given after delivery either intramuscularly or intravenously. Breast feeding the baby or providing nipple stimulation (rolling the nipple between thumb and forefinger) will cause the mother’s pituitary gland to release oxytocin internally, causing similar, but usually milder effects.

A simple way to encourage firm uterine contraction is with uterine massage. The fundus of the uterus (top portion) is vigorously massaged to keep it the consistency of a tightened thigh muscle. If it is flabby, the patient will likely continue to bleed.

 

Last Modified Feb 26, 2017 @ 3:10 pm

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