a. Contractions. Rhythmic, involuntary contractions of the uterus accomplish the process of birth which is called parturition.

These involuntary contractions (also called labor pains) become more intense, last longer, and occur closer together in time until they finally cause the cervix to dilate (to open) to a diameter of 10 cm (4 inches).

As the uterine contractions become stronger, longer, and closer together, abdominal muscles contract, causing the woman to feel like bearing down or pushing. Contractions of two sets of muscles (uterine and abdominal) expel the fetus and the placenta. The woman often feels uterine contractions as high or low back pain.

b. Progress of Contractions. As labor progresses, you can feel the contractions by placing your hand on the mother’s abdomen, just above the umbilicus (the navel).

An early sign of labor is the discharge of a blood-containing mucus called the bloody show. This mucus has accumulated in the cervical canal during pregnancy. Another early sign is the rupture of the amniotic sac, allowing clear fluid to trickle or gush from the woman’s vagina.

c. True Labor. The mother is in true labor if:

(1) Uterine contractions are occurring at regular intervals.

(2) Contractions of the uterus are painful and hard.

(3) Pain is felt in both the front and back of the abdomen.

(4) Dilation and effacement of the cervix is accomplished.

(5) The fetal head is starting to descend.

(6) The fetal head is fixed between contractions.

(7) Bulging or rupture of the membranes of the cervix occurs. (This sign may or may not occur in true labor.)