The Facts of Life: Examining Reproductive Health

Childbirth

For several days prior to the onset of true labor, the cervix begins to soften and dilate, sometimes reaching 1-3 centimeters (cm) by the time labor begins. At the onset of labor, the combination of muscular contractions in the uterus and the pressure of the baby in the amniotic sac, causes the cervix to dilate creating a passageway for the baby. These contractions may be irregular; but as labor progresses, they become stronger and more evenly spaced. At full dilation, the cervical opening reaches 10 cm and the woman feels a strong urge to push as the baby descends. With the help of the uterine muscles and the force of maternal pushing, the baby moves into the vaginal canal. The first sign of labor may occur with the beginning of regular uterine contractions or when a woman's "waters" break. This "water" or amniotic fluid, surrounds and cushions the fetus for the nine months it spends in the womb. The membranes most often rupture during the early stages of labor although for 10% of women they rupture prematurely. The pressure of the baby's head against the fluid-filled membranes as it moves down toward the cervix contributes to this rupture. Some physicians encourage women to come to the hospital after the waters break to prevent infection. Many practitioners however, feel the risk of infection is small and advise women to wait until labor is more firmly established.

21.Uterus with fetus from Leonardo da Vinci's Notebook 1510-1512

Prepared Childbirth
Women and their childbirth partners may attend special classes during the pregnancy to prepare them for labor and delivery. Prepared childbirth, as it is called, consists of exercises and techniques of breathing and relaxation that facilitate the birth process. In class, women may try out the various labor positions - for example, reclining on the back or the side, kneeling on hands and knees or squatting.

The Stages of Labor
There are three stages of labor. In the first stage, which is generally the longest, the woman's cervix dilates and thins out and her contractions become more frequent. This process of labor varies greatly in length and intensity and women's experiences at this stage vary widely. A woman may be in labor from only a few hours to as long as two days. By the time she is fully dilated (at 10 cm), the contractions are generally two to three minutes apart. Many women feel that it is helpful and relaxing in early labor to take long walks and baths, cook, go to the movies or otherwise keep themselves active and focused on something other than the cramps caused by contractions.

The second stage involves the movement of the infant from the uterus through the vagina (the birth canal) to the actual birth of the child. This journey may take a few minutes or several hours. As long as the baby's heart rate remains normal, a longer labor will not harm the newborn. The baby's head will be born first, unless the baby is in breech position (feet first). After the head, the shoulders, one at a time, and the body emerge.

22. Concept of fetus and placenta of 12 days circa 1600

The third stage begins after the delivery of the baby and continues until the placenta, or afterbirth, is expelled. When the infant emerges, it is still attached to the placenta by the umbilical cord. The umbilical cord is clamped and cut, and the placenta is usually delivered within 30 minutes. Until the placenta is delivered, the mother is vulnerable to infection and hemorrhage. When delivery is normal, it is reasonable to wait for the placenta to be expelled. However, if the placenta is not expelled on its own, an injection of a drug may be given to increase and strengthen uterine contractions or the placenta may be manually removed.

Cesarean Section
A cesarean section, or c-section, is almost always performed in a hospital, with anesthesia and equipment for blood transfusions at hand. Anesthesia, either regional (spinal or epidural) or general is administered and the woman's abdominal area is scrubbed with an antiseptic solution. The procedure can begin when the abdomen is numb, or the general anesthesia has taken effect and the mother is unconscious.

The physician begins by making an incision low on the abdomen, through the skin, connective and fatty tissue, above the pubic bone. Another incision is then made through the peritoneum, the protective membrane over the abdominal cavity. The tissue overlying the lower uterus is opened next, and the doctor moves the bladder away from the uterus. An incision is then made through the uterine muscle. The amniotic sac is ruptured and the physician eases the baby out, clearing its nose and mouth. Now, the umbilical cord is clamped and cut and the placenta and amniotic sac are removed. Antibiotics may be administered to ward off infection and the woman's uterus and abdominal wall are stitched closed, layer by layer.

In many cases, a cesarean section is necessary to protect the life of the mother and/or child. For example: the woman's cervix may not dilate sufficiently, or at all; the baby's head may be too large for the mother's pelvis; or a breech or otherwise unusual presentation could preclude a vaginal delivery. A c-section may also be necessary in the case of an abnormal fetal heart rate pattern or certain health problems encountered by the mother during pregnancy, such as rapidly increasing blood pressure, or abnormal vaginal bleeding. However, it is thought that many c-sections performed today are unnecessary. In 1968, only 5% of all U.S. births were by c-section; by 1987, the rate was 25%. Today, almost all women who have had prior c-sections are being encouraged to give birth vaginally, if deemed safe by their clinicians.

23. Positions assumed by twins in the womb

Forceps Delivery
Forceps are designed to extract the baby by the head from the birth canal during a difficult delivery. Obstetrical forceps consist of two curved, metal blades that are inserted between the vaginal wall and the infant's head. To ease the baby out, the forcep handles are brought together. Prior to the introduction of obstetrical forceps in the eighteenth century, childbirth was strictly a woman's domain. Although the forceps were designed by Peter Chamberlen in the 1620s, they did not come into general use until 1728. (Until that time, the Chamberlen family carefully guarded the design of the instrument.) With the widespread use of forceps, male practitioners began to assist in delivery, claiming that female practitioners lacked the physical strength to handle the obstetrical forceps. Male physicians attempted to discourage female midwives in their pursuit of an obstetrical career.

Forceps are no longer used as frequently as in the past, however they are sometimes necessary to deliver a baby. A forceps delivery is usually less traumatic to baby and mother than a cesarean section. There are a few risks associated with a forceps delivery. Forceps may leave temporary marks on the baby's head, cause stress to the baby's neck and spine, or damage nerves in the baby's face. They may also cause lacerations or soft tissue damage to the mother.

24. Nursery and service room (1933)
Lying-in Hospital at the University of Chicago