A cesarean section, or c-section, is a surgical procedure in which incisionsare made through a woman's abdomen and uterus to deliver her baby. The procedure is performed in the United States on nearly one of every four babies delivered--more than 900,000 babies each year. C-sections are performed wheneverabnormal conditions complicate labor and vaginal delivery, threatening the life or health of the mother or the baby.
The most common reason that a cesarean section is performed (in 35% of all cases, according to the U.S. Public Health Service) is that the woman has had aprevious c-section. The "once a cesarean, always a cesarean" rule originatedback when the incision in the uterus was made vertically; the resulting scarwas weak and had a risk of rupturing during later deliveries. Today, the incision is almost always made horizontally across the lower end of the uterus (this is called a "low transverse incision"), resulting in reduced blood lossand a decreased chance of rupture. This kind of incision allows many women tohave a vaginal birth after a cesarean (VBAC).
The second most common reason that a c-section is performed (in 30% of all cases) is difficult childbirth due to nonprogressive labor (dystocia). Uterinecontractions may be weak or irregular, the cervix may not be dilating, or themother's pelvic structure may not allow adequate passage for birth.
Another 12% of c-sections are performed to deliver a baby in a breech presentation: buttocks or feet first. Breech presentation is found in about 3% of all births. When a c-section is being considered because the baby is in a breech position, the doctor may first attempt to reposition the baby. The doctor may also try a vaginal breech delivery, depending on the size of the mother'spelvis, the size of the baby, and the type of breech position the baby is in.
In 9% of all cases, c-sections are performed in response to fetal distress. Fetal distress refers to any situation that threatens the baby's oxygen supply, such as the umbilical cord getting wrapped around the baby's neck. This mayappear on the fetal heart monitor as an abnormal heart rate or rhythm.
The remaining 14% of c-sections are indicated by other serious factors. One is prolapse of the umbilical cord: the cord is pushed into the vagina ahead ofthe baby and becomes compressed, cutting off blood flow to the baby. Anotheris placental abruption: the placenta separates from the uterine wall beforethe baby is born, cutting off blood flow to the baby. The risk of this is especially high in multiple births (twins, triplets, or more). A third factor isplacenta previa: the placenta covers the cervix partially or completely, making vaginal delivery impossible. In some cases requiring c-section, the babyis in a transverse position, lying horizontally across the pelvis, perhaps with a shoulder in the birth canal.
The mother's health may also make delivery by c-section the safer choice, especially in cases of maternal diabetes, hypertension, genital herpes, Rh bloodincompatibility, and preeclampsia (high blood pressure related to pregnancy).
There are several ways that obstetricians and other doctors diagnose conditions that may make a c-section necessary. Ultrasound testing reveals the positions of the baby and the placenta. Fetal heart monitors, in use since the 1970s, transmit any signals of fetal distress. Oxygen deprivation may be determined by testing the pH of a blood sample taken from the baby's scalp, or by checking the amniotic fluid for meconium (feces). A lack of oxygen causes an unborn baby to defecate.
When a c-section becomes necessary, the mother is prepped for surgery. A catheter is inserted into her bladder and an intravenous (IV) line is inserted into her arm. Leads for monitoring the mother's heart rate, heart rhythm, and blood pressure are attached. In the operating room, the mother is given anesthesia--usually a regional anesthetic (epidural or spinal), making her numb from below her breasts to her toes. In some cases, a general anesthetic will beadministered. Surgical drapes are placed over the body, except the head; these drapes block the direct view of the procedure.
The first incision opens the abdomen, and is usually made horizontally acrossand above the pubic bone (informally called a "bikini cut"). The second incision opens the uterus. Once the uterus is opened, the amniotic sac is ruptured and the baby is delivered. The time from the initial incision to birth is typically five minutes.
After the umbilical cord is clamped and cut, the newborn is evaluated. The placenta is removed from the mother, and her uterus and abdomen are stitched, or sutured, closed (surgical staples may be used instead in closing the outermost layer of the abdominal incision). Suturing may take an additional 30-40 minutes.
Following this procedure, a woman commonly experiences gas pains, incision pain, and uterine contractions. A woman who undergoes a c-section requires boththe care given to any new mother and the care given to any patient recovering from major surgery. She should be offered pain medication that does not interfere with breastfeeding. She should be encouraged to get out of bed and walk around 8-24 hours after surgery to stimulate circulation (thus avoiding theformation of blood clots) and bowel movement. She should nap when the baby does, limit climbing stairs to once a day, and avoid lifting anything heavierthan the baby.
Full recovery may be seen in four to six weeks. As the woman heals, she may gradually increase appropriate exercises to regain abdominal tone. She may resume driving after two weeks, although some doctors recommend waiting for sixweeks, the typical recovery period from major surgery.
Because a c-section is a surgical procedure, it carries more risk to both themother and the baby. The mother is at risk for increased bleeding and infection of either incision, the urinary tract, or the tissue lining the uterus (endometritis). Less commonly, she may receive injury to the surrounding organs. When a general anesthesia is used, she may experience complications from the anesthesia. Very rarely, she may blood clots leading to pelvic thrombophlebitis (inflammation of the major vein running from the pelvis into the leg) ora pulmonary embolus (a blood clot lodging in the lung).
Undergoing a c-section may also cause psychological distress beyond hormonalmood swings and postpartum depression ("baby blues"). A woman may feel disappointment and a sense of failure for not experiencing a vaginal delivery. Shemay feel isolated if the father or birthing coach is not with her in the operating room, and may feel helpless from a loss of control over labor and delivery with no opportunity to actively participate. Women who undergo a c-section should be encouraged to share their feelings with others and seek professional help if negative emotions persist. Hospitals can often recommend supportgroups for such mothers.