Cesarean Delivery Explained
Reason for Procedure
A cesarean delivery is indicated in any situation in which labor and / or vaginal delivery pose significant risks to the mother, the baby, or both. The decision to perform a cesarean depends on the context of the overall situation. In each case, the relative risks to both the mother and fetus associated with cesarean versus vaginal delivery must be taken into consideration. In some cases, the choice is clear; in others, opinions may differ. The leading indications responsible for 85% of cesarean deliveries include prior cesarean delivery, breech presentation, abnormal labor (dystocia), and fetal distress (Joy, “Cesarean Delivery”).
Abnormalities of labor (dystocia) are among the most frequent indications for cesarean birth. They may include abnormal uterine contractions, infection in the maternal pelvis, or problems with the fetus that prolong labor such as a fetal head too large to pass through the mother’s pelvis (cephalopelvic disproportion) or a very large baby (macrosomia). Prolonged labor usually poses greater risks to the fetus than the mother. Dystocia accounts for approximately 12% of deliveries in women who have not had a previous cesarean delivery, and may be responsible for up to 60% of all cesarean deliveries, making it the most significant contributing factor to cesarean delivery in the US (Joy, “Abnormal Labor”).
Fetal indications for cesarean delivery include malpresentation, twin gestations, congenital anomalies, and fetal distress, including fetal heart rate abnormalities that may endanger the life of the fetus during passage through the birth canal and may also indicate congenital heart problems. Electronic fetal monitoring has increased the number of cesarean births by up to 40% (Joy, “Cesarean Delivery”).
An abnormal position of the fetus, such as the baby lying with its buttocks down (breech presentation), sideways (transverse presentation), or with a brow/posterior face position in the uterus, can make vaginal delivery impossible or risky and requires a cesarean section to prevent fetal trauma.
If there are two or more fetuses (multiple gestation), a cesarean section may be performed for the safety of the multiple babies. Congenital abnormalities of the fetus may also require a cesarean to reduce fetal risk or trauma from a vaginal delivery.
A premature infant may have to be delivered by cesarean section due to fetal or maternal complications. With premature rupture of the membranes, unless labor begins spontaneously, the alternatives are to intensify the contractions (induction of labor) or to do a cesarean delivery. In many such cases, cesarean is preferable in order to reduce fetal risk.
Erythroblastosis fetalis can result from a blood type incompatibility (such as Rh incompatibility) between mother and fetus, and cause anemia or hemolysis in the fetus. If the fetus is severely affected or if fetal distress occurs, a cesarean is performed.
In some cases, the umbilical cord drops out through the cervix (prolapses) before the fetus is delivered. This can compress the cord and interrupt the baby’s blood supply, and generally requires an emergency cesarean.
A malpositioned placenta that totally or partially covers the opening of the cervix (placenta previa) is associated with maternal hemorrhage and increased fetal risk. Depending on the degree of cervical blocking, it usually requires a cesarean. Total previa, in which the placenta completely covers the cervix, always requires a cesarean.
Premature separation of the placenta from the uterine wall before delivery (abruptio placentae) can result in loss of fetal blood supply as well as severe maternal hemorrhage. Unless vaginal delivery can be accomplished rapidly, cesarean section is indicated. Small, stable abruptions do not usually require a cesarean.
Certain maternal infections, such as HIV or genital herpes active at the time of labor, can be an indication for a cesarean because passing the fetus through an infected birth canal can result in a life-threatening infection in the newborn.
Pregnancy-induced hypertension (pre-eclampsia or eclampsia, also called toxemia of pregnancy) may endanger both the mother and fetus. The decision to perform a cesarean depends on the severity of the condition and on how soon vaginal delivery can reasonably be accomplished.
Idiopathic thrombocytopenic purpura (ITP), a condition characterized by a reduced platelet count, is an autoimmune disorder in the mother that can also reduce the baby’s platelet count and result in a blood-clotting defect that can cause bleeding. A cesarean may be performed in the presence of ITP because the trauma of a vaginal birth may cause bleeding into the infant’s brain (intracranial hemorrhage). A mild or moderately reduced platelet count (thrombocytopenia) is not unusual in pregnancy but does not typically affect the fetus or require cesarean delivery.
A pregnancy complicated by diabetes mellitus may pose significant fetal risk. In some cases, a cesarean section may be performed to remove the fetus as soon as possible from a dangerous intrauterine environment. With severe diabetes, the circulation in the placenta can be so compromised that intrauterine growth retardation results, and fetal heart distress in labor is common. In less severe diabetes, the high maternal serum glucose leads to very large babies (macrosomia), with increased rates of cephalopelvic disproportion and, thus, cesarean sections.
Advanced invasive cervical cancer may be a reason to avoid labor because dilation of the cervix could promote spread of the cancer. However, localized cervical cancer (carcinoma in situ) is not an indication for cesarean.
Cerebral aneurysm or history of cerebral hemorrhage in the mother can be an indication for cesarean because bearing down during labor puts the mother at risk for a stroke. Serious heart disease such as mitral stenosis is another indication for cesarean in order to reduce the demands of labor and vaginal delivery on a compromised heart.
Sometimes the mother has a condition in which the muscles of the cervix are weak (incompetent cervix), which results in repeated spontaneous abortions (miscarriages). In these circumstances, the cervix is sewn closed in a surgical procedure called cervical cerclage. This allows the pregnancy to continue to term. In cases in which the stitches are left in place permanently, the baby is delivered by cesarean section.
Other indicators for cesarean delivery include a narrow vaginal opening (vaginal atresia), failed medical induction of labor, pelvic tumors, or severe obesity.
A woman who has had a previous cesarean section may require a repeat cesarean, depending on the type of uterine incision previously used, the circumstances of her first cesarean section, and the time elapsed since the previous cesarean section. If the uterine incision was a horizontal (transverse) lower segment incision, it may be safe to proceed with vaginal delivery in a subsequent pregnancy. However, if the woman has a history of more than one low transverse cesarean section, she is at slightly increased risk for uterine rupture. If a previous cesarean incision was a vertical uterine incision (classical or upper segment), subsequent cesarean deliveries will help avoid the risk of the uterus breaking open (rupture). Cesarean is also performed if the previous incision type is unknown or undocumented or if the primary cesarean section was complicated by postpartum infection.
How Procedure is Performed
Cesarean delivery is performed under general or regional (spinal or epidural) anesthesia. Antibiotics are frequently administered preoperatively (prophylaxis), and a tube to drain urine and monitor urinary output (urinary catheter) is inserted into the bladder. A transverse, lower abdominal incision is the most common method used to access the perineal cavity. A slightly curved incision is first made into the lower abdomen, and then the layers (such as the skin and muscle) are opened one at a time. The bladder is dissected free of the lower uterus and then held out of the way with retractors to gain access to the uterus. A low transverse uterine incision is made in 90% of cesareans when the fetal presentation is normal and the lower uterine segment is well developed (Joy, “Cesarean Delivery”). If the fetus is very large, very small, or in an abnormal position, a vertical uterine incision may be necessary to provide a larger opening.
Once the uterus has been opened, the sac holding the fetus (amniotic sac) is ruptured and the fetus is delivered by lifting the fetal head clear of the incision. The time between making the incision and delivering the fetus is critical because of the trauma sustained by the fetal head during the procedure. The umbilical cord is clamped and cut, and blood is sampled from the cord for blood typing; a piece of the cord is held aside to obtain blood gas or other blood results if fetal status is in question. After the fetus is delivered, oxytocin is injected into the intravenous fluid to increase uterine contractions for manual delivery of the placenta; this method may take longer, but less bleeding is expected. The inside of the uterus is checked to ensure that no abnormalities or residual material of pregnancy remains. Any excess blood or amniotic fluid is suctioned out of the uterus and abdominal cavity. Then the uterus and layers of the abdomen are stitched (sutured) together, one layer at a time. The woman is monitored for vital signs, signs of infection, excessive bleeding, or other complications. Urinary output is monitored to ensure proper fluid balance is maintained. Discharge from the hospital usually occurs within 4 days after cesarean delivery.
Most cesarean deliveries are successful and create no complications for the mother or infant.
Maternal morbidity and mortality are higher with cesarean delivery than with vaginal delivery; about 6 to 22 deaths per 100,000 live cesarean births are reported to occur annually, nearly twice that of vaginal delivery (Joy, “Cesarean Delivery”). Most maternal deaths associated with cesarean delivery are attributed in part to the surgical procedure itself and also to the specific condition that necessitated cesarean birth (Joy, “Cesarean Delivery”).
Women who undergo cesarean section may require physical therapy prior to discharge from the hospital. Physical therapists instruct women in incision support, deep-breathing exercises, gentle abdominal strengthening, pelvic floor exercises, and early mobility. Physical therapists instruct women to keep their incision clean and to look for any signs of infection at the incision site, such as increased redness or drainage. To decrease the risk of pulmonary complications after surgery, women perform deep-breathing exercises with the use of an incentive spirometer. Women may need to splint the incision for this activity as well to decrease pain.
Gentle abdominal strengthening exercises and pelvic and Kegel exercises help to increase the strength of the pelvic floor muscles that may have been weakened during pregnancy or injured if a vaginal delivery was attempted prior to cesarean section. Women also are encouraged to walk after a cesarean section to help decrease the risk of clot formation in the legs.
Maternal complications can include fever, infection of the uterus, inflammation of the endometrium (endometritis), infection of the incision, urinary tract infection, bladder or bowel injury, excessive bleeding (hemorrhage), shock secondary to hemorrhage, blockage of an artery to the lung by a blood clot formed at the surgical site (pulmonary embolism), high blood pressure (hypertension), and inflammation of a vein due to clot formation (thrombophlebitis). On occasion, removal of the uterus (hysterectomy) must be performed if there is uncontrolled bleeding, uterine infection, or cancer. With general anesthesia comes the risk of inhalation of stomach contents (aspiration) that can cause inflammation of the lungs (pneumonitis). Fewer than 1 in 1,000 cesarean deliveries result in maternal death (Joy, “Cesarean Delivery”). Death may result from an underlying illness, hemorrhage and related coagulation problems (disseminated intravascular coagulation, or DIC), or complications associated with anesthesia. Depression may develop following childbirth.
Long-term complications may include scar tissue (adhesions) that can cause intestinal blockage (obstruction), incisions that open (dehiscence) postoperatively, and uterine rupture during subsequent labor. The incidence of uterine rupture during vaginal birth after cesarean is as high as 10% with the classical (vertical) type of uterine incision (Joy, “Cesarean Delivery”). Uterine rupture can be life-threatening for both the mother and the fetus.
Fetal complications include an increased incidence of respiratory distress syndrome and incomplete lung expansion (atelectasis).
Ability to Work
Stair climbing, lifting, and driving may be temporarily restricted after cesarean section, usually for less than a week. Accommodations may also include less strenuous or slower-paced work, part-time work, and / or frequent rest periods. Flexible hours, job sharing, and on-site child care are useful for many new mothers. Mothers who are breastfeeding may require additional break time and a private room in which to breastfeed their infant or pump (express) breast milk. The vast majority of women who have uncomplicated pregnancy and cesarean delivery recover to modified work capacity by 6 weeks postpartum.
- Fischer, Richard, and Alexandre Hageboutros. “Thrombocytopenia in Pregnancy.” eMedicine. Eds. Rodger L. Bick, et al. 27 Jun. 2006. Medscape. 15 Sep. 2009
- Fischer, Richard. “Breech Presentation.” eMedicine. Eds. Andrea Witlin, et al. 7 Jul. 2009. Medscape. 15 Sep. 2009.
- Joy, Saju, and Stephen A. Contag. “Cesarean Delivery.” eMedicine. Eds. Jordan G. Pritzker, et al. 2 Apr. 2009. Medscape. 15 Sep. 2009
- Joy, Saju, Patricia L. Scott, and Deborah Lyon. “Abnormal Labor.” eMedicine. Eds. Robert K. Zurawin, et al. 3 Aug. 2009. Medscape. 15 Sep. 2009