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Vaginal Birth After Cesarean Birth

Careful review of all prior cesarean delivery operative reports is essential in counseling about the safest delivery method. Women with a prior classical or low vertical incision extending into the contractile portion of the uterus should not be allowed to go through labor. For such patients, fetal lung maturity can be confirmed by amniocentesis at 36 weeks of gestation before repeat cesarean birth vaginal birth after cesarean.

Otherwise, the safety of vaginal birth after cesarean delivery should be emphasized at the first prenatal visit. Vaginal delivery should be strongly encouraged in women who have had one previous transverse incision and should be offered to women with two or more.

Women can be counseled about the success rate of 75% with vaginal birth after cesarean delivery. Although higher rates of successful vaginal birth after cesarean delivery are noted in women who had a primary cesarean delivery indicated by breech presentation (75-91%) and fetal distress (6184%), even women with prior dystocia.

Although a positive attitude is helpful in encouraging a trial of labor, no woman should be forced to attempt vaginal birth after cesarean delivery. Uterine rupture can be catastrophic and may result in serious maternal and neonatal morbidity or death. Uterine scar rupture can be asymptomatic (2%); fortunately, it is usually symptomatic and associated with an abrupt change in the FHR in approximately 70% of cases. Bleeding and abdominal pain occur less than 10% of the time. Serious maternal and fetal morbidity from uterine rupture can be decreased by appropriate intrapartum surveillance with continuous fetal monitoring, early diagnosis.

Neither oxytocin nor epidural anesthesia should be withheld from an appropriate candidate for vaginal birth after cesarean delivery. Some authors advocate vaginal birth after cesarean delivery for twins and macrosomic fetuses, but such research is based on small numbers.

Routine evaluation of the uterine scar was recommended formerly, although there is now general agreement that such evaluation is necessary.

Cesarean and Puerperal Hysterectomy

The willingness to perform elective cesarean hysterectomy has decreased over the past two decades (emergency hysterectomy occurs in fewer than 1% of all cesarean deliveries). Currently, the most common indications for emergent hysterectomy include uterine atony unresponsive to medical management, placenta accreta, uterine rupture, and laceration of major uterine vessels.

Puerperal hysterectomy is associated with increased intraoperative and postoperative maternal morbidity mainly related to genitourinary tract injury, longer operative times, increased blood loss, and higher rates of infection. Common complications include postoperative febrile morbidity (10-50%), blood transfusion (18-30%), cuff hematoma (5-13%), bladder injury (3-10%), abdominal incision infection or dehiscence (3-9%), reoperative laparotomy for bleeding (1-4%), and ureteral injury (0.44-2.5%). During surgery, care should be taken to quickly gain control of the vascular blood supply and to mobilize the bladder to prevent ureteral injury.

Perimortem Cesarean

In cases of cardiac arrest, perimortem cesarean delivery not only increases fetal survival but also aids cardiopul-monary resuscitation efforts. Delivery of the fetus may optimize cardiopulmonary resuscitation, which generates only 30% of the normal output and may be hampered by vena caval compression and the maternal supine position. While continuing cardiopulmonary resuscitation efforts, it is important to rapidly assemble teams responsible for the management of both the mother and infant during this emergent procedure. Perimortem cesarean is performed without concern for a sterile operative field.

Optimally, delivery of a viable fetus should occur within 4-6 minutes of cardiac arrest to reduce the likelihood of fetal or neonatal death or brain injury. Conversely, if cardiopulmonary resuscitation efforts have restored a spontaneous maternal pulse, it is preferable to allow intrauterine resuscitation of the fetus before delivery under sterile conditions (if the indication for cesarean delivery persists). When signs of fetal life are present even outside of this window of optimal timing, perimortem cesarean delivery should be attempted because reports have documented 1015% fetal survival more than 15 minutes after cardiac arrest.

Vaginal Breech Delivery

The rate of cesarean delivery for fetuses with intrapartum breech presentation now exceeds 90%. Of the remaining 10%, some are delivered vaginally before cesarean delivery can be performed. Only a small percentage of patients elect to undergo a trial vaginal breech delivery. Criteria for vaginal breech delivery at term include an adequate maternal pelvis, frank breech presentation without hyper-extension of the fetal head, and an estimated fetal weight between 2.5 and 4.0 kg. The practitioner should be experienced in managing vaginal breech delivery.

There is a critical shortage of patients for both residency training and maintenance of delivery skills in the management of vaginal breech deliveries. Furthermore, there are no prospective randomized trials with sufficient power to demonstrate differences in uncommon adverse neonatal outcomes. A large meta-analysis of breech presentation at term reviewed perinatal outcome in 24 studies according to the intended mode of delivery. The overall neonatal morbidity from trauma was significantly increased in the elective vaginal breech group with an odds ratio of 3.86 (95% confidence interval, 2.22-6.69). The authors concluded that until a large randomized trial can be performed, planned cesarean delivery should be strongly considered for persistent breech.