FIGURE 45-26 Internal podalic version. Upward pressure on the head by an abdominal hand is applied as downward traction is exerted on the feet.
Any attempt to deliver twins vaginally in a woman who has previously undergone one or more cesarean deliveries should be carefully considered. Some studies support the safety of attempting a vaginal birth after cesarean delivery (VBAC) for selected women with twins (Cahill, 2005; Ford, 2006; Varner, 2005). According to the American College of Obstetricians and Gynecologists (2017 c), no evidence currently suggests an increased risk of uterine rupture, and women with twins and one previous cesarean delivery with a low transverse incision may be considered candidates for trial of labor. At Parkland Hospital, we recommend repeat cesarean delivery.
Several unusual intraoperative problems can arise during cesarean delivery of twins or higher-order multiples. Supine hypotension is common, and thus gravidas are positioned in a left lateral tilt to delect uterine weight of the aorta (Chap. 4, p. 63). A low transverse hysterotomy is preferable if the incision can be made large enough to allow atraumatic delivery of both fetuses. Piper forceps can be used if the second twin is presenting breech (Fig. 28-11, p. 547). In some cases, a vertical hysterotomy beginning as low as possible in the lower uterine segment may be advantageous. For example, if a fetus is transverse with its back down and the arms are inadvertently delivered irst, it is much easier and safer to extend a vertical uterine incision upward than to extend a transverse incision laterally or to make a "T" incision vertically.
Fetal heart rate monitoring during labor with triplet pregnancies is challenging. A scalp electrode can be attached to the presenting fetus, but it is diicult to ensure that the other two fetuses are each being monitored separately. With vaginal deliv ery, the first neonate is usually born with little or no manipula tion. Subsequent fetuses, however, are delivered according to the presenting part. his often requires complicated obstetri cal maneuvers such as total breech extraction with or without internal podalic version or even cesarean delivery. Associated with malposition of fetuses is an increased incidence of cord prolapse. Moreover, reduced placental perfusion and hemor rhage from separating placentas are more likely during delivery.
For all these reasons, many clinicians believe that preg cesarean delivery (American College of Obstetricians and
Gynecologists, 2016). Vaginal delivery is reserved for those cir cumstances in which survival is not expected because fetuses are delivery hazardous to the mother. Others believe that vaginal delivery is safe under certain circumstances. Grobman and asso delivery completion rates of 88 and 84 percent, respectively, in women carrying triplets who underwent a trial of labor. Neo natal outcomes did not difer from those of a matched group of triplet pregnancies undergoing elective cesarean delivery. Con versely, in one review of more than 7000 triplet pregnancies, vaginal delivery was associated with a higher perinatal mortality rate (Vintzeleos, 2005). Lappen and coworkers (2016) reported similar results from the database of the Consortium on Safe
Labor. They recommended prelabor cesarean delivery for trip lets. Importantly, the overall cesarean delivery rate among trip lets was 95 percent.
In some cases of higher-order multi fetal gestation, reduction of the fetal number to two or three improves survival of the remaining fetuses. Selective reduction implies early pregnancy intervention, whereas selective termination is performed later. he procedure should be performed by an operator skilled and experienced in sonographically guided procedures.