The interpretation of cases involving serious neonatal morbidity also appears subjective and speculative. How serious are the 5 cases of brachial plexus injury in the vaginal-delivery group when most were already improving 2 to 4 days after delivery? Further, measures of neonatal morbidity such as the Apgar score are influenced by the subjectivity of unblinded caregivers and rarely signify long-term morbidity. Intracerebral or intraventricular hemorrhage, another measure of neonatal morbidity, also may be unrelated to the mode of delivery,8 whereas measures of serious neonatal morbidity such as spinalcord injury or basal skull fracture actually occurred in the planned-cesarean group.
Even if we accept the alarming rates of serious neonatal morbidity presented in the study—1.4% in the planned-cesarean group versus 3.8% in the planned-vaginaldelivery group—the risk differential, also known as the attributable risk (the difference attributable to a trial of labor) is only 2.4%. For practical purposes, this means that among 100 women with breech presentation, a trial of labor is associated with 2 more undesired outcomes on average than if there were no trial of labor. Applying the same reasoning for the 0.2% difference in prolonged NICU admissions, among 1,000 women with breech presentation, a trial of labor is associated with only 2 more prolonged NICU admissions (longer than 4 days) than if there were no trial of labor.
The middle road: deciding case by case
Martin L. Gimovsky, MD
Professor and Vice Chairman Department of OBG Director, Maternal-Fetal Medicine Newark Beth Israel Medical Center Newark, NJ
While the design of the Term Breech Trial was exceptional and the data it yielded valuable, I do not believe it definitively answered the question of which mode of delivery is best for breech presentations at term—vaginal or cesarean. Rather, I would argue for making that decision on a case-by-case basis.
The importance of imaging.Accurate assessments of fetal weight and size and the maternal pelvis are critical. When these measurements cannot be confirmed by sophisticated imaging, i.e., ultrasound, x-ray pelvimetry, computed tomography (CT), or magnetic resonance imaging (MRI), the outcome of vaginal delivery is highly uncertain. No gravida carrying a breech infant should undergo a trial of labor unless such imaging is available. When it is not, I would opt for elective cesarean.
Maternal versus neonatal morbidity.We tend to assume that the mother should sustain whatever morbidity is necessary—barring severe injury and death, of course—to ensure the delivery of a healthy infant. Thus, we underestimate the significance of the potential adverse effects of cesarean section: greater blood loss, wound infection or dehiscence, systemic infection, and the need for a vertical or greatly extended transverse uterine incision, not to mention the likelihood that the woman will need to undergo cesarean section at future deliveries. While the health of the infant is extremely important, it does not necessarily have to come at the mother’s expense. If a gravida is properly selected, vaginal delivery can protect the health of both mother and child.
The wishes of the patient.While a policy of planned cesarean delivery for term breech infants may be advisable in many cases, it overlooks one vital element: the desires of the mother. I believe those wishes should be weighed along with the potential benefits and risks of cesarean section. Several of my patients agreed to participate in the Term Breech Trial until they were randomized to planned cesarean. Because they so strongly desired vaginal delivery, they withdrew from the trial rather than proceed with cesarean section. Of course, I confirmed fetopelvic adequacy and other factors key to successful vaginal delivery using the most sophisticated means. When vaginal delivery appeared feasible, I acquiesced to their wishes.
For many women, the ability to deliver their infant vaginally is extremely important. These women may see cesarean delivery—even in the case of breech presentation—as a loss of involvement in the birth of their child. When facilities are adequate and the physician is experienced in vaginal breech delivery, I believe the patient should be allowed to proceed with vaginal delivery if she chooses, provided it is not contraindicated by other factors.1
Last thoughts.Cesarean deliveries are breech extractions, with all the attendant risks; one does not bypass the fact of breech presentation by opting for cesarean. An assisted breech delivery can be just as safe—or safer—for both the fetus and mother, provided the patient is properly selected and the physician has the necessary expertise and adequate facilities at his or her disposal. For these reasons, I offer women with breech fetuses at term both options: vaginal and cesarean delivery. The final decision, of course, depends on a number of elements, since the problem of breech presentation is multifactorial.
During my career, I have participated in hundreds of breech deliveries, both by cesarean and vaginally. Although external cephalic version (ECV)—with tocolysis performed either prior to or in early labor—is a satisfactory solution to the malpresentation problem,2 the selective and safe management of breech labor and delivery is an invaluable addition to the tools available to the accoucheur. (For more details on ECV, see “Achieving version in breech presentations:3 approaches” on page 33.)
REFERENCES
1. Gimovsky ML, O’Grady JP, Morris B. Assessment of computed tomographic pelvimetry within a selective breech presentation management protocol. J Reprod Med. 1994;39:489-491.
2. Gimovsky ML. Short-term tocolysis adjunctive to intrapartum term breech management. Am J Obstet Gynecol. 1985;153-233.