Vaginal vs. cesarean delivery for preterm breech presentation of singleton infants in California: a population-based study.

OBJECTIVE

To examine the morbidity and mortality associated with vaginal breech delivery (VBD) of premature, low-birth-weight (LBW) (< 2.5 kg) newborns as compared to delivery by cesarean section.

STUDY DESIGN

A retrospective cohort study of singleton, preterm (< 37 weeks), LBW, nonanomalous newborns in California (January 1, 1991-December 31, 1999) was performed. Neonatal morbidity and mortality by route of delivery were compared.

RESULTS

Overall, 14,417 LBW, preterm, breech newborns were delivered (14% vaginally and 86% by cesarean). There were 150,570 LBW, preterm, cephalic newborns, of whom 82% were delivered vaginally. VBD of LBW newborns in nulliparous women was associated with increased neonatal mortality in newborns weighing 500-1,000 g (OR 11.7; 95% CI 7.9, 17.2), 1,001-1,500 g (OR 17.0; 95% CI 6.8, 42.7), 1,501-2,000 g (OR 7.2; 95% CI 2.4, 21.4), and 2,001-2,500 g (OR 6.6; 95% CI 2.1, 21.2) as compared with breech delivery by cesarean in nulliparous women. Birth trauma was increased in VBD of newborns weighing 1,500-2,000 g (OR 3.8; 95% CI 1.4, 10.1) and 2,001-2,500 g (OR 4.5; 95% CI 2.6, 7.9) as compared to breech delivery by cesarean in nulliparous women. Birth asphyxia was increased in breech newborns weighing 2,001-2,500 g (OR 3.5; 95% CI 2.2, 5.6) delivered vaginally in nulliparous women as compared to cephalic vaginal deliveries.

CONCLUSION

VBD of the preterm, LBW newborn is associated with significantly increased neonatal mortality as compared to cesarean section at similar birth weights. Birth trauma (> 1,500 g) was greater with VBD as compared to breech delivery by cesarean, and asphyxia (> 2,000 g) was greater with VBD as compared to cephalic vaginal delivery, suggesting that cesarean delivery may be a safer route of delivery for preterm breech fetuses.