Predictive factors and short-term fetal outcomes of breech presentation: a case-control study.

OBJECTIVE: This study evaluated the predictive factors and short-term fetal outcomes of breech presentation by comparing breech and cephalic pregnancies of >or=36 weeks gestation.
MATERIALS AND METHODS: Two hundred and one breech and 149 cephalic pregnancies of >or=36 weeks gestation, with no other maternal or fetal problems, were compared with regard to placental localization, fetal heart rate variability, smoking, body mass index, maternal weight gain, placental weight, birth weight, sex, Apgar scores, and umbilical cord length.
RESULTS: Maternal weight gain, body mass index at term, smoking and hemoglobin values were significantly higher in breech presentation than in cephalic pregnancies. The placenta was located in the cornu-fundal region in 63.2% of breech presentations and 26.8% of cephalic presentations (p<0.001). Placental weights were 657 g and 597 g, respectively (p<0.001). Umbilical cord length was shorter in breech than cephalic pregnancies (p<0.001). Although breech pregnancies had significantly reduced fetal heart rate variability (p<0.001), Apgar scores were much higher in breech fetuses than in cephalic fetuses. Ninety-five percent of breech pregnancies underwent cesarean sections.
CONCLUSION: Cornu-fundal localization of the placenta, smoking, greater maternal weight gain, higher body mass index at term, greater placental weight, shorter umbilical cord, and lower estimated fetal weight may be predictive of persistent breech presentation. Reduced fetal heart rate variability did not have an adverse effect on Apgar scores after cesarean delivery in breech fetuses with no other problems at term.