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Sometimes the baby is in a position, like breech (buttocks-first) or transverse (cross-wise), that makes a vaginal birth risky. Other times certain medical conditions, such as placenta previa (placenta is attached too low, blocking the baby's exit) or placenta abruptio (placenta is partially or completely detached, threatening the baby's oxygen and nutrient supply), make vaginal birth nearly impossible.
A Cesarean section delivery is performed if a vaginal birth is not safe or possible for the mother or the baby.
Review Date 10/15/2024
Updated by: John D. Jacobson, MD, Professor Emeritus, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
