gynecology and obstetrics
Fetal Presentation, Position, and Lie (Including Breech Presentation)
Key Points
If a fetus is in the occiput posterior position, operative vaginal delivery or cesarean delivery is often required. In breech presentation, the presenting part is a poor dilating wedge, which can cause the head to be trapped during delivery, often compressing the umbilical cord. For breech presentation, usually do cesarean delivery at 39 weeks or during labor, but external cephalic version is sometimes successful before labor, usually at 37 or 38 weeks. 