occiput posterior
Pronunciation: OK-si-put pos-TEER-ee-or
Fetal head position with the back of the head toward the mother's spine, complicating delivery.
Full Definition
Occiput posterior (OP) is a fetal head position where the back of the baby's head (occiput) faces toward the mother's spine rather than toward her front. This position, occurring in 5-10% of deliveries, is also called "sunny-side up" because the baby's face points toward the mother's abdomen. OP position can result in more difficult and prolonged labor due to the larger diameter of the fetal head that must pass through the pelvis. Many OP babies will rotate to the more favorable occiput anterior position during labor, but persistent OP position may require operative vaginal delivery or cesarean section. The condition is associated with increased back pain during labor ("back labor"), longer second stage, and higher rates of episiotomy and perineal trauma.
Usage
Usage note: Distinguish from other malpositions; specify degree if known (e.g., LOP, ROP).
In Context
- "The fetus remained in occiput posterior position despite maternal position changes and prolonged pushing." — Labor progress note
- "Occiput posterior presentation contributed to the patient's severe back pain throughout labor." — Delivery summary