Delivery presentationsPregnancy - delivery presentation; Labor - delivery presentation; Occiput posterior; Occiput anterior; Brow presentation
Delivery presentation describes the way the baby is positioned to come down the birth canal for delivery.
Your baby must pass through your pelvic bones to reach the vaginal opening. The ease at which this passage will take place depends on how your baby is positioned during delivery. The best position for the baby to be in to pass through the pelvis is with the head down and the body facing towards the mother's back. This position is called occiput anterior (OA).
In breech position, the baby's bottom is facing down instead of the head. Your health care provider will most often detect this in an office visit before your labor begins. Most babies will be in the head-down position by about 34 weeks.
Part of your prenatal care after 34 weeks will involve making sure your baby is in the head-down position.
If your baby is breech, it is not safe to deliver vaginally. If your baby is not in a head-down position after your 36th week, your provider can explain your choices and their risks to help you decide what steps to take next.
Lanni SM, Gherman R, Gonik B. Malpresentations. In: Gabbe SG, Niebyl JR, Simpson JL, et al, eds. Obstetrics: Normal and Problem Pregnancies. 7th ed. Philadelphia, PA: Elsevier; 2017:chap 17.
Lew GH, Pulia MS. Emergency childbirth. In: Roberts JR, ed. Roberts and Hedges' Clinical Procedures in Emergency Medicine. 6th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 56.