What Are the Different Fetal Positions?

During pregnancy and when preparing for childbirth, there are exercises moms can do when the baby is active to get it in the optimal fetal position, which is known as baby spinning. Starting at the 35th week of pregnancy, talk to your doctor about maternal positioning.

Occiput anterior (OA) or vertex presentation

This is the optimal fetal positioning for childbirth. The baby enters the pelvis with their head down and chin tucked to the chest, facing the mother's back. The head points to the birth canal in this position.

There are two more presentations in OA:

1. Face and brow presentation
   • The baby will remain in the OA position, but the face, rather than the head, will be pointing toward the birth canal.
   • This occurs when the chin is not tucked against the chest and instead points outward.
   • During a vaginal examination, the doctor can detect this position by feeling the baby's bony jaws and mouth.
   • In brow presentation, the baby will be in the OA position with their forehead pointing toward the birth canal. The doctor can feel the anterior fontanelle and the orbits of the forehead during the vaginal examination.
2. Compound presentation
   • One arm lies along with the head, pointing toward the birth canal.
   • The arms may slide back during the delivery process, but if they do not, extra care must be taken to safely remove the baby.

Occiput posterior (OP)

• The baby enters the pelvis with its head down but facing the mother's front or abdomen.
• In general, approximately 10 to 34 percent of babies remain in the OP position during the first stage of labor before shifting to the optimal (OA) position.
• However, some babies remain in this position, which can make labor difficult and necessitate an emergency Cesarean delivery.
• This fetal position can cause labor to be prolonged, resulting in instrumental interventions, severe perineal tears, or Cesarean delivery.

The cephalic presentation or head-first positions are referred to as OA and OP.

Occiput transverse (OT)

• In the womb, the baby is lying sideways, and if they do not turn to the optimal position in time for birth, a Cesarean delivery is required.
• During a vaginal examination, the doctor may feel the shoulder, arm, elbow, or hand protruding into the vagina.
• This baby position increases the risk of umbilical cord prolapse, which occurs when the umbilical cord protrudes before the baby.
• Cord prolapse can occur in about one percent of babies in the transverse position, which is a medical emergency that necessitates an immediate Cesarean delivery.
• In some cases, assisted delivery is performed by manually rotating the baby or using forceps or a vacuum to position the baby in the ideal position.

Umbilical cord presentation

• During this time, the umbilical cord is the first to emerge from the birth canal.
• The condition of the uterine membrane, however, distinguishes umbilical cord presentation from prolapse.
• A cord presentation occurs when the umbilical cord enters the birth canal before the water breaks, whereas a cord prolapse occurs after the water breaks, necessitating an emergency Cesarean delivery.

Breech position

The infant is positioned with its buttocks directed toward the birth canal, resulting in the following types of breech positions:

• Complete breech
  • The buttocks are pointing toward the birth canal, with the legs folded at the knees and the feet close to the buttocks.
  • In a vaginal delivery, this position increases the risk of an umbilical cord loop. Furthermore, the cord may pass through the cervix before the head, injuring the baby.
• Frank breech
  • The buttocks are pointing toward the birth canal with the legs straight up and the feet reaching the head.
  • This can result in an umbilical cord loop, which can injure the baby during vaginal birth.
• Footling breech
  • The baby's buttocks are pointing down, and one of their feet is pointing toward the birthing canal.
  • This can result in an umbilical cord prolapse, which can cut off the fetus' blood supply and oxygen supply.

A clinical examination of the abdomen, a vaginal examination, or an ultrasound examination is used to determine the position and presentation of the fetus during pregnancy.