II. Definition
- Abnormal Fetal Position with occiput at maternal Sacrum
- Fetal face towards maternal Symphysis Pubis
III. Epidemiology
- Represents 10% of Fetal Positions
IV. Physiology
- Less favorable fetal head diameter for delivery
- Deflexion of fetal head
- Posterior presentation
- Usually corrects spontaneously
- Rotates to Occiput Anterior position in 90% of cases
V. Symptoms
- Back labor
- Prolonged labor
- Nulliparous: Additional two hours
- Multiparous: Additional one hour
VI. Signs: Digital cervical exam
VII. Complications
- Failure to Progress
- Extended episiotomy or perineal Laceration
VIII. Management
- Spontaneous Delivery (anticipate in 45% of cases)
- Maternal position changes (unclear efficacy)
- Any position in which mother curls forward from hips
- Hands and knees
- Squatting
- Manual rotation during vaginal exam
- Vacuum Delivery
- Place vacuum cup as posterior as possible
- Inproves flexion of fetal head
- Do not use vacuum to rotate fetal head
- Results in Scalp Laceration
- Place vacuum cup as posterior as possible
- Forceps Delivery
- Forceps Rotation (skilled clinician only)
- Techniques: Scanzoni or Kielland
- Requires immediate Ceserean back-up
- Rarely performed in U.S. now