Management of Occiput Posterior (OP) Presentation

1. Recognition / Diagnosis

• Labor pain predominantly felt in the back ("back labor")
• Persistent anterior cervical lip despite adequate labor progress
• Easily palpable anterior fontanelle (large, cross-shaped) on vaginal examination
• Prolonged second stage without descent

• Follow the infant's skull sutures until the posterior fontanelle (small, Y-shaped) can be located - in OP, it faces posteriorly toward the sacrum
• Intrapartum ultrasound (transperineal probe, transverse plane) is now the gold standard for confirming fetal head position when clinical examination is uncertain
• Rotation is less than or equal to 45 degrees (left or right occiput anterior to OA, or left or right OP to OP) on classification

2. Conservative / Expectant Management

• Fetal heart rate is reassuring
• Labor is progressing (even if slowly)
• No indication for immediate intervention

Maternal Positioning

3. Manual Rotation

1. Place mother in lithotomy, lateral Sims', or hands and knees position
2. Insert the dominant hand into the posterior pelvis behind the occiput
3. During a contraction with maternal pushing, attempt to rotate and flex the head toward OA
4. If the fetus is direct (straight) OP - use the dominant hand
5. If the fetus is partially rotated - use whichever hand most easily rotates it in the direction of shortest distance to OA

4. Instrumental Delivery

Vacuum Extraction

• Apply vacuum cup over the posterior fontanelle (or over the sagittal suture up to 3 cm anterior to the posterior fontanelle)
• The vacuum can assist rotation from OP to OA during traction
• For OP deliveries specifically, the vacuum handle may point toward the floor during traction (due to altered angles compared to OA deliveries)
• Do not rock or torque the cup - only steady, gentle traction

• A - Adequate anesthesia
• B - Bladder empty
• C - Cervix completely dilated
• D - Determine position (confirm OP by palpation/ultrasound)
• E - Equipment ready
• F - Fix cup over posterior fontanelle
• G - Gentle traction with contractions

Forceps Delivery

• For OP, rotation forceps (e.g., Kielland's) can be used to rotate from OP to OA before traction
• Classification: OP is rotation ≤45 degrees from posterior to posterior, or the operator may rotate to OA
• Outlet forceps may also be used for face-to-pubis (direct OP) delivery - the fetus delivers with the face facing upward

5. Delivery in Persistent OP ("Face-to-Pubis")

• The fetal occiput descends toward the perineum and the face sweeps under the symphysis
• A larger presenting diameter (occipito-frontal, ~11.5 cm vs. suboccipito-bregmatic ~9.5 cm in OA) passes through the pelvis
• This is associated with a higher rate of perineal tears (including 3rd and 4th degree)
• Episiotomy may be considered to reduce the risk of severe perineal lacerations, though evidence is mixed

6. Cesarean Section

• Labor arrest persists: no cervical change for 2 hours with adequate contractions (or 2-4 hours of oxytocin augmentation without progress)
• Instrumental delivery is not feasible or fails
• Fetal distress (non-reassuring CTG)
• Absolute cephalopelvic disproportion (CPD)
• Failed manual/instrumental rotation

7. Augmentation

• Oxytocin augmentation can be used if labor arrest occurs during either the first or second stage
• An intrauterine pressure catheter (IUPC) may be inserted to objectively assess contraction adequacy
• Arrest = no cervical change with adequate contractions for 2 hours

Summary Algorithm

OP Diagnosed
     │
     ├─► Fetal heart rate reassuring?
     │         YES → Expectant management + maternal positioning
     │         NO  → Expedite delivery
     │
     ├─► Labor progressing?
     │         YES → Continue monitoring, encourage positions
     │         NO  → Augment with oxytocin
     │
     ├─► Second stage - attempt manual rotation
     │         Success → Continue to vaginal delivery (OA)
     │         Fail    → Instrumental delivery (vacuum/forceps)
     │                        └── Fail or not feasible → Cesarean
     │
     └─► Persistent OP with descent → Face-to-pubis delivery
                                        (higher perineal tear risk)

• Most OP positions rotate spontaneously to OA - patience is key
• Back pain in labor is a classic symptom
• Maternal repositioning (hands and knees) is the first-line conservative approach
• Manual rotation should be attempted before instrumental delivery
• If all else fails, direct OP delivery face-to-pubis is possible but carries greater maternal morbidity
• Cesarean is indicated for labor arrest, failed instrumental delivery, or fetal compromise