Third Stage of Labour — Acute Management

1. Recognition of Placental Separation

• The uterus becomes globular and firmer as it contracts
• A sudden gush of blood as the placenta separates from the uterine wall
• The umbilical cord lengthens and protrudes further from the vagina
• The fundal height rises in the abdomen

2. Active vs. Expectant Management

Never attempt to deliver the placenta before separation occurs. Never use forceful cord traction — this risks cord avulsion or uterine inversion, a catastrophic complication.

3. Uterotonic Agents

• 10 units IM after delivery of the placenta (preferred)
• IV option: 5–10 units slow IV bolus, then infusion of 10 units/hr (up to 40 units total in 1L normal saline at 10 mL/min until uterus contracts, then reduce to 1–2 mL/min)
• ⚠️ Do not give IV oxytocin as a rapid bolus — causes hypotension

• Methylergonovine (Methergine) 0.2 mg IM every 20 minutes, or
• Ergonovine maleate 0.2 mg IM
• ⚠️ Contraindicated in hypertension (including pregnancy-associated hypertension) due to vasoconstrictive properties

• PGF₂α (carboprost/Hemabate) 250 μg IM every 15–20 minutes, up to 3 doses
• Misoprostol 200–1000 μg (oral, sublingual, vaginal, or rectal) — widely used off-label; increases uterine tone and reduces bleeding; use with caution in cardiovascular disease; may cause nausea, vomiting, pyrexia, diarrhea at high doses

4. Placenta Delivery Technique

1. Ask the mother to bear down — intraabdominal pressure may suffice
2. Confirm uterus is firmly contracted and separation has occurred
3. With one hand on the abdominal wall lifting the fundus cephalad (suprapubic pressure), apply gentle traction on the cord with the other hand
4. Once the placenta reaches the introitus, stop uterine pressure and gently lift the placenta upward and out

5. Post-delivery Inspection

• Inspect the placenta for completeness — any defect or missing cotyledon suggests retained products of conception (causes ~10% of PPH cases)
• Check the cord: normally a 3-vessel structure (2 arteries, 1 vein); a 2-vessel cord warrants follow-up
• Inspect cervix, vagina, vulva, and perineum for lacerations
  • 1st degree: skin/mucosa only
  • 2nd degree: fascia and perineal muscles
  • 3rd degree: into anal sphincter
  • 4th degree: through rectal mucosa (3rd & 4th → repair in OR by obstetrician)
• Encourage early breastfeeding — stimulates endogenous oxytocin, maintains uterine contraction

6. Immediate PPH Management (if it occurs)

1. Bimanual uterine massage — one hand transabdominally, one supports uterus through introitus
2. Uterotonic agents (as above)
3. Blood type & cross-match; use O-negative unmatched blood in emergencies
4. Rule out: retained placental fragments (ultrasound), birth trauma/lacerations, coagulopathy

Key Pitfalls to Avoid

• Oxytocin before placenta delivery → may trap placental fragments or an undetected twin
• Premature or forceful cord traction → uterine inversion
• Incomplete placenta inspection → retained products → delayed PPH

• ROSEN's Emergency Medicine: Concepts and Clinical Practice
• Roberts and Hedges' Clinical Procedures in Emergency Medicine
• Textbook of Family Medicine, 9e