Stages of Labour - Summary

FIRST STAGE: Onset of Labour → Full Cervical Dilation (10 cm)

• Cervical dilation: 0 to 3-4 cm
• Cervical effacement, softening, anterior positioning
• Duration: up to 20 hrs (nullipara) / up to 14 hrs (multipara)
• Contractions become regular but mild-moderate
• Best managed at home; hospital if: bleeding, SROM, contractions 3-4 min apart, decreased fetal movement

• Dilation: 4 cm → 10 cm (full)
• Rate: ≥ 1.2 cm/hr (nullipara), ≥ 1.5 cm/hr (multipara) - Friedman curve
• Duration: ~4.6 hrs (nullipara), ~2.4 hrs (multipara)
• Cardinal movements begin: Engagement → Descent → Flexion → Internal rotation
• FHR monitoring every 30 min (low risk), every 15 min (high risk)

• Prolonged latent phase: > 20 hrs (nullipara) / > 14 hrs (multipara) - treat with morphine
• Protracted active phase: dilation < 1.2 cm/hr (nullipara) or < 1.5 cm/hr (multipara)
• Arrest of active phase: no dilation for ≥ 2 hours

SECOND STAGE: Full Dilation → Delivery of Baby

• Active maternal expulsive forces (pushing)
• Cardinal movements continue: Extension → External rotation → Expulsion
• Duration: avg 50 min (nullipara) / avg 20 min (multipara)
• FHR auscultated every 15 min (low risk) / every 10 min (high risk)
• Alert if pushing > 2 hrs without epidural OR > 3 hrs with epidural (nullipara) - possible CPD

THIRD STAGE: Delivery of Baby → Delivery of Placenta

• Signs of placental separation: cord lengthening, gush of blood, change in fundal contour
• Active management: Oxytocin + controlled cord traction + uterine massage
• Duration: typically within 30 minutes
• Inspect for vaginal/cervical tears after placenta delivers

FOURTH STAGE: 1st Hour After Placental Delivery (Pritchard & MacDonald)

• Monitor for PPH, uterine atony, vital signs
• Uterine massage; oxytocin 20-40 units/L IV or 20 units IM
• Alternatives: methylergonovine 0.2 mg IM (if not hypertensive); PGF₂α (Hemabate) 250 mcg IM
• Misoprostol 200-1000 mcg (oral/SL/vaginal/rectal) - widely used off-label
• Repair of episiotomy and perineal lacerations