Stages of Labor

Labor = the process of uterine contractions that cause progressive cervical change (dilation and effacement) and eventual delivery of the fetus, placenta, and membranes. Four Stages of Labor: First Stage: Onset of regular contractions → complete cervical dilation (10 cm) - Latent phase: 0–6 cm; slow progress; variable duration; painful but manageable - Active phase: 6–10 cm; faster progress (≥1 cm/hr nullipara; ≥1.2 cm/hr multipara in older guidelines) - Nullipara: typically 0.5–1 cm/hr (new ACOG guidelines more permissive) - Multipara: typically faster Second Stage: Complete dilation → delivery of infant - Nullipara without epidural: ≤2 hours - Nullipara with epidural: ≤3 hours - Multipara without epidural: ≤1 hour - Multipara with epidural: ≤2 hours - "Pushing" phase; crowning to delivery Third Stage: Delivery of infant → delivery of placenta - Normal: within 30 minutes - Managed: oxytocin administration + cord traction + uterine massage - Signs of placental separation: fundal rise, lengthening of cord, gush of blood, uterus becomes globular Fourth Stage: Delivery of placenta → 1–4 hours postpartum - Critical monitoring period for PPH - Uterine involution assessment -...