Labor and Birth
Stages, cervical change, induction, and labor emergencies
Stages of labor
| Stage | From → to | Key points |
|---|---|---|
| 1st: latent phase | Onset → 6 cm | Slower, irregular progress; rest, hydrate, walk |
| 1st: active phase | 6 cm → 10 cm | Faster dilation; stronger, regular contractions; transition (8–10 cm): nausea, shaking, urge to push |
| 2nd | 10 cm → birth of baby | Pushing; monitor FHR more often |
| 3rd | Birth → delivery of placenta | Usually <30 min. Separation signs: gush of blood, cord lengthens, uterus rises and becomes globular |
| 4th | First 1–2 h after placenta | Recovery: VS and fundus every 15 min in the first hour; highest risk of hemorrhage |
Cervix and fetal position
- Dilation 0–10 cm; effacement 0–100% (thinning).
- Station: −5 to +5; 0 = at the ischial spines (engaged).
- Most common position: LOA (left occiput anterior). Posterior (OP) → back labor.
- Contraction frequency = start of one to start of the next; duration = start to end of one.
- Tachysystole: >5 contractions in 10 min, averaged over 30 min.
True vs. false labor
| True | False |
|---|---|
| Regular, closer together, stronger | Irregular, no pattern |
| Continues with walking or rest | Eases with rest, fluids, position change |
| Back pain moving to the front | Felt in front/abdomen |
| Cervix changes | No cervical change |
Rupture of membranes
- Check the FHR right away after rupture (cord prolapse risk).
- Note fluid COAT: Color (clear normal; green = meconium), Odor (foul = infection), Amount, Time.
- Nitrazine paper turns blue (alkaline amniotic fluid); ferning under the microscope.
- Rupture >18 h → infection risk: monitor temperature.
Induction and augmentation
- Bishop score ≥8 = favorable cervix. Lower → cervical ripening first.
- Misoprostol (PGE1) or dinoprostone (PGE2), or a balloon catheter. No misoprostol with a previous cesarean or uterine scar (rupture risk). Start oxytocin ≥4 h after the last misoprostol dose.
- Oxytocin (high-alert): infusion pump, piggybacked into the main line at the port closest to the patient. Titrate per protocol. Stop it for tachysystole with an abnormal FHR or a Category III tracing. Watch for water intoxication (headache, confusion, ↓ urine).
Preterm labor (<37 weeks)
- Tocolytics delay birth ~48 h to allow steroids and transfer: nifedipine; indomethacin (<32 wk, ≤48 h); terbutaline (short-term only: boxed warning against prolonged or oral use).
- Betamethasone 12 mg IM × 2 doses 24 h apart (24 0/7–33 6/7 wk; considered from 22 wk and in selected late-preterm cases) for fetal lung maturity.
- Magnesium sulfate before 32 wk for fetal neuroprotection.
Emergencies
Cord prolapse: call for help; gloved hand lifts the presenting part off the cord; knee-chest or Trendelenburg; don't push the cord back; keep it moist; emergency cesarean.
Shoulder dystocia: McRoberts (thighs to abdomen) + suprapubic pressure. Never fundal pressure.
Epidural hypotension: side-lying, IV fluid bolus, vasopressor as ordered; check the bladder.
Shoulder dystocia: McRoberts (thighs to abdomen) + suprapubic pressure. Never fundal pressure.
Epidural hypotension: side-lying, IV fluid bolus, vasopressor as ordered; check the bladder.