A primigravida presents to the labor room at 40 weeks of gestation with lower abdominal pain. She has been in labor for 3 hours. Which of the following will determine if she is in active labor?

Cervical dilatation of 6 cm or more with regular contractions

Fetal head 5/5 palpable on abdominal examination

Two contractions lasting for 10 seconds in 10 minutes

What procedure is being demonstrated in the image?

Artificial rupture of membranes

Abortions in the second trimester mainly occur due to

congenital anomalies of the foetus

congenital anomalies of the uterus

Preterm Labor and Delivery for NEET-PG: High-Yield Obstetrics and Gynecology Lessons

PTL: Definition & Risks - Defining Danger

Definition: Regular uterine contractions + cervical changes (dilatation/effacement) at Gestational Age (GA) < 37 0/7 weeks.
Key Risk Factors:
- Previous preterm birth (PTB).
- Multiple gestation (twins, triplets).
- Infections (e.g., UTI, BV).
- Preterm Prelabor Rupture of Membranes (PPROM).
- Cervical incompetence / short cervix (< 25 mm mid-trimester).
- Uterine overdistension (polyhydramnios).
- Placental issues (abruption, previa).
- Maternal: smoking, extremes of age, low SES.

⭐ Strongest risk factor for PTL is a history of prior spontaneous preterm birth.

PTL: Diagnosis & Prediction - Catching It Quick

Clinical Diagnosis:
- Uterine contractions: ≥4 in 20 min or ≥8 in 60 min
- AND Documented cervical change:
  - Dilatation ≥2 cm
  - Effacement ≥80%
  - Cervical length (CL) <25mm via TVS
Prediction Markers:
- History: Prior PTL (strongest predictor).
- Biochemical Markers:
  - fFN: Positive if >50 ng/mL (22-34 wks).
  - PIGFBP-1.
  - PAMG-1.
- Biophysical:
  - TVS Cervical Length (CL): <25mm (16-24 wks) indicates ↑ risk.

⭐ Negative fFN test: High NPV (97-99%) for ruling out delivery within 7-14 days.

PTL: Tocolysis - Hitting Pause

📌 Mnemonic: 'It''s Not My Time' (Indomethacin, Nifedipine, Magnesium Sulfate, Terbutaline/Atosiban)

Tocolytics Comparison:

Tocolytic	MOA	Dose (Brief)	Key SEs	Key CIs / GA Limit
Indomethacin	↓PG synth	Load; ≤48h	PDA closure, Oligo	≥32 wks, NSAID allergy
Nifedipine	Ca²⁺ Blocker	10-20mg PO	Hypotension, Headache	Cardiac dz, Hypotension
$MgSO_4$	Ca²⁺ Antag.	IV Load+Maint.	Flushing, Resp. dep.	Myasthenia, Renal fail.
Terbutaline	β₂-Agonist	0.25mg SC	Tachycardia, Pulm. edema	Cardiac dz, Uncontrolled DM
Atosiban	Oxytocin Antag.	IV Bolus+Inf.	Nausea, Headache (mild)	Allergy

⭐ > First-line tocolytic for GA <32 weeks is Indomethacin, but it's contraindicated after 32 weeks due to risk of premature ductus arteriosus closure.

PTL: Fetal Care & Prevention - Guarding Futures

Antenatal Corticosteroids (ACS): Fetal lung maturity; PTL 24-34 wks.
Drug Regimen
Betamethasone 12 mg IM, 2 doses 24 hrs apart
Dexamethasone 6 mg IM, 4 doses 12 hrs apart
Magnesium Sulfate ($MgSO_4$): Neuroprotection <32 wks GA.
Prevention Strategies:
- Progesterone (vaginal/IM): Prior PTL or short cervix (<25 mm).
- Cervical Cerclage: History-indicated (prior PTL) or USG-indicated short cervix.

Drug	Regimen
Betamethasone	12 mg IM, 2 doses 24 hrs apart
Dexamethasone	6 mg IM, 4 doses 12 hrs apart

⭐ ACS significantly reduces risks of Respiratory Distress Syndrome (RDS), Intraventricular Hemorrhage (IVH), and Necrotizing Enterocolitis (NEC) in preterm neonates.

High‑Yield Points - ⚡ Biggest Takeaways

Preterm labor: Regular contractions with cervical changes from 20 to <37 weeks gestation.

Fetal fibronectin (fFN): High negative predictive value for ruling out imminent preterm delivery.

Cervical length <25 mm on TVS is a major risk factor for preterm birth.

Tocolytics (e.g., Nifedipine) delay delivery for 48 hours to allow corticosteroid administration.

Antenatal corticosteroids (Betamethasone) are crucial for fetal lung maturity if <34 weeks.

Magnesium sulfate offers neuroprotection for fetuses delivered <32 weeks.

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