Uterine Size at 9 Months (Term Pregnancy): Anatomy and Maternal Effects

At term (≈40 weeks), the uterus measures roughly 30–35 cm fundal height and approximates the size of a small watermelon or large melon.

Anatomic Changes

• Fundus reaches xiphoid process / costal margin.
• Capacity expands from ~10 mL to ~5 L.
• Wall thickens then thins (hypertrophy → stretching).

Maternal Physiologic Impact

• Diaphragm elevation → dyspnea, reduced lung volumes.
• Bladder compression → frequency, urgency.
• Aortocaval compression (supine) → hypotension.
• Gastroesophageal reflux (increased intra‑abdominal pressure).

Clinical Monitoring

• Fundal height (cm) ≈ gestational weeks (±2 cm).
• Leopold's maneuvers for lie, presentation, engagement.
• Ultrasound for growth, fluid, placental position.