A 28-year-old primigravida at 36 weeks of gestation presents for a routine antenatal visit. Her blood pressure is 118/74 mmHg. Ultrasound shows the fetus in a cephalic presentation with the fetal head engaged in the maternal pelvis. Which of the following pelvic shapes is MOST associated with a smooth vaginal delivery in a cephalic presentation?
- A Gynaecoid ✓
- B Android
- C Anthropoid
- D Platypelloid
Correct answer: A. Gynaecoid
Explanation
The gynaecoid pelvis has a rounded inlet, adequate mid-pelvis, and wide subpubic arch (~90°), making it the most favourable for vaginal delivery in cephalic presentation. It is the most common pelvis type in females (~50%). Android and platypelloid pelvises are associated with dystocia and higher rates of operative delivery.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.