The following pelvis is usually associated with transverse arrest:-
A. Anthropoid
B. Android
C. Gynecoid
D. Platypelloid
Correct Answer: B. Android
Transverse arrest is usually associated with the 👉 Android pelvis.
Explanation
- Android pelvis has:
- Heart-shaped pelvic brim
- Narrow forepelvis
- Prominent ischial spines
- Narrow mid-pelvis
- Because of the narrow mid-pelvis and prominent spines, the fetal head often fails to rotate from the transverse position to the anteroposterior diameter.
- This leads to persistent occipito-transverse position, resulting in transverse arrest of labor.
Summary
Pelvic type Association AndroidTransverse arrest (most common) Gynecoid Normal rotation & vaginal delivery Anthropoid Occipito-posterior positions Platypelloid Engagement difficulty
✅ Correct answer: Android pelvis
Other Options Details
Here is a clear description of all four pelvic types, commonly asked in obstetrics and anatomy:
A. Anthropoid pelvis (Ape type)
- Pelvic inlet shape: Oval, anteroposterior diameter > transverse
- Sacrum: Long and deeply curved
- Side walls: Straight
- Ischial spines: Not very prominent
- Subpubic angle: Moderately wide
- Obstetric significance:
- Fetal head often enters in anteroposterior position
- Vaginal delivery usually possible but occiput posterior positions are common
B. Android pelvis (Male type)
- Pelvic inlet shape: Heart-shaped
- Forepelvis: Narrow
- Side walls: Convergent
- Ischial spines: Prominent
- Subpubic angle: Narrow (< 90°)
- Sacrum: Short, flat, and inclined forward
- Obstetric significance:
- Least favorable for vaginal delivery
- Increased risk of obstructed labor, deep transverse arrest, and operative delivery
C. Gynecoid pelvis (Female type – ideal pelvis)
- Pelvic inlet shape: Round or transversely oval
- Side walls: Straight
- Ischial spines: Blunt and not prominent
- Sacrum: Wide and well curved
- Subpubic angle: Wide (> 90°)
- Obstetric significance:
- Most common and most favorable pelvis for normal vaginal delivery
D. Platypelloid pelvis (Flat type)
- Pelvic inlet shape: Transversely oval / flat
- Anteroposterior diameter: Reduced
- Transverse diameter: Increased
- Sacrum: Flat
- Side walls: Wide apart
- Obstetric significance:
- Engagement of fetal head is difficult
- Labor may be prolonged and operative delivery is more common
Summary Table
Pelvis Type Inlet Shape Delivery Outcome Gynecoid Round Best for vaginal delivery Anthropoid AP oval OP positions common Android Heart-shaped Difficult labor Platypelloid Flat transverse Delayed engagement
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Writer: Vandita Singh, Lucknow (GS India Nursing Group