Question

A woman is in the second stage of labor and is crowning. Which diameter of the fetal skull, which is the smallest, should align with the anteroposterior diameter of the mother's pelvis, which is the narrowest diameter at the pelvic inlet.

Answer 1

Answer: Sub-occipitobregmatic of 9.5cm

Explanation: during the second stage of labour, there is increased descent and flexion of the foetus due to increased uterine contraction.

The result of increased foetal flexiin is that the presenting part becomes smaller to be able to negotiate with the pelvis more easily.

The occiput of the foetus becomes the leading part and escapes under the symphysis pubis and crowning is said to have occurred.