Commonest cause of nonengagement at term, in primi is:

Ans. is a, i.e. CPDRef. Dutta Obs. 7/e, p 81, 82, 352Engagement is said to occur when the greatest transverse diameter of the presenting part, has passed through the pelvic inlet In all cephalic presentations, the greatest transverse diameter is always the biparietal.Engagement occurs in multipara with commencement of labourQ in the late 1st stage after rupture of membranes and in Nullipara during the last few weeks of pregnancy, i.e. [?] 38 weeksIn primi's the most common cause of non engagement at term is deflexed head or occipitoposterior position followed by cephalopelvic disproportion (CPD). QSince deflexed head or occipitoposterior is not given in option, we will go for CPD as the answer.