Factors which help in descent of the presenting part during labour are all except:

Ans. is d, i.e. Resistance from the pelvic floorRef Dutta Obs. 7/e, p 124Descent: Descent is a continuous process provided there is no undue bony or soft tissue obstruction. It is slow or insignificant in first stage but pronounced in second stage. It is completed with the expulsion of the fetus. In primigravidae, with prior engagement of the head, there is practically no descent in first stage; while in multiparae, descent starts with engagement. Head is expected to reach the pelvic floor by the time the cervix is fully dilated.Factors facilitating descent are--(1) uterine contraction and retraction, (2) bearing down efforts and (3) straightening of the fetal ovoid specially after rupture of the membranes.Note: Resistance offered by the pelvic floor promotes flexion of head and not descent.