Layers of smooth muscle in the reproductive tract of the female are important in

There are choices for this question namely:

movement of oocytes 
movement of sperm if present 
expelling of the fetus at delivery 
all of the above

The correct answer is "all of the above". The smooth muscle layers in the female reproductive tract facilitates the movement of oocytes from the ampulla of the fallopian tube to the uterus. If sperm is present, the contraction of smooth muscle in the uterus will propel the sperm towards the fallopian tubes where it can fertilize the ovum. At delivery, uterine contractions (along with an adequate pelvis) facilitate the delivery of the fetus; without which the labor will be dysfunctional or prolonged and this is called dystocia.

They get pregnant at younger ages