. Foetal ejection reflex in human females is induced by
A: Release of oxytocin from pituitary
B: Pressure exerted by amniotic fluid
C: Differentiation of mammary glands
D: Fully developed foetus and placenta
Childbirth is an induced complex neuroendocrine mechanism. In this the signals originate from a fully developed embryo and placenta.
This causes a slight contraction in the uterus and hence the ejection reflex of the fetus. Oxytocin then acts on the muscles of the uterus causing stronger contractions of the uterus.
It continues to contract stronger and stronger. As a result, the baby is expelled from the uterus along with the placenta through the birth canal.
Therefore, foetal ejection reflex in human females is induced by fully developed foetus and placenta.
Final Answer :
Hence the correct answer is option (D).