A fully developed foetus initiates its delivery from the mother’s womb. Justify the statement.

Explanation

• The signals for parturition originate from the fully developed foetus and the placenta which induce mild uterine contractions called foetal ejection reflex.
• This triggers the release of oxytocin from the maternal pituitary.
• Oxytocin acts on the uterine muscle and causes stronger uterine contractions, which in turn stimulates further secretion of oxytocin.
• The stimulatory reflex between the uterine contraction and oxytocin secretion continues resulting in stronger and stronger contractions.
• Parturition is induced by a complex neuroendocrine mechanism involving cortisol, oestrogens and oxytocin.
• This leads to expulsion of the baby out of the uterus through the birth canal – parturition.