Which among the following hormones causes stronger uterine contractions during the birth of a baby?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Oxytocin.
Parturition is the delivery of the baby at the end of pregnancy. It is started by a neuroendocrine reflex. The fully developed foetus and the placenta send signals that cause mild contractions of the uterus. These contractions make the mother’s pituitary release oxytocin. Oxytocin acts on the muscle of the uterus and makes the contractions stronger. Stronger contractions cause more oxytocin to be released, so the contractions keep growing until the baby is pushed out through the birth canal.
NCERT Extract:
Parturition and Lactation – “… Parturition is induced by a complex neuroendocrine mechanism. The signals for parturition originate from the fully developed foetus and the placenta which induce mild uterine contractions called foetal ejection reflex. This triggers 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.”