Question

Define Parturition. Give an account of different hormones involved during this process.

Hint:

Progesterone maintains pregnancy, but a drop in its level along with rise in oxytocin and prostaglandins triggers parturition.

Answer 1

Definition: Parturition is the process of expelling the fully developed fetus from the mother's uterus at the end of gestation (childbirth). Hormonal Control of Parturition: \begin{enumerate} \item Oxytocin: Secreted by the posterior pituitary. Stimulates strong uterine contractions during labor. \item Relaxin: Relaxes the ligaments of the pelvic region and softens the cervix for easy passage of the baby. \item Estrogen and Progesterone: During pregnancy, progesterone inhibits uterine contractions. Near parturition, progesterone decreases while estrogen increases, stimulating uterine contractions. \item Prostaglandins: Enhance contraction of uterine muscles and work synergistically with oxytocin. \end{enumerate} Conclusion: Thus, parturition is a neuro-endocrine mechanism regulated by maternal and fetal signals involving hormones like oxytocin, estrogen, progesterone, relaxin, and prostaglandins.