Question

What is partiturition? Which hormones are involved in induction of parturition?

Answer 1

Hint: Parturition is the process of delivering a baby or child from the uterus under the influence of some hormones.

Complete Answer:
- Parturition or childbirth is the action or process of giving birth to a child or offspring. It is due to the result of changes in hormone levels circulating in both mother and child’s body at the end of pregnancy.
- It can be basically said the mechanism of signaling the onset of labor or procedure of delivering a child after the completion of pregnancy.
- During parturition, the cervix dilates and relaxes and the uterus contracts to push the fetus towards the cervix and continues to do so until the fetus comes down the birth canal.

The process of parturition consists of three stages:
1) Dilation - It is the first stage of parturition. It begins with the onset of labor and continues until the cervix dilates.
2) Expulsion - This stage starts at the beginning of dilation and continues until the birth of a child. It can be simply defined as delivery of the newborn.
3) Placental - This is the third stage of parturition. In this stage shedding of placenta occurs and contraction of the uterus decreases.

Hormones that are responsible for the induction of parturition are: oxytocin and relaxin.
- Oxytocin: It is secreted by the posterior pituitary gland. It facilitates uterine contractions to push foetus downward which in turn stretches the cervix. The amount of oxytocin is increased just before and during the labor pain.
- Relaxin- It is secreted by the corpus luteum after the completion of pregnancy. Its main function is to relax the pelvic ligament and cervix to facilitate the birth of a child.

Note: The secretion of milk is influenced by prolactin which is secreted by the anterior lobe of pituitary gland whereas ejection of milk is stimulated by oxytocin.