Initiation of Parturition in Humans

Initiation of parturition or the onset of labor in humans is a complex process that involves various hormonal and physiological changes in the mother and the fetus. The process of parturition is triggered by a series of events, including the synthesis of prostaglandins, release of oxytocin, and changes in estrogen and progesterone levels.

Components of Initiation of Parturition

1. Synthesis of Prostaglandins
- Prostaglandins are lipid compounds that are produced by the uterus and the fetal membranes.
- During pregnancy, the levels of prostaglandins increase, which helps to maintain the pregnancy by promoting uterine quiescence.
- As the due date approaches, the levels of prostaglandins increase further, which leads to cervical ripening, uterine contractions, and the onset of labor.

2. Release of Oxytocin
- Oxytocin is a hormone that is produced by the hypothalamus and released by the posterior pituitary gland.
- During labor, oxytocin stimulates uterine contractions, which helps to progress labor and deliver the baby.
- The release of oxytocin is triggered by various stimuli, including cervical dilation, fetal distress, and maternal stress.

3. Increase in Estrogen and Progesterone Ratio
- During pregnancy, the levels of estrogen and progesterone increase, which helps to maintain the pregnancy and promote fetal growth.
- As the due date approaches, the levels of estrogen increase further, which leads to an increase in the estrogen to progesterone ratio.
- The increase in the estrogen to progesterone ratio promotes uterine contractions and cervical ripening, which helps to initiate labor.

4. Release of Prolactin
- Prolactin is a hormone that is produced by the anterior pituitary gland and plays a role in lactation.
- Prolactin levels increase during pregnancy and continue to increase after delivery to promote milk production.
- However, prolactin is not considered an important component of initiation of parturition as it does not play a direct role in triggering labor.

Answer

The correct answer is option 'C', release of prolactin. Prolactin is not considered an important component of initiation of parturition as it does not play a direct role in triggering labor. The other options - synthesis of prostaglandins, release of oxytocin, and increase in estrogen and progesterone ratio - are important components of initiation of parturition in humans.

Release of prolactin induces formation of milk in the mammary gland so it has no effect on parturition... other hormones r necessary for parturition