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How does progesterone prepare the uterus for implantation?
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Animal reproductive system
The process of sexual reproduction and several forms of parthenogenesis.
Progesterone is a vital hormone that regulates the endometrium, or the inner lining of the uterus, to ensure it is receptive to a fertilized egg. Produced primarily by the corpus luteum in the ovaries, progesterone prepares the uterine wall for implantation through several key physiological changes:1
- Nutrient and Blood Supply: It increases the blood supply and water content within the uterine wall and stimulates the secretion of glycogen, which serves as a necessary nutrient for the developing egg.2
- Muscular Inhibition: It inhibits muscular contractions of the uterus that would otherwise risk rejecting the adhering egg.12
- Structural Support: It promotes the thickening and active secretion of the endometrium, creating a suitable environment for the blastocyst to attach and embed.3
If the uterus is not adequately prepared by progesterone, the egg will fail to attach. If fertilization does not occur, progesterone levels drop, leading to the breakdown of the uterine lining and the onset of menstruation.213