What is Progesterone?

It is one of the two main hormones produced every month by the ovaries of menstruating women, the other hormone is estrogen, men also produce a small amount of progesterone, but its production is not as important as that of testosterone (male sex hormone). It is the major female reproductive hormone which is produced naturally during the last 2 weeks of the menstrual cycle, its production is to enhance the chances of a woman becoming pregnant. It is made by the corpus luteum (according to the Stedman’s online medical dictionary, corpus luteum is the yellow endocrine body, 1–1.5 cm in diameter, formed in the ovary at the site of a ruptured ovarian follicle immediately after ovulation; there is an early stage of proliferation and vascularization before full maturity; later, there is a festooned and bright yellowish lutein zone traversed by trabeculae of theca interna containing numerous blood vessels; the corpus luteum secretes estrogen, as did the follicle, and also secretes progesterone. If pregnancy does not occur, it is called a corpus luteum spurium, which undergoes progressive retrogression to a corpus albicans. If pregnancy does occur, it is called a corpus luteum verum, which increases in size, persisting to the fifth or sixth month of pregnancy before retrogression. Syn: yellow body) of the ovary. It is normal for the levels of progesterone to rise and fall during the monthly cycle. Its production starts just before ovulation every month and increases swiftly after ovulation. This is what assists the fertilized egg(s) to survive. Just before ovulation the body temperature increases a little because of the rise in the progesterone level in the body, there is also an increase in the quantity of the mucus produced in the vagina which increases the chances of the sperm reaching the egg(s) in good time to fertilize it.