Why is Progesterone used for IVF?
Progesterone is required for the success of early pregnancy. In a natural cycle progesterone is made by the corpus luteum (CL). If the CL is removed during the first 5 weeks after conception, the pregnancy will miscarry. By about 9 weeks’ gestation, the luteal-placental shift takes place: the trophoblast itself makes sufficient progesterone, and the pregnancy is no longer dependent on the CL. There are 2 reasons for giving extra progesterone after an IVF. The first is that the CLs in IVF were all disturbed by the IVF needle during egg pick-up. The CLs start as follicles containing eggs. At the retrieval, the needle is placed inside the follicle, the egg is removed; and other cells may also be removed. The follicle is mostly fluid, but it also contains tons of cells that make up the follicle and surround the egg. These are called the granulosa cells; and these are the cells that convert to CL cells after ovulation. So if the needle removes some of these cells, as is usually the case, th
