It is a hormone secreted from the corpus luteum of the ovary during the second half of the menstrual cycle. Luteinizing hormone (LH) helps make and secrete progesterone from the corpus luteum. It is secreted just before ovulation from the follicle(s) that will release an egg. It helps the uterus accept and keep a pregnancy.
Progesterone therapy can be used to replace or supplement the natural hormone. It can cause changes in the uterine lining like a natural menstrual cycle.
3 days after a positive OPK or 2 days after insemination, you start taking progesterone vaginally. Use 1 capsule 2 times each day for 14 days. Take a home pregnancy test and call the clinic with your results after 14 days.
You do not have to lie down after putting progesterone in the vagina. You may want to wear a panty liner for comfort.
The risk of taking it early in pregnancy and having a baby with birth defects is not totally known. Studies are showing the risks would be small if there are any at all.
Talk with your nurse or doctor about any concerns.