Progesterone is a hormone that plays an important role in several stages of the reproductive process. First, progesterone helps to prepare the endometrium for implantation of the embryo. The endometrium must thicken, become more vascular, and secrete nourishing substances in order to support a developing fetus.

Once the eggs are ovulated, the corpus luteum produces progesterone. Once progesterone levels are elevated, it is a sign that ovulation has occurred.

After the embryo implants, the placenta produces progesterone to continue to support the fetus throughout the pregnancy.

Progesterone FAQ

What happens if I’m not producing enough progesterone?

If the placenta produces an insufficient amount of progesterone it could cause "luteal phase defect", which is thought to be associated with underdevelopment of the endometrium.

Poor progesterone levels during early pregnancy can also mark a risk of miscarriage or ectopic pregnancy (pregnancy outside of the uterus).

During IVF cycles, progesterone supplementation is prescribed until the pregnancy test and for an additional four weeks if the pregnancy test is positive.

These defects and fertility problems may be reduced by supplemental progesterone.