Progesterone is made in the ovaries, corpus luteum, placenta, and the adrenal glands. The main way we make progesterone on a regular basis is by ovulating during our menstrual cycles.

Progesterone, like estrogen, is an important hormone for your health. It has numerous roles in the body:

• it causes the uterine lining to stay thick and stable in the 2nd half of your menstrual cycle to allow for egg implantation
• it decreases uterine contractions
• it supports blood flow to the uterus
• it helps maintain pregnancy and low progesterone is implicated in recurrent pregnancy loss and unexplained infertility
• it increases the process of bone formation
• it supports brain cell survival
• it has anti-inflammatory properties
• it balances out i.e. opposes the effects of estrogen
• it makes cervical mucus tackier and thicker in the second half of the cycle creating a less hospitable environment for sperm (and anything else that might get in vaginally