The Effects of Decreased Progesterone

Progesterone is a hormone essential to sexual health. Progesterone regulates menstruation and breast development, plays a role in female fertility and performs a range of functions in other tissues. Progesterone is produced in the adrenal glands and ovaries, as well as in the placenta during pregnancy. The body tightly regulates progesterone levels, and low levels of progesterone can lead to a deleterious effects.


Progesterone plays a natural role in regulating mood owing to its effect on a chemical called serotonin. Serotinin is a neurotransmitter—a protein found in the brain that facilitates signaling between nerve cells. Too little serotonin leads to mood disturbances and depression. The Oregon Health and Science University, or OHSU, reports that low levels of progesterone are associated with low levels of serotonin in the brain, so low progesterone levels can lead to depression.

Dr. Cynthia Bethea at OHSU explains that progesterone leads to the production of more serotonin the brain, increasing the overall levels of serotonin. Progesterone also promotes the survival of brain cells that respond to serotonin, increasing serotonin signaling to fight depression further. Patients with low progesterone levels may experience depression related to the loss of these depression-fighting mechanisms.

Irregular Menstruation

The cycling of estrogen and progesterone helps regulate a woman’s menstrual cycle to allow for regular ovulation and menstruation. Specifically, progesterone plays a role in preparing the lining of the uterus for the implantation of a fertilized egg after ovulation and affects the levels of other hormones that play a role in menstruation. Low levels of progesterone lead to irregular periods because the uterus does not receive the proper signals to continue the menstrual cycle. The loss of progesterone also leads to imbalances in other hormones that affect menstruation. Restoring progesterone levels with hormone replacement therapy usually restores regular menstruation.

Sexual Dysfunction

Low progesterone levels may also lead to sexual dysfunction. Progesterone, along with several other hormones, plays a role in facilitating female sexual function, so the loss of progesterone is often accompanied by sexual symptoms. A 2004 study published in the “Journal of Sexual Medicine” indicates that a loss of sex hormones such as progesterone can lead to decreased sex drive, pain during sex and difficulty achieving orgasm. Low progesterone also plays a role in erectile dysfunction in men. Hormone therapy to supplement levels of progesterone can alleviate the sexual symptoms associated with low progesterone levels.

About this Author

Louise Tremblay recently finished an M.Sc. in molecular and cellular biology in Ontario, Canada, with years of cancer research experience. She has experience writing articles and Web content on science, heath and fitness, diet and personal wellness.