The causes of low progesterone levels in the body can be natural or due to an illness or disease. Progesterone is an important hormone for both men and women. In women, progesterone is a key part of the reproductive process. In men, progesterone is used to manufacture other hormones. A man's normal progesterone level is much lower than that of a woman during her reproductive years.
Menopause
Whereas a man's progesterone levels are fairly steady throughout his life, even into his 80s, a post-menopausal woman usually experiences a drop in progesterone levels. With the cessation of ovulation, a woman's progesterone level may drop to near zero. The abrupt drop in progesterone may be partially responsible for the lack of sex drive reported by some post-menopausal women.
Polycystic Ovarian Syndrome
Polycystic ovarian syndrome can cause a drop in a woman's progesterone level. PCOS most often affects a woman during her reproductive years. Typically, a woman with the disorder has a number of small cysts growing on both of her ovaries. The cysts interfere with ovulation and the production of progesterone. Other symptoms of PCOS include excessive hair growth, obesity and menstrual abnormalities, such as missed periods. Women with PCOS may be infertile or have difficulty getting pregnant.
Estrogen Dominance
Estrogen dominance describes an imbalance between estrogen and progesterone that can sometimes occur in women. In her book, "Women's Bodies, Women's Wisdom," Dr. Christine Northrup writes that estrogen dominance can be caused by stress, a high body mass index, or disease. Estrogen dominance can also occur naturally in women 35 years and older as they enter perimenopause, a transitional phase between the reproductive years and menopause. The lack of ovulation during some menstrual cycles can cause a build-up of estrogen in the body.
References
- "What Your Doctor May Not Tell You about Menopause"; John Lee, M.D.; May 2004
- "Women's Bodies, Women's Wisdom"; Christine Northrup; May 2010
