Pregnancy is one of the most common causes of female facial hair growth. As a fetus grows and matures in the body, a mother’s hormones begin to change in response to what is needed for development and growth to continue.
Androgen hormones are one type that can be affected during pregnancy. As androgens increase, secondary side effects of their presence such as dark hair growth on the upper lip and chin, can occur.
Certain hormone medications can also cause problems with female facial hair growth. For example, norgestrel, which is found in some oral contraceptives may increase androgen levels in the body, resulting in facial hair growth. Other medications that can cause this to occur include steroid medications, including the corticosteroid prednisone.
Genetics can also play a role in facial hair growth. Your genes determine how sensitive your skin and hair follicles are to androgen hormones in your body. If past female family members have had problems with facial hair, there is an increased chance that you may as well have problems with facial hair.
Disease or disorders of the ovaries and adrenal glands can also cause abnormal facial hair growth. The most common of these is Polycystic ovarian syndrome (PCOS), according to the American Society for Reproductive Medicine.
During PCOS the ovaries produce excess amounts of androgens, resulting in facial and body hair growth. Other disorders and diseases that could cause facial hair growth include tumors of the ovaries or adrenal glands, Cushing’s disease and onset adrenal hyperplasia.
Menopause may also increase androgen presence in the body resulting in facial hair growth. This occurs as estrogen production decreases, and testosterone production from the ovaries or adrenal glands increase. Hormone therapy can restore balances back to normal, but comes with varying side effects such as breast soreness and nausea.