Hirsutism (or hypertrichosis) is the medical term for the presence of excess body hair in both sexes, and facial hair in women.
There are obvious racial and family reasons for a hairy body, with some races and families carrying genes that predispose to the growth of hair on the chest, belly, back, buttocks, arms and legs. Facial hair in men also varies between races, with southern Asians having a scanty beard, while northern Europeans can grow a thick bushy beard.
Hair is normally present on all areas of skin except the palms and soles. Hirsutism is often the presence of coarse dark coloured hair rather than fine body coloured hair.
At puberty, both sexes develop hair on the lower abdomen above the genitals and in the armpits, but sometimes excessive hair growth may occur in other areas, including the face of girls. This problem usually settles down over a few years as the hormone levels stabilise.
The menopause, and associated hormonal changes, may see the growth of hair on the face and chest of women.
Women whose periods cease for no apparent reason may be suffering from a hormonal imbalance that results in hirsutism. Other women naturally have a hormonal makeup that allows normal menstrual periods and fertility, but still inappropriately stimulates body and facial hair growth.
Other causes of hirsutism include tumours and diseases of the pituitary gland in the brain, tumours or injury of the testes or ovaries, failure of the thyroid gland in the neck to produce sufficient thyroxine (hypothyroidism), starvation, severe psychological stress (may affect hormone production), the Stein-Leventhal syndrome (causes multiple cysts in the ovaries to affect their function), Cushing syndrome (over production, or excessive use of cortisone), Achard-Thiers syndrome (postmenopausal women with diabetes) and foetal alcohol syndrome (babies born to alcoholic mothers).
Numerous medications, including cortisone, oral contraceptive pills, minoxidil, diazoxide, streptomycin, muscle building anabolic steroids, phenytoin and metoclopramide, may have hirsutism as a side effect.
Anyone with hirsutism for no obvious cause should have the condition investigated. Most forms can be successfully treated by dealing with the cause, or using medications that reduce the growth of body hair (eg. spironolactone, antiandrogens). Individual hair electrolysis permanently removes that particular hair.