Hair and Skin Problems
The skin manifestations associated with PCOS are possibly more common than either menstrual cycle irregularity, or obesity. Disorders of the skin in PCOS patients are related to an increase in level of male hormones (hyperandrogenism). This may be due to an absolute increase in androgen level, or an alteration in ratio of hormone levels. A third possibility is an exaggerated response of the skin to relative normal androgen levels. The end result of all three of these possibilities is the same and includes: acne, seborrhea, balding, hidradenitis suppurtiva (inflammation of the specialized sweat glands in the arm pit and groin), acanthosis nigricans (see below) and hirsutism.

Hirsutism is defined as an increase in amount and/or coarseness of hair distributed in the male pattern in a female. This is opposed to hypertrichosis which is excessive growth of non-sexual hair. The issue of facial hair is usually self-evident, but a good screening test is the amount of hair between the umbilicus and pubic hair line. Other areas of male pattern hair growth include 'sideburns,' lower neck, lower back and inner thighs. A faint moustache is quite common and may be more related to family trait and ethnic group than hormonal imbalance. The same can be said for occasional "stray" hair around the breasts. Outside hirsutism, other manifestations of hyperandrogenism are often dismissed, or not recorded in the gynecologist's evaluation.

Acne and seborrhea occur quickly as androgens rise. Androgens increase sebum which is a combination of skin oils and old skin tissue. Increased sebum causes plugging of skin pores. Bacteria that thrive on sebum are increased, resulting in inflammation. The inflamed skin pore is called a comedon. Closed comedones are "whiteheads," while "blackheads" are open comedones. The black color comes not from dirt, but from the breakdown of keratin, a natural skin product. Increased male hormone levels also cause seborrhea. A particularly common skin condition and one not usually associated with hormonal alterations is dandruff. Contrary to what is generally believed, dandruff is caused by oily, not dry skin and is a variety of seborrheic dermitis.

Many women complain of skin problems that wax and wane during the menstrual cycle. In regularly cycling women, the second half of the menstrual cycle is characterized by increased progesterone levels. Progesterone is a weak androgen and may create a situation of relative hyperandrogenism. Around the time of menstruation estradiol is decreased. Low levels of estrogen (hypoestrogenism) also creates a situation of relative increase in androgens with resultant increased oiliness and inflammation of the skin. One of the most distressing of hyperandrogenic skin disorders is alopecia (balding). The most androgen sensitive area of the scalp is the vertex, the highest point of the head. Frontal balding and anterior hairline recession is seen only in the more severe cases of androgen excess. As can be imagined, the mechanism for hair growth (and loss) has been extensively studied, but no unified theory has emerged.

A search for acanthosis nigricans (AN) should be a part of every physical exam of the PCOS patient. AN is usually described as a velvety, raised, pigmented skin changes, most often seen on the back of the neck, axillae and beneath the breasts. AN is often seen in association with skin tags (acrochordons). Possibly the best description is that it looks like the affected area is 'dirty' and would benefit from scrubbing. Obviously this is not the case. There is an association of this finding with simple obesity as well as other endocrine disorders. AN should always alert the clinician to a risk of diabetes, major lipid abnormalities, and hypertension. Although less common, it may be a warning signal of cancer.

Elevated androgen levels may be only a part of the problem. For androgens to have an effect on the skin they must bind together with an androgen receptor in the skin. There may little, or no, physical evidence of hyperandrogenism despite very high androgen levels, if the androgen receptor is lacking or present in relatively low numbers. The number of androgen receptors varies among different ethnic groups and individuals. Northern European women with PCOS are more likely to be hairier than Asian women. A third requirement for androgen action in the skin, besides androgens and receptors, is a specific enzyme called 5-alpha-reductase. Testosterone must be converted to dihydrotestosterone (DHT) by this enzyme to exert its effect. Only sexual hair follicles contain the necessary enzymatic machinery for conversion of circulating androgens to DHT. A fair skinned individual may have little excess hair growth despite high levels of testosterone, due to absence of the specific androgen receptor, or enzyme converting capacity, in the hair follicles. Another individual may be quite hirsute with no apparent abnormality in circulating hormones.