Hirsutism (Excess Hair Growth)

Hirsutism is the growth of coarse, dark hair in women in a pattern more typical of men, such as on the face, chest, and back. It usually reflects the effect of androgens, the so-called male hormones that women also produce in small amounts. It is often linked to common hormonal conditions and is evaluated with a history, examination, and sometimes blood tests.

What hirsutism is

Both men and women produce androgens such as testosterone, but in different amounts. Androgens influence where and how coarse body hair grows, gradually turning fine, pale hair into the thicker, darker type known as terminal hair in androgen-sensitive areas. Hirsutism describes the appearance of this coarse, dark hair in places where women typically have little, including the upper lip, chin, jaw, chest, abdomen, lower back, and inner thighs. It differs from generalised increased fine hair over the whole body, which is a separate phenomenon with different causes.

The change can come from higher androgen levels in the blood, from hair follicles that are more sensitive to normal androgen levels, or a combination of both. Because hair patterns vary considerably with family background and ethnicity, what counts as excess is judged in context rather than against a single standard. The key feature is a shift toward a coarser, more male-pattern distribution, which a clinician assesses alongside other signs and the person's own sense of change over time.

Common signs and symptoms

The main feature is unwanted coarse hair, but hirsutism can occur with other signs of androgen activity. These may include:

• Coarse, dark hair on the face, chest, abdomen, lower back, or inner thighs
• Acne or oily skin
• Irregular or absent menstrual periods
• Thinning of scalp hair in a male-like pattern, particularly at the crown or hairline
• Difficulty with weight, which may accompany some underlying conditions
• In stronger forms, a deeper voice, increased muscle bulk, or other more marked changes (together sometimes called virilisation)

Hair changes that come on quickly, or are accompanied by rapid or marked signs of androgen excess such as voice deepening, usually prompt closer evaluation, since they are less typical of the common, gradual forms and occasionally signal a less common cause.

What causes it

The most common reason for hirsutism is polycystic ovary syndrome, a hormonal condition often linked to irregular periods, signs of androgen excess, and difficulty with weight. In many other people, no specific hormonal abnormality is found and the follicles are simply more responsive to normal androgen levels, a pattern sometimes called idiopathic hirsutism, which tends to run in families and to develop gradually.

Less commonly, hirsutism reflects other conditions. These include certain adrenal disorders that increase androgen production, raised levels of the hormone prolactin, thyroid problems, and, rarely, hormone-producing tumours of the ovaries or adrenal glands. Some medicines can also contribute. A clinician weighs the speed of onset, the severity, the menstrual history, and the overall picture to judge which causes are likely and which tests are worthwhile.

How it is diagnosed

Evaluation usually begins with a history that covers the menstrual cycle, the speed of changes, family background, and medicines, along with an examination of the hair pattern and other signs of androgen activity. Clinicians sometimes use a standardised visual scoring of hair in several body areas to gauge the extent. Depending on the findings, a clinician may order tests such as:

• Testosterone — to assess overall androgen levels.
• Other androgens — additional adrenal androgens may be measured in some situations to locate the source.
• Prolactin — since raised prolactin can be relevant to menstrual changes and hair growth.
• Thyroid tests — to check thyroid function, which can influence the menstrual cycle and skin.
• Tests related to PCOS — including assessments a clinician may use when that condition is suspected, sometimes with a pelvic ultrasound.

The table below outlines, in broad terms, how the common patterns tend to differ. It is illustrative only, and interpretation depends on the full clinical picture.

For background on the markers themselves, see our blood tests and hormones sections, our symptoms overview, and the conditions index for related topics.

How it is generally managed

Management depends on the cause, the degree of hair growth, and personal preferences, and it is decided with a clinician. When an underlying condition such as PCOS is present, addressing it is central and may help several symptoms at once. Approaches often combine measures aimed at the hormonal drivers with cosmetic methods of hair removal, and the right mix is individualised to each person's goals and circumstances.

Because hair grows in cycles and slowly, any approach generally takes several months to show a clear effect, and patience is part of the plan. Cosmetic options range from temporary removal to longer-lasting methods, and a clinician can help weigh them. General treatment principles are outlined in our treatments section. This page is educational and is not a substitute for personalised medical advice.

Complications and when to seek care

Hirsutism is rarely dangerous in itself, but it can cause significant distress, and the conditions behind it sometimes carry their own health considerations that are worth identifying. It is reasonable to seek assessment when excess hair is bothersome, when periods are irregular, or when hair growth appears alongside acne or weight changes. Prompt evaluation is sensible when hair growth is rapid or accompanied by deepening of the voice or other marked changes, so that less common causes can be considered.

Living with hirsutism

Living with hirsutism is as much about the emotional impact as the physical signs, and that impact is legitimate. Many people find that a combination of medical assessment, realistic expectations about timelines, and a chosen approach to hair removal helps them feel more in control. Day-to-day routines for managing hair can be time-consuming, and it is reasonable to seek practical advice on the options as well as on the underlying hormonal picture. Where a condition such as PCOS is involved, attention to overall health often supports several goals at once. Concerns about appearance, mood, and confidence are worth raising openly with a clinician, who can also point toward further support when the emotional toll is significant.