In this study, the investigators wish to investigate how pioglitazone treatment effects hirsute women. Hirsute women are often overweight and have an increased amount of male sex hormone in their blood. Their blood tests show frequent changes corresponding to the changes seen in diabetic patients.

Pioglitazone is a drug used for increasing the insulin sensitivity in diabetic patients. Previous studies showed that this drug is able to decrease the level of insulin in blood in hirsute women. Moreover, the level of male sex hormones is reduced during this treatment. The drug has only been marketed for few years, and no investigations have been carried out as to the reaction of other hormones, e.g. growth hormone and stress hormone, using this treatment.

This clinical trial includes 30 strongly hirsute women. The patients are randomized to either placebo or an active drug. The treatment period is 16 weeks. The patients included must be healthy and take no medicine possibly changing the results of the study. The patients must take no contraceptive pills or receive any other hormone treatment.

In connection with the investigation, the following will be carried out on all patients: glucose tolerance test, clinical examination, blood tests, measurement of stress hormones and sex hormones, hyperinsulinaemic euglycaemic clamp test, muscle biopsies and bone scan.

This examination programme will be carried out before start of pioglitazone or placebo treatment and again after 16 weeks of treatment. The examinations require 2½ days of hospitalization.

The purpose of the study is to gain more knowledge of the reasons for hirsute women to grow more hair than normal women. The study will show whether pioglitazone treatment can reduce the amount of male sex hormone in blood and how the level of stress hormone and growth hormone is changed when reducing the amount of insulin in blood.

Inclusion Criteria:

• Irregular menses, i.e. cyclus length of >36 days
• Premenopausal
• Increased fasting insulin > 50 pmol/l
• Increased free testosterone > 0.035 nmol/l

Exclusion Criteria:

• Age: <18 years
• Contraceptive pill within the past 3 months
• Postmenopausal (increased FSH)
• Known diabetes mellitus, endocrine disease or other disease requiring treatment
• Drug use
• Pregnancy
• Planned pregnancy during the treatment period
• Increased liver parameters