B11. Hyperandrogenic disorders, PCOS

Page created on June 7, 2021. Last updated on March 23, 2024 at 15:43


Hyperandrogenism in females is defined as a state of excess androgen levels which cause symptoms such as hirsutism, acne, excessive hair growth, and male-pattern hair loss. PCOS accounts for 80% of causes, but other causes include:

  • Non-classic CAH
  • Cushing disease
  • Hypothyroidism
  • Hyperprolactinaemia
  • Androgen-secreting tumour

Women with excessive hair growth often shave their facial hair, so it might be difficult to evaluate. However, hair on the chest and fingers grows only in the case of hyperandrogenism and can be used to evaluate it.

Polycystic ovary syndrome (PCOS)

Definition and epidemiology

Polycystic ovary syndrome is characterised by oligomenorrhoea, hyperandrogenism, and anovulation. It’s a common disorder, as it affects approx. 10% of women. It’s the most common cause of hyperandrogenism in females.

Symptoms usually begin in adolescence.

Risk factors

  • Obesity
  • Diabetes mellitus
  • Family history


The pathomechanism is unknown. One hypothesis is that obesity leads to insulin resistance and hyperinsulinaemia, which increases the frequency of GnRH pulses from the hypothalamus, which stimulates LH more than FSH. This leads to increased androgen production and decreased follicular maturation in the ovaries. However, many PCOS patients are not overweight.

Another hypothesis is that the ovarian capsule is thickened, which prevents follicles from rupturing, causing follicles to accumulate and grow into cyst.

Clinical features

  • Oligomenorrhoea or amenorrhoea
  • Hyperandrogenism
    • Hirsutism
    • Acne
    • Male-pattern hair loss
  • Other symptoms
    • Overweight or obesity
    • Type 2 diabetes
    • Mood disorders

The chronic anovulation is a risk factor for endometrial hyperplasia and cancer.

Diagnosis and evaluation

We should test for biochemical evidence of hyperandrogenism, by measuring serum androgens. We can also measure an LH:FSH ratio of > 3:1.

Transvaginal ultrasound is essential to look for polycystic ovaries.

The diagnosis is made based on the Rotterdam criteria. According to these criteria, at least two of these three criteria must be present:

  • Oligo/anovulation
  • Hyperandrogenism (clinical or on labs)
  • Polycystic ovaries on ultrasound

After diagnosis, we should screen for diabetic, cardiovascular, and hepatic complications.

Differential diagnosis

It’s important to rule out other causes of oligomenorrhoea:

  • Physiological oligo-amenorrhoea in teenagers
  • Non-classic CAH – by measuring 17-hydroxyprogesterone
  • Pregnancy – by measuring hCG
  • Thyroid disease – by measuring TSH
  • Hyperprolactinaemia – by measuring prolactin


All overweight patient should undergo lifestyle changes to achieve weight loss and increase physical activity. These interventions improve both physical and psychiatric symptoms.

Combined oral contraceptive pills decrease the hyperandrogenism, restore normal menstrual cycles, and provide protection against endometrial cancer. If they’re not sufficient, we can add antiandrogens like spironolactone or cyproterone acetate.

Metformin is also commonly used. It restores normal menstrual cycles in 50% of women.

If weight loss is not sufficient to treat infertility in those with infertility who desire pregnancy, we should use drugs to induce ovulation.

4 thoughts on “B11. Hyperandrogenic disorders, PCOS”

  1. hypertrichosis should not be included here as it’s defined as excessive hair growth which is independent to androgen levels (i.e. it refers not only to excessive hair growth, but it’s a condition where this occurs independent to excess androgen levels)

      1. There are many sources which reference to it like this, and the pattern is distinguishable from the male-pattern hair growth seen with androgen-dependence (aka hirsutism). If you also look at the causes for hypertrichosis on uptodate, these are not related to androgen action.

        From uptodate:
        “Generalized hair growth — There are at least two forms of generalized hair growth that do not represent true hirsutism:
        ●Androgen-independent hair, which is the soft vellus unpigmented hair that covers the entire body. In infants, this hair is called lanugo.
        ●Hypertrichosis, which refers to diffusely increased total body hair growth. This is a rare condition that is usually caused by a drug, examples of which include phenytoin, penicillamine, diazoxide, minoxidil, and cyclosporine. Hypertrichosis also can occur in patients with some systemic illnesses, such as hypothyroidism, anorexia nervosa, malnutrition, porphyria, and dermatomyositis, and as a paraneoplastic syndrome in some patients. (See “Cutaneous manifestations of internal malignancy”, section on ‘Hypertrichosis lanuginosa’.)”

        From Statpearls:
        “Hypertrichosis is defined as excessive hair growth anywhere on the body in either males or females. It is important to distinguish hypertrichosis from hirsutism, which is a term reserved for females who grow an excessive amount of terminal hairs in androgen-dependent sites.”

        From Osmosis:
        “Hypertrichosis is a condition independent of androgen production, whereas hirsutism results in excess hair growth in androgen-dependent areas of the body, such as the chin, upper lip, chest, and back. Hirsutism specifically occurs in those assigned females at birth.”

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