Polycystic Ovary Syndrome (PCOS) is the most common endocrinopathy affecting reproductive-aged women with a prevalence of 8–13%. It is characterized by ovulatory dysfunction and causes menstrual dysfunction, hyperandrogenism and polycystic ovaries.
Two out of three of the following criteria are required to make the diagnosis:
PCOS is an extremely heterogenetic and complex disease. PCOS may be related to many different factors working together. These are insulin resistance, increased levels of hormones called androgens and an irregular menstrual cycle.
The typical polycystic appearance of the ovaries is seen on a transvaginal ultrasound in the majority of women with irregular menses and hyperandrogenism. However, this ultrasound appearance is not specific, it may be seen in women with regular menstruation. Ultrasound criteria include the presence of 12 or more follicle in each ovary measuring 2 to 9 mm in diameter or increased ovarian volume(>10ml). For many women, diagnosis of ovarian cysts raises a concern about tumours but they are numerous small eggs that are not ovulating.
Women with PCOS show menstrual irregularities that range from oligomenorrhea and amenorrhea to very heavy, irregular periods. The menstrual irregularity typically begins in the peripubertal period and menarche may be delayed. After age 40 years, women with PCOS often have regular cycles.
Acne, hirsutism and male pattern hair loss are clinical signs. Elevated serum androgen concentrations are found. Hirsutism is excessive hair growth in male distribution (upper lip, chin, periareolar area, mid sternum, along the linea alba of the lower abdomen)
40 to 85 per cent of women with PCOS are overweight. There is a high prevalence of insulin resistance.