Even if irregular menstrual cycle surely does not sound too good and affects 30 % of the women during their reproductive cycle, a condition associated with this syndrome and named polycystic ovary syndrome (PCOS) is much more serious for a woman's health, from unaesthetic excess hair growth on their face, chest or abdomen to sterility, higher risk of heart disease and diabetes.

10 % of the women of reproductive age suffer of PCOS (thus one third of women with irregular menstrual cycles), thus this condition is the most common hormonal abnormality experienced by women during their reproductive years. "Women often notice that something is wrong when they have irregular bleeding - either infrequent and very light or more frequent and heavy - and often excess hair growth," says Dan Lebovic, assistant professor of obstetrics and gynecology at the University of Michigan Medical School. "If women are having irregular cycles, they should have their physician examine them either at their annual exam or sooner," said Lebovic.

Polycystic ovaries are caused by small cysts that appear on the inside of the ovary. "This makes the ovary appear more plump than usual during surgeries or on imaging studies and creates multiple blebs (blisters) on top of the ovary in such a way that the ovary looks like an inverted golf ball." said Lebovic.

Each cyst contains a small ovule that cannot be expelled due to the abnormal hormonal environment. This triggers irregular menstrual cycles, with 3-10 periods annually, without the use of any hormonal birth control pill. "The accompanying problems for women can be limited and mild, or broad-ranging and severe," Lebovic says.

Some patients have higher levels of LDL cholesterol (bad cholesterol), which rises the risk of developing heart disease. "Many PCOS patients experience fertility problems simply because they can't produce an egg for fertilization every month. They have an increased risk of diabetes, with about 30 % of PCOS patients suffering from pre-diabetes or insulin insensitivity and 10 % having type II diabetes," said Lebovic.

PCOS women are also exposed to endometrial cancer (on the lining of the uterus). "Researchers are investigating the causes of PCOS, which may be an underlying insulin disorder that leads to the ovarian cysts, or which may begin as an enzyme malfunction in the ovary that leads to problems with insulin processing," added Lebovic. "Sometimes the condition isn't discovered until a woman is having difficulty becoming pregnant", he says.

OPCS are treated with metformin, which drops the amount of excessive hair and can rise the ovulation rate. Women not willing to get pregnant are often treated with birth control pills.