Around one in ten women have polycystic (poly = many, cystic = cysts) ovaries. The ovary creates an egg by producing a little cyst (a follicle). The ovary produces the egg by bursting open the follicle. It gets the message to do this from a gland in the brain (the pituitary gland). If the ovary is not able to produce the egg by bursting the follicle, a number of unruptured follicles will stay in the ovary, giving the appearance of many little cysts (polycystic).
So this term describes the appearance of the ovaries when they are seen on an ultrasound scan. Polycystic Ovary Syndrome (PCOS) is the name given to a condition in which women with polycystic ovaries have one or more additional symptoms. So not all women with polycystic ovaries have PCOS, but all women with PCOS do have polycystic ovaries. There is a range of difficulty with ovulation, from the woman who doesn’t ovulate once or twice a year, to women who never produce an egg.
The diagnosis of PCOS is made by performing an ultrasound scan to look at the ovaries, and by performing a blood test to check on the hormones that control and are produced by the ovary. Polycystic ovaries contain many small cysts – at least ten. Some of these cysts contain eggs, some are no longer active, and others will not produce an egg but can still release hormones. The cysts are quite small, usually no bigger than 8 millimetres, but they are clear enough on ultrasound to allow accurate diagnosis. We do not know why women develop PCOS.
Symptoms of PCOS include:
- Infrequent periods: In normal circumstances, each month you build up the lining (the endometrium) of your womb (uterus). After producing an egg the lining is matured or ripened, in case a pregnancy occurs. If there is no pregnancy, the lining is shed (your period or menses) and you start the process all over again. If you do not ovulate regularly, you will not have a regular period. Infrequent ovulation or no ovulation at all (anovulation) will lead to infrequent (oligomenorrhoea) or no menstrual periods at all (amenorrhoea). Some women notice pelvic pain, which may be related to the effect of hormones on the flow of blood through the pelvic veins.
- Subfertility: If you don’t produce an egg, you can’t conceive. If you only produce eggs now and then, it will be very difficult to know when you are fertile. So women with irregular cycles hoping to get pregnant will have better chance one their monthly cycles have returned to normal.
- Miscarriage: The high levels of hormones (luteinising hormone, LH) from your pituitary gland (see above) that occur when your body is having to work extra hard to get you to produce an egg, increase your risk of miscarriage. If you suffer from infrequent periods and want to get pregnant, you should see your doctor for some tests before trying to get pregnant.
- Skin problems: When the eggs are not produced from the ovary, some of the unruptured follicles (eggs) release homones that can be converted by your body, typically in your fat (adipose tissue) into testosterone, the ‘male’ sex hormone which circulates in both men and women. Excessive testosterone levels in women may be a cause of acne on the face and back, or unwanted hair on the face, chest, arms and legs. The levels of testosterone in women with PCOS are still much lower than those found in men. If you are concerned you should see your doctor.
- Weight gain: Changes in weight often lead to infrequent periods. If you gain weight the ovary can have difficulty producing eggs (PCOS), and if you lose a lot of weight, your pituitary gland may stop trying to get you to produce eggs, leading to a loss of periods.