Polycystic Ovary Syndrome (PCOS)

Definition

Polycystic Ovarian Syndrome (PCOS) is arguably the most common cause of infertility in women. The classic syndrome was originally described in 1935 by Stein and Levanthal, and featured hyperandrogenism (high levels of male hormones circulating in the blood stream), irregular periods, polycystic ovaries as will be described below and excess weight gain around the waist (central adiposity). PCOS is a syndrome and is not a disease, and there are multiple potential causes. In the picture below, it can be seen that the ultrasound appearance of polycystic ovaries (PCO) is enlarged ovaries that have multiple very small "cysts" just inside the outer margin (capsule) of the ovary.

There is international consensus that on its own the ultrasound appearance of PCO is not enough to make the diagnosis of polycystic ovarian syndrome (PCOS). Furthermore, the ultrasound appearances of polycystic ovaries are present in approximately 20% of normal women. Consequently, it is important to understand the difference between PCO and PCOS.

PCOS is diagnosed if a woman presents with any two of the following three features; infrequent or absent ovulation, physical signs or blood tests consistent with high levels of male hormones (hyperandrogenism) and the ultrasound appearances of polycystic ovaries. Furthermore, there should not be any other hormonal cause(s) of this situation.

Causes of PCOS

The most recent thought about how PCOS develops is that the body has become resistant to the hormone insulin, which normally regulates sugar levels in the blood stream. More insulin is produced in order to compensate for this, and through a number of hormonal mechanisms the resultant high levels of insulin lead to the ovaries producing more testosterone (male hormone) and numerous small follicles that have failed to develop properly (atretic). This process leads to the characteristic appearance of polycystic ovaries as will be described below. Other factors have been implicated in the development of PCOS such as a "hormone" called ghrelin that is produced in the stomach.

Women who have PCOS have enlarged ovaries with a smooth-thickened outer layer (capsule). Just below the capsule there are numerous follicles at various stages of failed development (atresia) in the outer (peripheral) part of the ovary. This gives rise to an appearance on ultrasound examination as in the picture above that has been described as being similar to a "pearl necklace".

Symptoms of PCOS

The commonest presentations are infertility, being overweight (with more weight gain in the waist than the hips), having signs of high testosterone (male hormone) levels including acne, unwanted hair growth (hirsutism) male pattern baldness, brown or black pigmentation of the skin in the neck, armpits, or under the breast, or irregular periods. Whilst many women with PCOS can be overweight, some are thin (lean). Some women who have PCOS do not have any symptoms.

Investigations

Investigations that can be performed for PCOS include a pelvic ultrasound examination, blood levels of hormones such as testosterone, and investigations of sugar levels in the blood stream such as a glucose tolerance test (normally undertaken to screen for diabetes). If the blood sugar levels are high, it is important to bring these under control before trying for a pregnancy in order to prevent complications for the baby or mother that can be associated with such high sugar levels. Some women with PCOS have high blood lipid levels.

If the testosterone or other male hormone levels are found to be high, it is important to exclude other sources of these high levels such as some medications or increased hormone production coming from the adrenal gland or ovary. In order to achieve this more hormone testing may be required. Blood levels of these male hormone tests can sometimes be unreliable, and women may be found to have a high level on some occasions and normal levels on other occasions. This can lead to confusion about whether a woman has PCOS and a level of frustration when a clear answer (diagnosis) hasn't been given. However, it can be important to take time to make the diagnosis as women with PCOS are more likely to develop sugar diabetes or high levels of blood lipids later in life, and so with a firm diagnosis appropriate long-term health screening can be put in place together with lifestyle adjustments such as weight loss.

If a woman's menstrual cycle is irregular, other hormonal causes should be excluded such as conditions of the thyroid or pituitary glands. Women who have PCOS and have infrequent periods sometimes develop a condition of the lining of the uterus (endometrium) called hyperplasia. Endometrial hyperplasia can be detected by taking a sample of the uterine lining. This can often be performed in the office by doing an endometrial biopsy (similar to having a PAP smear). When a woman with PCOS has completed her fertility care, it is important to discuss long term approaches to the prevention of endometrial hyperplasia with her specialist and general practitioner, as if present and left untreated this condition could ultimately turn into a form of uterine cancer.

Treatment

For women who have infertility associated with PCOS, there are a number of possible treatments. These include different types of medication and a surgical approach to treating PCOS called laparoscopic ovarian diathermy. In-vitro fertilization (IVF) can be a very effective treatment, but is often used after more simple approaches have been tried. In some circumstances where there are other infertility factors such as in older women, women with blocked or damaged fallopian tubes or where there is a male factor problem, IVF may be the best first line treatment. Women who have PCOS are more likely to develop a complication of IVF called ovarian hyperstimulation syndrome (OHSS). Your Fertility Specialist will be aware of this, and will monitor you carefully and manage your treatment in ways that can reduce the risk of this complication occurring.

Where tests of blood sugar levels show that treatment is required to bring those sugar levels under control, it is important to do so before trying to achieve a pregnancy. Achieving good blood sugar levels will reduce a number of risks for you and your baby that are associated with high blood sugar levels both before and during pregnancy. Therefore, the relatively short delay in starting infertility treatment associated with first controlling blood sugar levels is well worth the time spent.

Endometrial hyperplasia as described above, requires treatment (often by using hormonal preparations for a number of months such a progesterone-like medication), in order to prevent the hyperplasia from developing into more serious abnormalities that if left untreated could ultimately develop into a cancer of the endometrium. Women who have PCOS and have infrequent periods can also be put onto medication to ensure that they have regular periods, and so minimise the risk of hyperplasia developing.

Lifestyle Changes

For women who have PCOS and are overweight, lifestyle changes can be very important in helping to control symptoms and also in improving the chance of success of different treatments. Even small changes can make a big difference. For example, a weight loss of only 5% of total body weight can be associated with decreased insulin levels, improved menstrual function, reduced growth of unwanted hair, less acne and lower testosterone levels. Therefore, achieving small steps (goals) can be extremely important, and so it is important not to become despondent with slow progress.

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