PCOS and fertility – Dr. Jessica Farren


PCOS is a common conditions that may influence fertility, approximately 1 in every 10 women is affected by PCOS.  Often it doesn’t cause any problems, but we explain in more detail below its impact and how it can be managed. 

What is Polycystic Ovarian Syndrome?

‘Polycystic ovaries’ is simply a way of describing what your ovaries look like on an ultrasound scan. Ovaries should have little cysts (collections of fluid – more properly referred to as ‘follicles’) on them – from which eggs are ultimately released – and ovaries appearing ‘polycystic’ just means that they have a few more of these little cysts (and are therefore overall usually a little larger) than average. Most women who have polycystic ovaries do not have polycystic ovarian syndrome (PCOS).

However, the appearance of PCO on scan has been associated with hormonal imbalance, in which there is relatively more of the hormone testosterone (this is generally thought of as the male hormone, but actually women need some of it too – just not too much), and a lack of response to insulin (the hormone that deals with sugar in the blood – and a lack of it can cause diabetes) – which overall can lead to a combination of symptoms – a ‘syndrome’.

A group of experts got together a few years ago to agree some criteria for a PCOS diagnosis. These are called the ‘Rotterdam criteria’ and they require someone to have at least two out of three of the following:

  1. Polycystic ovaries on scan
  2. Infrequent or absent ovulation – which usually means irregular periods (if you are not on the pill)
  3. Signs of high testosterone (usually bad skin (acne) or excess hair growth), or high levels of testosterone on blood tests

So, confusingly, this means that you can be diagnosed with PCOS even if you don’t have polycystic ovaries!!

It often runs in families – so women with the condition will often report their mother or sisters having similar symptoms, or a family history of diabetes.

PCOS and fertility

One of the features of PCOS is not ovulating regularly, meaning it can take longer to get pregnant. If time is on your side, you are still having periods most months (having a period is usually a sign that you’ve ovulated), and you’re happy to accept that it may take a little longer, then there’s no reason to do anything. Often maintaining a healthy lifestyle, with a good diet and regular exercise, and keeping your weight within the recommended range, will improve your fertility. However, if your periods are very infrequent, or you are above the age of 35, then you might want to consider discussing it further with your GP – and consider referral to fertility services – sooner than the standard recommendation (of one or two years of trying).

Fertility services (once they have done a thorough check to confirm that this is the only reason why you are not conceiving – i.e. a check of your womb and fallopian tubes, and also your partner’s sperm count) can prescribe medication to help you ovulate regularly (usually a medication called clomiphene). You can only be on this for a limited amount of time, and you need to have regular checks to make sure it is working and you are on the right dose. It does increase your risk of a twin pregnancy.

If ovulation induction isn’t successful, sometimes a procedure called ‘laparoscopic ovarian drilling’ is considered – in which a keyhole procedure is performed while you are asleep, and small holes are made in the ovary (it’s not known exactly how or why this works – but there is good evidence for it!). IVF may also be appropriate.

PCOS and pregnancy

PCOS seems to be associated with a slightly higher risk of early miscarriage.

Women with PCOS may be more likely to develop diabetes in later pregnancy (gestational diabetes). Some units will advise that all women with a past diagnosis of PCOS have a test called a ‘glucose tolerance test’ in pregnancy (usually at about 6 months) to check for diabetes.

Other implications of PCOS

Women with PCOS are more likely to develop diabetes in later life. Keeping a healthy weight significantly reduces this risk. It has also been shown that women with PCOS are more at risk of cardiovascular disease (including heart attacks and strokes) – so need to keep a close eye on their lifestyle and blood pressure to reduce this risk.

In PCOS, the lining of the womb (the endometrium) may be thickening under the influence of high levels of the hormone oestrogen, but, because of a lack of regular ovulation, is not being shed. A very thick endometrium is more prone to develop abnormalities in its cells, which can, if untreated, lead to endometrial cancer in later life. For this reason, women with PCOS and infrequent periods are advised to take medication (usually progesterone) to induce a bleed at least four times each year. Alternatively, women who do not wish to get pregnant might consider the intra-uterine system (IUS) called the Mirena coil ©.

Having PCOS seems to be associated with a higher risk of anxiety and depression. Some of this may be a reaction to the symptoms themselves, which can be understandably upsetting.