It is unknown whether insulin resistance is a cause of PCOS or a symptom, but regardless one of the large contributing factors to my infertility due to PCOS is/was insulin resistance. When you have insulin resistance, the cells in the body are resistant to insulin, thus they don’t take up glucose from the blood easily; and the body increases the amount of insulin produced, to force the sugar into the cells . High insulin levels affect the ovaries and cause them to produce too much LH (Luteinising Hormone) which then disrupts the cycle and prevents ovulation . Thus in order to ovulate, your insulin levels have to be lowered and more regulated. There are a few ways in which to do this, you can change your diet (follow a low-carb/ketogenic diet) and/or you can take an insulin-sensitizer such a metformin. Sometimes your menstrual cycles will right themselves after some weight loss (about 5% of your body mass) or after being on the metformin for at least 6 months.
Clomiphene Citrate (Clomid) is often the first suggested therapy for anovulation (not ovulating like in PCOS). However many women are Clomiphene resistant (don’t ovulate no matter what the dose). In this case it is recommended that both Metformin and Clomiphene are taken, as the metformin can possibly reduce the clomiphene resistance .
In my case I had only been on a low dose of Metformin before I was put on 50mg of Clomid, and I didn’t ovulate. I then decided to give myself 6 months on a higher dose of Metformin (recommended level is over 1500mg/day, I use 2 x 850mg tablets per day) before trying another cycle of Clomid, and the next Clomid cycle I ovulated at 50mg! In total to conceive my son, I did 5 rounds of Clomid (all at 50mg) and got pregnant twice (one miscarriage and one live birth). I truly think I would be resistant to the Clomid if I didn’t take a high dose of Metformin.
Women with PCOS have an incredibly high early miscarriage rate (1st trimester) of between 30-50% (per pregnancy) versus 10-15% for non-PCOS women . Luckily you can take Metformin throughout your pregnancy and drop your chance of early miscarriage to the regular 10-15% as well as decreasing your chances of premature-birth [5, 6].
So after all the wonderful stuff Metformin can do for you why isn’t everyone taking it? Metformin can cause some unfortunate gastro-intestinal side effects (mostly diarrhoea). However by starting at a low dose and slowly increasing it or by using the extended-release version most people eventually tolerate it . In fact, according to , although about 25% of people will experience some GI issues until they get used to the drug, only 5% of people are completely unable to tolerate metformin.
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