Why weight matters for IVF

12th October 2011 in IVF

A new study has confirmed that your weight can affect whether IVF treatment is successful or not.

A team from Guy’s and St Thomas’ NHS Foundation Trust  found that being even slightly overweight is a risk factor for the outcome of IVF, following their study of more than 400 women undergoing treatment at the Assisted Conception Unit.

In the study, the team looked at patients’ Body Mass Index (BMI) and results of treatment. The chance of having a live birth for women who are classed as ‘overweight’ is reduced by as much as nine percent, whilst the risk of miscarriage is 24 per cent higher. For women classed as ‘obese’ the risk is even higher, with the miscarriage risk increasing by as much as 40 per cent, and the chance of a live birth dropping by 20 per cent.

Previous studies have also shown that obesity affects both natural conception and pregnancy, as well as IVF. What this shows us however is that even being overweight by perhaps only a small amount, such as a couple of stone, does affect IVF. The higher your BMI, the lower the chance of a successful outcome.

So the advice is, quite rightly, to make sure that both you and your partner are in the best health you can be before you embark on any infertility treatment. This could be particularly important if you are an older woman, over the age of 37, looking to have IVF treatment. Success rates in older women are already reduced due age and egg quality, so being overweight may reduce them further.