Women with obesity seeking IVF found to be 47% more likely to conceive naturally after weight loss

The University of Oxford-led research, funded by the National Institute for Health and Care Research, analysed 12 international trials involving 1,921 women. Beyond the increase in natural conception, the study found weight loss interventions increased the odds of any pregnancy (naturally or by IVF) by 21%.

The findings, published in the Annals of Internal Medicine, are particularly significant as NHS commissioning bodies across England restrict access to NHS-funded IVF for women with a Body Mass Index (BMI) over 30. The study suggests that providing structured weight loss support could not only help women become eligible for NHS-funded treatment but may also increase their chances of conceiving without medical assistance.

Dr Moscho Michalopoulou, lead author from Oxford’s Nuffield Department of Primary Care Health Sciences, said: 'Currently, women with obesity can face a double challenge with higher rates of infertility and potential exclusion from NHS-funded IVF. Our findings offer hope. They suggest that offering structured weight loss support could improve the chance of conceiving naturally, which may avoid the need for IVF treatment. Programmes that help women achieve greater weight losses have the potential to help more women achieve a successful outcome, and should be tested in larger high-quality trials.'

The review synthesised evidence from a wide range of interventions, including diet programmes, exercise, and weight loss medications such as orlistat (which reduces fat absorption) and older GLP-1 agonists - earlier versions of the drug class that now includes Ozempic and Wegovy. On average, women in the intervention groups lost 4kg more than those in the comparison groups.

Read the full story on the University of Oxford website.