Scientific Advisory Committee Opinion Paper 17
The full SAC Opinion Paper can be downloaded below:
Guidelines from the National Institute for Health and Clinical Excellence recommend that women seeking fertility advice with a BMI above 29 kg/m2 should be informed that they will take longer to conceive, that assisted reproduction is less likely to be effective at this BMI and that losing weight in a structured group programme of exercise and dietary advice is likely to increase their chances of conceiving. Fertility specialists therefore face the challenge of deciding whether to employ a cut-off weight (or BMI) before fertility treatment is instigated, how prescriptive to make cut-off points and at which point in the process should such a cut-off point be employed. Consensus was reached in the British Fertility Society guidelines that fertility treatment should be deferred in women who are morbidly obese, until they have lost weight to below a BMI of 35 kg/m2, although in those with more time (under 37 years with normal ovarian reserve) a weight reduction to less than 30 kg/m2 is preferable. The US Agency for Healthcare Research and Quality has issued a technology assessment on weight-loss surgery and pregnancy, commissioned by the American College of Obstetricians and Gynecologists. This assessment suggests that women who are obese increased their chances of getting pregnant and reduced their risk of pregnancy complications by having bariatric surgery and that outcomes after delivery for both mother and child were acceptable, provided that adequate nutrition and vitamin supplementation was maintained. If these women are indeed healthier than their absolute BMI suggests, caution should be exercised when determining eligibility for in vitro fertilisation in women who have undergone bariatric surgery.
