Weight loss surgery can improve fertility and reproductive outcomes in obese women, according to the Royal College of Obstetricians and Gynaecologists.
However, it should be considered a “last resort” in obese women attempting to conceive, said the RCOG in its latest scientific impact paper (see attached PDF, below-right).
“Weight loss surgery can improve fertility and reproductive outcomes in obese women”
It reviewed the latest evidence around the safety and effectiveness of different types of bariatric surgery as an intervention to improve fertility and reproductive outcomes in obese women.
Bariatric surgery results in a 15-25% long-term loss of body weight, as well as significant reductions in illnesses associated with obesity, such as diabetes, high blood pressure and certain cancers.
The authors agreed that the only effective ways of inducing long-term weight reduction in women with severe obesity were either significant sustained lifestyle changes or bariatric surgery.
However, they stressed that it would be impractical to recommend surgery to all obese women of reproductive age.
Professor Adam Balen, lead author of the paper and RCOG spokesman, said: “Our review of all the literature on this subject confirms that weight loss surgery can improve fertility and reproductive outcomes in obese women.
“But we believe it should only be considered as a last resort when other treatments, such as lifestyle changes, haven’t worked,” he said. “As with any major operation, bariatric surgery carries a risk of complications but also requires a significant change in lifestyle afterwards.
Professor Balen noted that, as well as surgery recovery time, it could delay conception by 12-18 months during the initial weight loss phase, because the foetus may be at risk of nutritional deficiencies.
“Before considering weight loss surgery, women planning a family who are overweight or obese should lose weight through a healthy, calorie-controlled diet and increased amounts of exercise,” he said, highlighting the free NHS weight-loss plan or referral to a weight loss support group.
In addition, the review looked at evidence showing that bariatric surgery improved signs and symptoms associated with polycystic ovary syndrome, which influences fertility, including anovulation, hormonal changes and libido.
Bariatric surgery was also associated with higher success rates of assisted conception, including IVF.
“As with any operation, bariatric surgery is associated with some risks and complications can include infection, protein malnutrition, deep vein thrombosis and hernia”
Current guidelines, published by the National Institute for Health and Care Excellence, recommend bariatric surgery only in cases where a patient has a BMI of 40 or above or a BMI of 35 or above and another serious health condition that could be improved with weight loss.
In both cases, surgery is only available on the NHS when other treatments, such as lifestyle changes, have not worked.
Dr Sadaf Ghaem-Maghami, chair of the RCOG’s scientific advisory committee, said: “As with any operation, bariatric surgery is associated with some risks and complications can include infection, protein malnutrition, deep vein thrombosis and hernia.
“An increased rate of small for gestational age babies and preterm birth has also been documented in some research,” she said.
Janet Fyle, professional policy advisor at the Royal College of Midwives, said: “Women will welcome this clear assessment of the scientific literature showing the having had bariatric surgery may improve a woman’s chances of becoming pregnant and reduce complications.
“A key point is that women should wait 12-18 months after surgery before becoming pregnant to avoid the risk of nutritional deficiencies,” she said.
“We cannot emphasise too strongly the need for women to start their pregnancy in optimal health”
However, Ms Fyle noted that, ideally, the focus should be on preventing obesity and reducing the need for surgery.
“We cannot emphasise too strongly the need for women to start their pregnancy in optimal health, at a healthy weight, and to maintain this during and after their pregnancy,” she said.
“There is a need for a greater priority to be placed on health promotion including better information, education and support for women and their families, about the benefits of healthy eating before and during pregnancy, and taking appropriate exercise,” she said, adding that more emphasis was also needed on pre-conception care.
Ms Fyle added: “We cannot talk about this issue outside of the context of poverty and inequality.
“This is also about reaching out to those groups in society who need the greatest help and support to not only eat healthily, but also have a generally healthier lifestyle.