Lifestyle intervention ‘can improve pregnancy chances’
Women with a high BMI stand an improved chance of falling pregnant naturally if they undergo a ‘lifestyle intervention’ before conception, new analysis suggests.
Several studies have already noted that overweight or obese women are at an increased risk of infertility, and potentially less likely than women of a normal weight to conceive, even after fertility treatment.
Earlier this year, a major Dutch trial established that weight loss intervention before fertility treatment had no noticeable effect on the number of women for whom treatment was successful.
In terms of natural conception, however, the rate of pregnancy was found to be significantly improved in those who received the lifestyle intervention.
At the European Society of Human Reproduction and Embryology’s Annual Meeting in Helsinki, Dr Anne van Oers of the University Medical Centre in Groningen presented the latest findings from a sub-analysis of existing LIFEstyle data.
It confirms that the chance of delivery from fertility treatment will not be improved by weight loss. However, the rate of natural conception was indeed enhanced by preconceptional lifestyle changes.
The women who were observed over the 24-month study period were split into six sub-categories, which were defined by age (under or over 36 years old), body weight (below or over a 35kg/m2 BMI), and cycle regularity (ovulatory or anovulatory).
Regardless of their subgroup, women having fertility treatment experienced no reportable fluctuations in the healthy live birth rate or overall live birth rate, despite the changes to their lifestyle.
But a significantly beneficial effect from the intervention was seen across most subgroups of women able to conceive naturally. This was particularly the case with those in the anovulatory group.
In fact, the most striking figure was that between anovulatory and ovulatory women. Despite both groups receiving the same lifestyle intervention, the latter group had a natural conception rate of 11.4%, compared to 28.6% for the former.
Speaking on the results, Dr van Oers reported: “Our finding that lifestyle intervention in obese women more often leads to natural conception, specifically in anovulatory women, should be used in their counselling before fertility treatment and could reasonably be offered as first-line treatment for anovulation in obese women."
Dr Hoek said that only 78% of the women with obesity and infertility were able to adhere to the weight loss programme, and that their chances of getting pregnant turned out exactly the same as for those who started fertility treatment immediately.
"Despite intensive coaching," said Dr Hoek, "22% of the women were unable to maintain the six-month lifestyle programme, and they had a significantly lower chance of getting pregnant. And those who did complete the programme had a greater chance of getting pregnant naturally than the women who started fertility treatment immediately."