Exercising the embryo

Abstract

Lifestyle factors and choices are likely to emerge as the most interesting aetiological and confounding variables in the many causes of infertility and the success or failure of fertility treatment. The big three; obesity, cigarette smoking and recreational drugs are now joined by age especially of the woman, as the variables, which health care professionals struggle to influence. Helpful strategies for overweight women intending to conceive and achieve a sustainable normal weight exist but are undervalued or underutilised in favour of ‘quick-fix’ empirical fertility treatment rather than addressing obesity first. Kucuk and colleagues in this issue of Reproductive BioMedicine Online add further evidence of the beneficial effects of moderate levels of exercise for women undergoing assisted reproductive technology (ART), reporting substantially higher implantation and live birth rates than if there was a low level of exercise. Given that ART involves minor surgery for the oocyte retrieval, it is not a surprise that high levels of activity are not undertaken, but it is clear that immobilisation or reduced physical activity should not be advised. It is notable that the study groups here did not seem to include women at the extremes of BMI ranges, so one may speculate about how beneficial dietary advice for the underweight and dietary advice as well as exercise for the overweight might be. No doubt there are complex mechanisms involved, which are unlikely to be measurable using existing scientific tools, but this is no reason to doubt the findings in this well designed study. It is notable that none of the women undergoing ART had a high level of activity, so an enquiry about physical activity and reinforcing/advising women to maintain their normal moderate level of activity makes complete sense. Whether the benefits come from exercise induced factors acting directly on the implantation process or via complex neuroendocrine pathways is of secondary relevance, if any. As ‘research on the welfare of the human embryo’ is part of this journal’s mission statement we welcome studies such as Kucuk and colleagues have conducted. So if taking the embryo for regular walks or other forms of moderate exercise will lead to a higher chance of live birth then women should be encouraged to do so, but tread (mill) moderately.