It may be time to break out those walking shoes!
A new study has found that walking may increase the likelihood of conception for women with a history of pregnancy loss, especially for women who are overweight or obese.
Recent graduate Lindsey Russo teamed up with her advisor Brian Whitcomb, associate professor of biostatistics and epidemiology in the School of Public Health and Health Sciences at the University of Massachusetts Amherst, to analyse data from 1,214 healthy women aged 18 to 40 who had experienced one or two pregnancy losses.
Russo explained their results to Science Daily, saying:
"One of our main findings is that there was no overall relationship between most types of physical activity and the likelihood of becoming pregnant for women who had already had one or two pregnancy losses, except for walking, which was associated with higher likelihood of becoming pregnant among women who were overweight or obese."
Whitcomb says that their findings, which came from analysing results from the multi-site Effects of Aspirin in Gestation and Reproduction (EAGeR) study, show how our behaviours can impact our health:
"Lifestyle is definitely relevant to these outcomes because it can have an effect at the molecular level. What we eat and what we do are potential factors we can change to shape our health. So this sort of research is important because it helps provide information on the things people can actually do something about."
The Human Reproduction-published study found that the association between walking and the ability to conceive varied significantly depending on the woman's body mass index.
For women who were overweight or obese, walking for at least 10 minutes at a time was associated with a higher chance of falling pregnant.
As well, women who reported over four hours of vigorous activity each week were significantly more likely to conceive than their counterparts who did not undergo vigorous activity.
Moderate activity and sitting were not associated with a higher likelihood of becoming pregnant, however.
Speaking about this difference between the pregnancy odds for vigorous and moderate activity, Whitcomb noted:
"We don't know what to make of the finding that high-intensity physical activity may have different biological effects than walking, but our study doesn't offer enough detail to get at why vigorous activity would work differently than other levels."
The researchers say that physically active women may engage in certain behaviours that could explain this difference in likelihood to fall pregnant. They also caution that the study may not be representative of the general population.
Whitcomb added, "We were happy to be able to add scientific evidence to general recommendations about physical activity. This is especially true for the results about walking for even limited blocks of time. Walking has great potential as a lifestyle change because of its low cost and availability."
The team says that further research is needed to explore the mechanisms through which walking and vigorous activity may impact pregnancy odds.