A U study found that high temperatures and low precipitation rates can cause lower birth weights.
Conducted over the course of two years, the study focused on the climates of 19 African countries over a 25-year period. Researchers used a combined method of data from multiple sources. Because the information was so expansive, analysis was difficult, and climatologists were consulted to determine how rainfall and temperature should be thought about in the context of the study.
To account for genetic factors, analysts compared the birth weights of siblings. If one sibling was of a healthy birth weight and another was abnormally lower, environmental factors would be considered to play a key role.
Heidi Hanson, research assistant professor, said this was a “robust way of looking at the same factors.”
The findings showed that high temperature has a larger effect on birth weight than low precipitation does, but both contribute to infants born underweight. These elements were prevalent to the data, as the countries examined have little access to air conditioning and clean water.
Kathryn Grace, an assistant professor in the department of geography and the lead author of the study, views pregnant women in developing countries as especially susceptible to these factors.
“I think one of the important parts of this project is that we identified that things like heat are going to be difficult for pregnant women to deal with,” she said. “We don’t often evaluate the specific kinds of exposure.”
As there is little that can be done to help pregnant women in developing countries avoid the heat, the mother, fetus and future generations are at risk.
“There’s really this propensity to have more low birth weight babies,” Hanson said.
The study was unable to account for women who died during pregnancy and delivery, or for stillbirths and miscarriages. Grace said that this is an “area of interest” to do follow up work in.
The study also highlighted the impact of climate change on health all around the world. Other environmental issues such as air pollution have the potential to influence pregnancy development, and Grace said Utah is working to address this topic. Because of this, the study contributes to larger interests in the changing climate.
“I think that the information from this study can generate multiple hypotheses,” Hanson said. “A lot more research can be done.”