A recent research reveals that those women who live in cold environments during pregnancy have lower risk of developing gestational diabetes than those in warm weathers.
One of the diseases that pregnant women can suffer from is gestational diabetes, which tends to appear in the second trimester. Although it commonly disappears after giving birth, it causes problems during pregnancy and childbirth and increases the risk of having type 2 diabetes in the future.
While it was already known that obesity, the age of the mother and history of diabetes in the family are factors associated with the possibility of suffering this serious disorder, the group of scientists found a new one: temperature.
Scientists at St. Michael’s Hospital and the Institute for Clinical Evaluative Sciences (ICES), both in Toronto, published a study in the Canadian Medical Association Journal that discusses the relationship between weather and the risk of gestational diabetes.
According to their study, women exposed to low temperatures during pregnancy are less likely to develop this type of diabetes than those at higher temperatures. The disease affected 4.6% of women who were subjected to extremely cold average temperatures (equal to or below -10 °C) in the 30-day period before being tested for diabetes during pregnancy. However, the risk increased to 7.7% when temperatures were much higher, above 24 °C. The authors also argue that, for every 10 °C increase in temperature, women have between 6 and 9% more chances of suffering this pathology.
To carry out the investigation, the researchers used data of 555,911 pregnancies among 396,828 women during a period of 12 years. They all resided in the Toronto metropolitan area, although they experienced different weathers during their pregnancy.
The relationship between the mean temperature of Toronto during the 30-day period prior to being screened for gestational diabetes —which pregnant women undergo during the second trimester of gestation— and incidence of gestational diabetes were analyzed.
The authors said that the results may seem counterintuitive to the naked eye, but they have their scientific explanation taking into account how different types of fat are generated in humans.
“You might think that with warmer temperatures pregnant women would be less sedentary, they would have more outdoor activity, and that would help them not gain weight, thing that usually favors the onset of diabetes,” explains Gillian Booth, lead author of the study. “However, this pattern coincides with that found in other studies that show that at lower temperatures the body creates a type of protective fat, brown adipose tissue or brown fat, which improves insulin sensitivity.”
The study included comparisons between consecutive pregnancies in the same woman. According to Joel Ray, co-author of the paper, “analyzing same woman’s pregnancies allows us controlling many factors. We can eliminate aspects such as ethnicity, income, activity or eating habits.”
Additionally, the results also revealed that the temperature of the environment during pregnancy was not the only factor to take into account, also influenced the weather of the place where the mothers were born. The study shows that women born in colder climates have a lower risk of developing this type of diabetes than those who did in warmer temperatures.
For example, those born in cold climates, including Canada and the United States, who also lived in cold places during the 30 days prior to diabetes testing, had a 3.6% risk of developing the disease, while those living in environments with high temperatures the risk grew to 6.3%.
By contrast, for women from warm climates, for example in South Asia, Africa and the Middle East, the percentage of risk increased to 7.7% when tested in cold weather and to 11.8% when tested in warm weather.
Source: Agencia SINC