NEW YORK: Expectant mothers should stay out of the sun this summer, according to new research.
Warm weather is linked to temporary diabetes during pregnancy, the study found.
The complication occurs in 4.6 per cent of women exposed to average temperatures of -10°C (14°F) or colder, the findings revealed.
Yet for those exposed to temperatures of 24°C (75°F) or higher, 7.7 per cent of women develop the condition, known as gestational diabetes.
Gestational diabetes can lead to pregnancy complications including premature birth and jaundice, as well as increasing the chances of childhood obesity later in life.
Researchers from the Canadian Institute of Health Research analysed 555,911 births among 396,828 women living in the Greater Toronto Area over a 12-year period (2002 to 2014).
The average age of mothers when giving birth was 31.
Gestational diabetes occurred in 4.6 per cent of women exposed to average temperatures of -10°C (14°F) or colder.
For those exposed to temperatures of 24°C (75°F) or higher, 7.7 per cent of women developed gestational diabetes.
Gestational diabetes occurs when hormones in the placenta trigger resistance to insulin – a hormone that regulates blood sugar levels.
Study author Dr Gillian Booth, said: ‘We observed a direct relation between outdoor temperature and the risk of gestational diabetes among nearly 400,000 women residing in a single urban area in Canada.
‘Within this confined geographical region, where there are wide fluctuations in temperature across seasons, the absolute difference in the rate of gestational diabetes was more than three per cent between the hottest and coldest outdoor air temperatures.’
Dr Booth said the findings may be explained by emerging science about how humans make different kinds of fat.
She said: ‘Many would think that in warmer temperatures, women are outside and more active, which would help limit the weight gain in pregnancy that predisposes a woman to gestational diabetes.