Before turning in for the night, pregnant women are advised to turn off the lights to lower their chance of getting gestational diabetes.

Pregnant women who are exposed to more light in the three hours before bed are more likely to develop diabetes during their pregnancy, according to research published in the American Journal of Obstetrics and Gynecology Maternal Fetal Medicine.

This coincides with the fact that the rates of non-communicable diseases, such as diabetes and obesity among Rwandans have been on the rise over the past 10 years especially in urban areas, as revealed by Dr. Sabin Nsanzimana, Minister of Health, during the National Dialogue Council, Umushyikirano.

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Diabetes, which occurs when your body does not make enough insulin, a hormone that helps regulate blood sugar levels, tends to worsen during pregnancy, a condition known as gestational diabetes.

Gestational diabetes is a form of diabetes that can occur during pregnancy in women who do not already have diabetes.

Other studies have found that people who work night shifts are more likely to develop type 2 diabetes because they are exposed to more outdoor artificial light at night, which has been related to a higher risk of the disease.

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It is believed that exposure to light at night inhibits melatonin levels, throws off the body's internal clock, and affects a number of metabolic processes such as the regulation of blood sugar levels.

Dr. Minjee Kim, a researcher at Northwestern University and the study's main author, together with colleagues, requested 741 expectant women in the US who were in their second trimester between 2011 and 2013 to wear light sensors on their wrists and keep a daily sleep journal for about a week.

They split the participants into three even-sized groups based on their median exposure to dim light in the three hours before sleep.

The results showed that 16 of the 247 women who only spent about 1.7 hours in dim light developed gestational diabetes, compared with 12 of those who spent about 2.2 hours in dim light, and three of those who spent about 2.6 hours in dim light.

Basically, women who spent the least time in dim light had fivefold greater chances of developing gestational diabetes compared to those who spent more time in dim light.

The research concluded that an association was present even when they took into account factors such as age, sleep quality, duration, body mass index, and how much light participants were exposed to during the day.

In addition to managing one's weight, eating healthily, and keeping active before pregnancy to reduce risks of gestational diabetes, it is also advised to at least dim lights three hours before bedtime, and avoid light-emitting devices such as phones, or put them on the night mode.