Darkness is important for optimum reproductive health in women, and for protecting a developing fetus, according to study researcher Russel J. Reiter, PhD, a professor of cellular biology at the University of Texas Health Science Center in San Antonio.
To conduct their research, Dr. Reiter and his colleagues evaluated previously published research on the role of melatonin levels and circadian rhythms on successful reproduction in women. Their findings, which were published earlier this month in the journal Fertility and Sterility, suggest that women who want to become pregnant or those who are expecting a baby should avoid light during the night.
Eight hours of darkness nightly is ideal, with no interruptions, especially during the last trimester of a pregnancy. Turning on the light at night suppresses melatonin production in women and means that the fetal brain may not get the proper amount of melatonin to regulate its biological clock.
The light-dark cycle should be regular from day to day to avoid confusing the biological clock. Their study evidence indicates that every time you turn on light at night, the production of melatonin diminishes. Melatonin is a hormone secreted by the pineal gland in the brain as a response to darkness. It’s important for pregnant women and those trying to conceive because it protects their eggs from oxidative stress and has strong antioxidant properties that shield the egg from free-radical damage, especially during ovulation.
“Sleep is nice, but it is the actual darkness that’s necessary for the brain to produce melatonin,” says Dr. Reiter. “So there is a biological price to pay for disturbing with light.”
He advises making sure that the bedroom is dark, and avoiding the glare of television and electronic gadgets. For those who want a night light, choose a red or yellow light that won’t be disturbing to circadian rhythms like a white or blue light. If you can’t sleep, rest…and avoid turning on a light.