Night time owls with gestational diabetes might face greater threat of being pregnant problems


WASHINGTON – According to a study, the results of which will be presented at ENDO 2021, the annual meeting of the Endocrine Society, night owls have a higher risk of maternal and child complications than early risers in women who develop diabetes during pregnancy.

Compared to other pregnant women with gestational diabetes, those with a preference for evening activity were three times more likely to have preeclampsia, pregnancy-related high blood pressure, and a four times higher rate of treating their newborns in a neonatal intensive care unit, the study’s investigators reported.

These results suggest a new potential health risk from disruptions to the body’s 24-hour internal clock, particularly the sleep-wake cycle, said lead investigator Cristina Figueiredo Sampaio Facanha, MD, an endocrinologist at the Federal University of Ceara’s Diabetes Center (Universidade ) Federal do Ceara) in Fortaleza, Brazil.

“Circadian arrhythmias could put an additional risk of poor pregnancy outcomes in women with gestational diabetes,” said Facanha, director of the center’s pregnancy diabetes division.

Gestational diabetes, a form of diabetes during pregnancy, can alone increase the mother’s risk of premature delivery and preeclampsia, as well as the baby’s risk of growing too big in the womb or having difficulty breathing after birth. This type of diabetes affects four to eight in 100 pregnant women in the US and ten in 100 pregnant women in Brazil, according to estimates by the Hormone Health Network and the International Diabetes Federation.

Previous research shows associations between adverse health effects and chronotype, an individual’s propensity for when to sleep and when to feel peak energy. An evening chronotype describes when someone feels more active in the evening and goes to bed very late, while early risers have a morning chronotype. People with the evening chronotype tend to have more depression, anxiety, dinner, and an unhealthy lifestyle than people with a morning chronotype, Facanha noted.

“Hormones, blood pressure and glucose or blood sugar metabolism follow circadian rhythms that synchronize with a master clock in the brain,” said Facanha. “If the circadian rhythm for the sleep-wake cycle is switched off, it can not only lead to sleep problems, but also impair glucose metabolism and impair the health of the pregnancy.”

The researchers wanted to find out whether the chronotype influences pregnancy complications in women with gestational diabetes and their newborns. They looked at 305 women with this type of diabetes in their second and third trimesters of pregnancy. The women completed questionnaires about their chronotype preferences, sleep quality, daytime sleepiness, and symptoms of depression.

Almost half of the study participants – 151 women – had a morning chronotype, which is in line with recent research that pregnancy induces an earlier chronotype, Facanha said. Another 21 women had the evening chronotype. The remaining 133 participants did not have a strong chronotype and were classified as intermediate.

Compared to women with other chronotypes, women with an evening preference reported significantly more severe symptoms of depression both before and after pregnancy, as well as poorer sleep quality, insomnia, and daytime sleepiness. Even after the researchers checked depression symptoms and sleep variables in their statistical analyzes, the evening chronotype remained an independent risk factor for preeclampsia, Facanha said.

She suggested that women with gestational diabetes should be screened to determine their chronotype using a simple questionnaire as part of routine prenatal care. “This could be helpful in predicting pregnancy complications,” Facanha said.

“Women can potentially reduce their evening preference,” Facanha said. “Changing habits and increasing exposure to natural light in the morning, exercise, and decreasing blue-screen light are all accessible treatments that can potentially improve health interventions during pregnancy.”


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