Effect of COVID-19 infection on pregnant women in plateau regions.

Objective: The present study aims to explore the effect of COVID-19 infection on pregnant women in plateau regions.

Study Design: Data from 381 pregnant women infected with COVID-19 who underwent prenatal examination or treatment at Women and Children's Hospital of Tibet Autonomous Region between January 2020 and December 2022 and 314 pregnant women not infected with COVID-19 were retrospectively collected.

Methods: The study participants were divided into an infected and non-infected group according to whether they were infected with COVID-19.

Can circulatory fetal DNA be used to study placentation at high altitude?

Pregnancy at high altitude (>2700 m) is associated with higher rates of fetal growth restriction and preeclampsia as well as alterations in placentation, including increased villous vascularization and reduced remodeling of maternal spiral arteries. Because circulatory fetal DNA concentrations were shown to be enhanced in pregnancies affected by preeclampsia, we investigated whether similar elevations are also apparent in pregnancies at high altitude by examining ethnic Tibetans and recent migrant Han Chinese residents in Lhasa (altitude 3650 m) as well as Han Chinese residents in Guangzhou (altitude 7 m). Our data from this preliminary study (n = 10/study group) indicate that circulatory fetal DNA levels were significantly higher in the unremarkable pregnancies of Han women who moved to Tibet when compared to Han women at sea level.