Variations in health behaviors among pregnant women during the COVID-19 pandemic.

The findings are self-reported and could be affected by recall or social desirability bias. The study measured behaviors at one survey time and can show associations, not cause and effect. Physical activity was assessed before and after March 2020, not specifically because of COVID-19, so changes could reflect pregnancy progression rather than the pandemic. Sleep was assessed only as less sleep because of the pandemic, not sleep quality or timing, and pregnancy itself can disrupt sleep. The sample was not representative of pregnant women in the United States: 70% had a bachelor's or graduate degree and 81% had a normal pre-pregnancy BMI. Women excluded from analysis differed from those included, being more likely to be non-Hispanic White, lower education, higher income, part-time or unemployed, underweight, and less physically active. Model sample sizes varied from 653 to 706 because of missing data, and 14 women who became active were excluded from physical activity analysis. Pandemic timing and local impact varied by area, and the authors note possible residual confounding and reverse causation for pregnancy complications.

This work was partially supported by a COVID-19 Research Initiative grant from the Office of the Vice President for Research at the University of South Carolina. Dr Liu reports grants from the University of South Carolina during the conduct of the study.

Do not read these associations as proof that the pandemic caused the behavior changes or that nursing advice will improve them. The study is self-reported survey data collected at one time, and physical activity changes may reflect pregnancy progression rather than pandemic response.