No significant changes in preterm birth, low-birth-weight, and small-for-gestational-age infants during the first year of the COVID-19 pandemic in a rural area in Japan.

ABSTRACT

AIMS: To evaluate the coronavirus disease 2019 pandemic's impact on pregnancy outcomes in a Japanese rural area. METHODS: This retrospective study focused on the periods between March 1, 2020, and February 28, 2021 (during the coronavirus disease 2019 pandemic), and January 1, 2017, and December 31, 2019. Singleton pregnancies delivered at or after 22 gestational weeks were included. Preterm delivery, low-birth-weight, and small-for-gestational-age infant rates during the pandemic were compared to those in the preceding 3 years. RESULTS: In the pandemic and control groups, 1650 and 5762 pregnant women were included, respectively. Two pregnant women with coronavirus disease 2019 were identified (0.1%). There were no significant intergroup differences in preterm delivery rates (control, 4% vs. pandemic, 3.3%; difference -0.7% [95% confidence interval -1.7%-0.3%], p = 0.22). The low-birth-weight rate tended to decrease; however, the difference was insignificant (7.9% vs. 6.5%; difference -1.4% [95% confidence interval -2.8-0%], p = 0.06). The small-for-gestational-age infant rate was significantly lower in the pandemic than in the control group (7.3% vs. 5.2%; difference -2.1% [95% confidence interval -3.3-0.8%], p < 0.01). However, the interrupted time series analysis showed no significant trend. CONCLUSIONS: There were no significant changes in the rates of preterm delivery, low-birth-weight infants, and small-for-gestational-age infants during the pandemic's first year compared to those in the preceding 3 years. Behavioral changes, such as "stay-at-home" measures, may not improve pregnancy outcomes in Japan.