Reduction in preterm birth rates during and after the COVID-19 lockdown in Queensland Australia

Preventative strategies for preterm birth are lacking. Recent evidence proposed COVID-19 lockdowns may have contributed to changes in preterm birth.

To determine the prevalence of preterm birth and birth outcomes during and after the COVID-19 lockdown at the Sunshine Coast University Hospital and the overall state of Queensland, Australia.

Retrospective cohort analysis of all births in Queensland including the Sunshine Coast University Hospital, during two epochs, April 1-May 31, 2020 (lockdown) and June 1-July 31, 2020 (post-lockdown), compared to antecedent calendar-matched periods in 2018-2019. Prevalence of preterm birth, stillbirth, and late terminations were examined.

There were 64 989 births in Queensland from April to July 2018-2020. At the Sunshine Coast University Hospital, there was a significantly higher chance of birth at term during both lockdown (odds ratio (OR) 1.81, 95% CI 1.17, 2.79; P = 0.007) and post-lockdown (OR 2.01, 95% CI 1.27, 3.18; P = 0.003). At the same centre, prevalence of preterm birth was 5.5% (30/547) during lockdown, compared to 9.1% (100/1095) in previous years, a 40.0% relative reduction (P = 0.016). At this centre during lockdown, emergency caesareans concurrently decreased (P < 0.01) and instrumental vaginal births increased (P < 0.01). In Queensland overall, there was a nonsignificant decrease in the prevalence of preterm birth during lockdown.

There is a link between lockdown and a reduction in the prevalence of preterm birth on the Sunshine Coast. The cause is speculative at present, although increased influenza vaccination rates, decreased transmission of infections, and improved air quality may have been favourable in reducing preterm birth. Further research is needed to determine a causal link.