Preterm Birth and Stillbirth During the COVID-19 Pandemic in Sweden: A Nationwide Cohort Study

A recent Danish study reported that the rate of extremely preterm birth was reduced during the lockdown period of the coronavirus disease 2019 (COVID-19) pandemic; the odds ratio (OR) was 0.09 (95% CI, 0.01 to 0.40) compared with previous years. Given the lockdown measures, potential mechanisms might include reduced exposure to various infectious agents, physical work strain, or stress; another explanation might be an increase in stillbirth, as the Danish study was based on live births. A study from the United Kingdom reported that stillbirth was more common during the pandemic; the difference was 6.93 cases per 1000 births, corresponding to a 4-fold risk increase. To investigate associations between being born during a period when many public health interventions aimed at mitigating the spread of COVID-19 were enforced and the risk for preterm birth and stillbirth.