Preterm birth and stillbirth rates during the COVID-19 pandemic: a population-based cohort study

Abstract

reterm birth (birth before 37 weeks' gestation) is a leading cause of mortality and morbidities in the neonatal period, 1 childhood and adulthood. Stillbirth has devastating consequences for families. The causes of both preterm birth and stillbirth are multifactorial. During the pandemic, reports described reductions in preterm birth rates in Denmark, 4 the Netherlands, 5 Ireland 6 and the United States. At the same time, increases in stillbirth rates were reported from the United Kingdom, 8 Italy, 9 Nepal 10 and India, 11 with or without changes in rates of preterm births. Meta-analyses have emerged with differing conclusions. 12,13 Some speculated reasons for reductions in preterm births included reductions in physical activity during pregnancy, reduced stress related to work-life balance, less exposure to infection, fewer medical interventions, reduced travel and pollution, 14 and improved hygiene and rest. Proposed reasons for increases in preterm birth rates include higher stress due to worry about the pandemic, employment or financial challenges, home schooling and reduced maternity services. Less stringent fetal surveillance from reduced attendance at medical appointments for fear of infection, cancellation of face-to-face appointments and reduced staffing for maternity services are possible reasons for increased rates of stillbirths. Thus, it is important to evaluate preterm births and stillbirths simultaneously to understand the true impact. ome previous reports compared preterm birth and stillbirth rates during the pandemic to similar time periods in the past few years. However, within a jurisdiction, these rates are known to fluctuate between epochs 17 and, thus, it is preferable to evaluate rates over longer periods to establish whether observed variations are usual (common cause variation) or unusual (special cause variation). Our objective was to evaluate whether the COVID-19 pandemic affected preterm birth or stillbirth rates in Ontario by comparing rates for the early COVID-19 pandemic time period with rates from the previous 17.5 years to identify patterns of variation.