Characteristics and Causes of Stillbirths Following Disruption to Antenatal Care During Implementation of COVID-19 Mitigation Measures.

Background and aim: Restrictions to mitigate COVID-19 transmission during the pandemic led to the disruption of routine antenatal care. We aimed to assess if those disruptions impacted the rates and types of stillbirths that occurred during that time.

Material and methods: We performed a retrospective cohort study of the types and causes of stillbirths occurring in women attending three maternity hospitals in Melbourne, Australia, to understand if COVID-19 mitigation measures altered them. Stillborn babies conceived between November 2019 and February 2020 (restriction exposed cohort) were compared with stillborn babies conceived between November 2017 and February 2018 or November 2018 and February 2019 (control cohort). Stillbirths were classified according to the Perinatal Society of Australia and New Zealand classification system (2018).

Results: In the exposed cohort, 29/2511 foetuses were stillborn (11.55 per 1000 births), compared to 53/5171 (10.25 per 1000 births) in the non-exposed cohort. No statistical difference in rates of stillbirth was found between the two groups (odds ratio [OR] 1.13, 95% CI 0.72 to 1.78, p = 0.603). The rate of pregnancy terminations was significantly lower in the exposed cohort (7.1% vs. 34.0%, p = 0.007), while the antepartum stillbirth rate was significantly higher (82.8% vs. 49.1%, p = 0.003), particularly for unexplained stillbirths (51.7% vs. 17.0%, p < 0.001). The rate of congenital abnormalities was lower in the exposed cohort (24.1% vs. 45.3%, p = 0.059), however, not significant.

Conclusions: Changes in routine antenatal care during the COVID-19 pandemic may have resulted in a decreased diagnosis of congenital abnormalities, subsequent decreased terminations of pregnancy and a significant increase in unexplained antepartum foetal deaths.