Association between Covid-19 in pregnancy and fetal growth patterns

Abstract

BACKGROUND: In the early stages of the COVID-19 pandemic there was evidence of adverse maternal and foetal outcomes including stillbirth and hypertensive disorders of pregnancy. Conversely there was minimal or conflicting data on the association with foetal growth restriction. We aimed to investigate the association between maternal COVID-19 infection and foetal growth. METHODS: Obstetric patients requiring admission or with self-reported COVID-19 infection were offered post infection surveillance as part of a local health district policy. Ultrasound was offered: 2 weeks post clearance of infection, 13 weeks, morphology at 19-22 weeks, and 28, 32 and 36 weeks for biometry and Doppler studies. Biometric measurements were compared against normative Hadlock values. RESULTS: From January 1, 2021 to January 31 2022 data was available from 284 ultrasound scans from 108 women who tested positive for COVID-19. The average number of scans per patient was 2.65 (SD 1.90). Foetal biometric measurements were not smaller (BPD median 72nd centile, P = 0.99; HC median 45th centile, P = 0.26; AC median 73rd centile, P = 0.65), except for FL (median 39th centile, P < 0.01). EFW was not smaller (median 66th centile, P = 0.98) and with negligible centile change on consecutive scans (median change -1 centile, 95% CI [-6, 1], P = 0.10). CONCLUSIONS: Our findings align with emerging international data suggestive that maternal COVID-19 infection, especially variants associated with the study period, was not associated with foetal growth restriction. This supports our recent move away from universal ultrasound surveillance post COVID-19 infection in pregnancy.