Ultrasound and Doppler findings in pregnant women with SARS-CoV-2 infection

To describe and compare ultrasound and Doppler findings in pregnant women who were positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with findings in those who were SARS-CoV-2-negative, evaluated during the pandemic period.

In this retrospective case-control study, we analyzed data from 106 pregnant women who tested positive for SARS-CoV-2 at the time of, or within 1 week of, an ultrasound scan between 1 May and 31 August 2020. Scans were either performed for routine fetal evaluation or indicated due to a positive SARS-CoV-2 test. Forty-nine women were symptomatic and 57 were asymptomatic. For comparison, we analyzed data from 103 pregnant women matched for maternal age, parity, body mass index and gestational age at the time of the ultrasound scan. These control women did not report symptoms of SARS-CoV-2 infection at the time of the ultrasound scan or at the time of admission for delivery and had a negative SARS-CoV-2 test at admission for delivery. Fetal biometry, fetal anatomy, amniotic fluid volume and Doppler parameters, including umbilical and fetal middle cerebral artery pulsatility indices, cerebroplacental ratio and biophysical profile (BPP), were evaluated as indicated. Biometric and Doppler values were converted to Z-scores for comparison. Our primary outcome, an adverse prenatal composite outcome (APCO) included any one or more of: small-for-gestational-age (SGA) fetus, oligohydramnios, abnormal BPP, abnormal Doppler velocimetry and fetal death. Comorbidities, delivery information and neonatal outcome were compared between the two groups.

Eighty-seven (82.1%) women who were positive for SARS-CoV-2 had a body mass index > 25 kg/m² . SARS-CoV-2-positive women had a higher prevalence of diabetes (26/106 (24.5%) vs 13/103 (12.6%); P = 0.03), but not of pre-eclampsia (21/106 (19.8%) vs 11/103 (10.7%); P = 0.08), compared with controls. The prevalence of APCO was not significantly different between SARS-CoV-2-positive women (19/106 (17.9%)) and controls (9/103 (8.7%)) (P = 0.06). There were no differences between SARS-CoV-2-positive women and controls in the prevalence of SGA fetuses (12/106 (11.3%) vs 6/103 (5.8%); P = 0.17), fetuses with abnormal Doppler evaluation (8/106 (7.5%) vs 2/103 (1.9%); P = 0.08) and fetuses with abnormal BPP (4/106 (3.8%) vs 0/103 (0%); P = 0.14). There were two fetal deaths in women who were positive for SARS-CoV-2 and these women had a higher rate of preterm delivery ≤ 35 weeks of gestation (22/106 (20.8%) vs 9/103 (8.7%); odds ratio, 2.73 (95% CI, 1.19-6.3); P = 0.01) compared with controls.

There were no significant differences in abnormal fetal ultrasound and Doppler findings observed between pregnant women who were positive for SARS-CoV-2 and controls. However, preterm delivery ≤ 35 weeks was more frequent among SARS-CoV-2-positive women. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.