Association between maternal Sars-Co-V2 infection and fetal growth restriction (FGR) at a single county hospital

ABSTRACT

Objective: Prior studies have shown maternal viral infections are associated with fetal growth restriction (FGR);however, the relationship between FGR and Sars-CoV-2 (SCOV2) infection during pregnancy remains unclear. In this study, we investigate the association between FGR & parental SCOV2 infection at a county hospital in Atlanta, Georgia. Study Design: A prospective cohort study was created by matching patients who had positive SCOV2 (PSCOV2) and negative SCOV2 (NSCOV2) PCR tests between 1/2020-4/2021 utilizing an institutional database. Cohorts were drawn from patients who received a 3rd trimester ultrasound (3TUS) & were matched by gestational age & month SCVO2 testing was performed. FGR was present when estimated fetal weight (EFW) was ≤10% or abdominal circumference (AC) ≤10% at time of either late 2nd or 3rd trimester ultrasound. Sample size calculations were performed to investigate a 15% difference in FGR rate requiring 74 subjects per group. Univariate analyses, chi-square tests and logistic regression were performed. Regression models were adjusted for comorbidities including preeclampsia, gestational diabetes, chronic hypertension, gestational hypertension, and maternal race. Results: 157 subjects were in the analyses (n=78 PSCOV2 and n=79 NSCVO2). 83.4% (n =131) self-identified as African American. FGR rates were 15.3% and 16.4% among PSCOV2 and NSCOV2 respectively. After adjusting for confounders, no difference in FGR was observed between the groups (adjusted OR 1.12, 95% CI 0.46-2.73). Absolute EFW at time of FGR diagnosis was lower in PSCOV2 vs NSCOV2 (1,250 grams vs.1,337 grams, p= 0.015), a relationship that remained after adjusting for confounders (p=0.015). Conclusion: Our data suggest that despite a high background FGR rate (15.2%), there was no significant association between FGR and SCOV2. Also, EFW was lower in PSCOV2 cohort vs NSCOV2 cohort. Therefore, unlike other viral illnesses, while SCOV2 may not clinically drive FGR, further studies are necessary to investigate the effects of maternal SCVO2 on fetal growth & examine whether growth exams improve outcomes in this setting.