Effect of SARS-CoV-2 infection on fetal umbilical vein flow and cardiac function: a prospective study.

OBJECTIVES: To explore whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can affect umbilical vein blood flow (UVBF) and fetal cardiac function. METHODS: Prospective case-control study of consecutive pregnancies complicated by SARS-CoV-2 infection during the second half of pregnancy matched with unaffected women. Measurements of UVBF normalized for fetal abdominal circumference (UVBF/AC), atrial area (AA) and ventricular sphericity indices (SI) were compared between the two study groups. Chi-square and Mann-Whitney U tests were sued to analyze the data. RESULTS: Fifty-four consecutive pregnancies complicated and 108 not complicated by SARS-CoV-2 infection were included. The median gestational age at infection was 30.2 (interquartile range [IQR] 26.2 34.1). General baseline and pregnancy characteristics were similar between pregnant women with compared to those without SARS-CoV-2 infection. There was no difference in UVBF/AC (study groups z value -0.11 vs. 0.14 control p 0.751) values between pregnancies complicated compared to those not complicated by SARS-CoV-2 infection. Likewise, there was no difference in the left and right AA (left 1.30 vs. 1.28 p=0.221 and right 1.33 vs. 1.31 p=0.324) and SI (left 1.75 vs. 1.77 p=0.208 and right 1.51 vs. 1.54 p=0.121) between the two groups. CONCLUSIONS: SARS-CoV-2 infection does not affect UVBF and fetal cardiac function in uncomplicated pregnancies.

Effect of SARS-CoV-2 infection during the second half of pregnancy on fetal growth and hemodynamics: A prospective study.

INTRODUCTION: Our objective was to compare the fetal growth velocity and fetal hemodynamics in pregnancies complicated and in those not complicated by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. MATERIAL AND METHODS: Prospective case-control study of consecutive pregnancies complicated by SARS-CoV-2 infection during the second half of pregnancy matched with unaffected women. The z scores of head circumference, abdominal circumference, femur length, and estimated fetal weight were compared between the two groups. Fetal growth was assessed by analyzing the growth velocity of head circumference, abdominal circumference, femur length, and estimated fetal weight between the second- and third-trimester scans. Similarly, changes in the pulsatility index of uterine, umbilical, and middle cerebral arteries, and their ratios were compared between the two study groups. RESULTS: Forty-nine consecutive pregnancies complicated, and 98 not complicated, by SARS-CoV-2 infection were included. General baseline and pregnancy characteristics were similar between pregnant women with and those without SARS-CoV-2 infection. There was no difference in head circumference, abdominal circumference, femur length, and estimated fetal weight z scores between pregnancies complicated and those not complicated by SARS-CoV-2 infection at both the second- and third-trimester scans. Likewise, there was no difference in the growth velocity of all these body parameters between the two study groups. Finally, there was no difference in the pulsatility index of both maternal and fetal Doppler scans throughout gestation between the two groups. CONCLUSIONS: Pregnancies complicated by SARS-CoV-2 infection are not at higher risk of developing fetal growth restriction through impaired placental function. The findings from this study do not support a policy of increased fetal surveillance in these women.