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 haemodynamic in pregnancies complicated and in those not complicated by 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. Z-scores of head circumference, abdominal circumference, femur length and estimated fetal weight were compared between the 2 groups. Fetal growth was assessed analysing the growth velocity of head circumference, abdominal circumference, femur length and estimated fetal weight between the second and third trimester scan. Similarly, changes in the pulsatility index of uterine, umbilical, 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 compared to those without SARS-CoV-2 infection. There was no difference in either head circumference, abdominal circumference, femur length and estimated fetal weight z-scores between pregnancies complicated and those not complicated by SARS-CoV-2 infection both at the second and third trimester scan. 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's through gestation between the two groups. CONCLUSIONS: Pregnancies complicated by SARS-CoV-2 infection are not at higher risk of developing fetal growth restriction due to impaired placental function. The findings from this study do not support a policy of increased fetal surveillance in these women.