Adverse maternal and fetal outcomes in pregnant women recovering from asymptomatic COVID-19 and fetal Doppler ultrasound parameters

Introduction:
Coronavirus 2019 (COVID-19) is a newly emerging viral disease with multisystemic involvement. The aim of this study is to determine the changes in Doppler ultrasound (DUS) parameters, adverse maternal and fetal outcomes and maternal biochemical changes in the 3^rd trimester in pregnant women who experienced COVID-19 asymptomatically in the 1^st and 2^nd trimesters.

Material and methods:
This study is a tertiary center retrospective case-control study in which 223 pregnant women recovering from asymptomatic COVID-19 and 223 pregnant women who did not have COVID-19 were included. Medial cerebral artery (MCA) and umbilical artery (UA) vascular resistance parameters and cerebroplacental ratio (CPR) were determined by DUS for both groups. Adverse maternal outcomes (gestational diabetes mellitus [GDM], intrahepatic cholestasis of pregnancy [ICP], preeclampsia) and adverse fetal outcomes (preterm delivery, stillbirth, oligohydramnios, intrauterine growth restriction [IUGR], macrosomia and placental abnormalities) were noted in both groups. Statistical analy­ses were performed and p < 0.05 was considered significant.

Results:
UA-pulsatility index (PI) (p < 0.001), UA-resistivity index (RI) (p = 0.047), UA-systolic/diastolic (S/D) (p = 0.002), MCA-PI (p = 0.038), MCA-RI (p = 0.027) and MCA-S/D (p < 0.001) values increased in the group of pregnant women recovered from asymptomatic COVID-19. When biochemical values were assessed, total bilirubin value (p = 0.022) and glucose value (p < 0.001) were significantly higher in the group of pregnant women recovered from asymptomatic COVID-19. Gestational diabetes mellitus (p = 0.025), ICP (p = 0.023), preeclampsia (p = 0.036), preterm delivery (p = 0.02), IUGR (p < 0.001), and oligohydramnios (p = 0.002) rates were higher in pregnant women recovered from asymptomatic COVID-19.

Conclusions:
Even if COVID-19 has an asymptomatic course in pregnant women, it can cause maternal and fetal adverse outcomes. Changes in uteroplacental vascular structures after COVID-19 infection can be examined by Doppler ultrasonography to help prevent undesirable fetal and maternal complications.