Risk factors associated with adverse fetal outcomes in pregnancies affected by Coronavirus disease 2019 (COVID-19): a secondary analysis of the WAPM study on COVID-19

Abstract

Objectives: To evaluate the strength of association between maternal and pregnancy characteristics and the risk of adverse perinatal outcomes in pregnancies with laboratory confirmed COVID-19. Methods: Secondary analysis of a multinational, cohort study on all consecutive pregnant women with laboratoryconfirmed COVID-19 from February 1, 2020 to April 30, 2020 from 73 centers from 22 different countries. A confirmed case of COVID-19 was defined as a positive result on real-time reverse-transcriptase-polymerasechain-reaction (RT-PCR) assay of nasal and pharyngeal swab specimens. The primary outcome was a composite adverse fetal outcome, defined as the presence of either abortion (pregnancy loss before 22 weeks of gestations), stillbirth (intrauterine fetal death after 22 weeks of gestation), neonatal death (death of a live-born infant within the first 28 days of life), and perinatal death (either stillbirth or neonatal death). Logistic regression analysis was performed to evaluate parameters independently associated with the primary outcome. Logistic regression was reported as odds ratio (OR) with 95% confidence interval (CI). Results: Mean gestational age at diagnosis was 30.6±9.5 weeks, with 8.0% of women being diagnosed in the first, 22.2% in the second and 69.8% in the third trimester of pregnancy. There were six miscarriage (2.3%), six intrauterine device (IUD) (2.3) and 5 (2.0%) neonatal deaths, with an overall rate of perinatal death of 4.2% (11/ 265), thus resulting into 17 cases experiencing and 226 not experiencing composite adverse fetal outcome. Neither stillbirths nor neonatal deaths had congenital anomalies found at antenatal or postnatal evaluation. Furthermore, none of the cases experiencing IUD had signs of impending demise at arterial or venous Doppler. Neonatal deaths were all considered as prematurity-related adverse events. Of the 250 live-born neonates, one (0.4%) was found positive at RT-PCR pharyngeal swabs performed after delivery. The mother was tested positive during the third trimester of pregnancy. The newborn was asymptomatic and had negative RT-PCR test after 14 days of life. At logistic regression analysis, gestational age at diagnosis (OR: 0.85, 95% CI 0.8-0.9 per week increase; p<0.001), birthweight (OR: 1.17, 95% CI 1.09-1.12.7 per 100 g decrease; p=0.012) and maternal ventilatory support, including either need for oxygen or CPAP (OR: 4.12, 95% CI 2.3-7.9; p=0.001) were independently associated with composite adverse fetal outcome. Conclusions: Early gestational age at infection, maternal ventilatory supports and low birthweight are the main determinants of adverse perinatal outcomes in fetuses with maternal COVID-19 infection. Conversely, the risk of vertical transmission seems negligible.

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

“…They included 41 patients with SARS‐CoV‐2 infections, reporting that, among these, there was a 41.1% prevalence of preterm delivery < 37 weeks, 14.6% had pre‐eclampsia, 18.8% had preterm prelabor rupture of the membranes and in 7% there was perinatal death. A different report from the same authors 48 , analyzing 266 pregnant women who were positive for SARS‐CoV‐2, from 73 different centers and 22 countries, showed a prevalence of 26.3% ( n = 70) for preterm delivery, 2.3% ( n = 6) for stillbirth, 4.1% ( n = 11) for perinatal death and 3.8% ( n = 10) for fetal growth restriction. They explained that the increased rate of perinatal mortality was most probably related to prematurity.…”

Placental histopathology after SARS-CoV-2 infection in pregnancy: a systematic review and meta-analysis

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

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