ABSTRACT
Objective
To evaluate the effects of coronavirus disease 2019 (COVID‐19) on maternal, perinatal
and neonatal outcomes by performing a systematic review of available published literature
on pregnancies affected by COVID‐19.
Methods
We performed a systematic review to evaluate the effects of COVID‐19 on pregnancy,
perinatal and neonatal outcomes. We conducted a comprehensive literature search using
PubMed, EMBASE, the Cochrane Library, China National Knowledge Infrastructure Database
and Wan Fang Data until 20 April 2020 (studies were identified through PubMed alert
after that date). For the research strategy, combinations of the following keywords
and MeSH terms were used: SARS‐CoV‐2, COVID‐19, coronavirus disease 2019, pregnancy,
gestation, maternal, mothers, vertical transmission, maternal‐fetal transmission,
intrauterine transmission, neonates, infant, delivery. Eligibility criteria included
laboratory‐confirmed and/or clinically diagnosed COVID‐19, patient being pregnant
on admission and availability of clinical characteristics, including at least one
maternal, perinatal or neonatal outcome. Exclusion criteria were non‐peer‐reviewed
or unpublished reports, unspecified date and location of the study, suspicion of duplicate
reporting, and unreported maternal or perinatal outcomes. No language restrictions
were applied.
Results
We identified a high number of relevant case reports and case series, but only 24
studies, including a total of 324 pregnant women with COVID‐19, met the eligibility
criteria and were included in the systematic review. These comprised nine case series
(eight consecutive) and 15 case reports. A total of 20 pregnant patients with laboratory‐confirmed
COVID‐19 were included in the case reports. In the combined data from the eight consecutive
case series, including 211 (71.5%) cases of laboratory‐confirmed and 84 (28.5%) of
clinically diagnosed COVID‐19, the maternal age ranged from 20 to 44 years and the
gestational age on admission ranged from 5 to 41 weeks. The most common symptoms at
presentation were fever, cough, dyspnea/shortness of breath, fatigue and myalgia.
The rate of severe pneumonia reported amongst the case series ranged from 0 to 14%,
with the majority of the cases requiring admission to the intensive care unit. Almost
all cases from the case series had positive computer tomography chest findings. All
six and 22 cases that had nucleic‐acid testing in vaginal mucus and breast milk samples,
respectively, were negative for SARS‐CoV‐2. Only four cases of spontaneous miscarriage
or abortion were reported. In the consecutive case series, 219/295 women had delivered
at the time of reporting, and the majority of these had Cesarean section. The gestational
age at delivery ranged from 28 to 41 weeks. Apgar scores at 1 and 5 min ranged from
7 to 10 and 7 to 10, respectively. Only eight neonates had birth weight <2500 g and
nearly one‐third of cases were transferred to the neonatal intensive care unit. There
was one case each of neonatal asphyxia and neonatal death. In 155 neonates that had
nucleic‐acid testing in throat swab, all, except three cases, were negative for SARS‐CoV‐2.
There were seven maternal deaths, four intrauterine fetal deaths (one with twin pregnancy)
and two neonatal deaths (twin pregnancy) reported in a non‐consecutive case series
of nine cases with severe COVID‐19. From the case reports, two maternal deaths, one
neonatal death and two cases of neonatal SARS‐CoV‐2 infection were reported.
Conclusions
Despite the increasing number of published studies on COVID‐19 in pregnancy, there
are insufficient good‐quality data to draw unbiased conclusions with regard to the
severity of the disease or specific complications of COVID‐19 in pregnant women, as
well as vertical transmission, perinatal and neonatal complications. In order to answer
specific questions in relation to the impact of COVID‐19 on pregnant women and their
fetuses through meaningful good‐quality research, we urge researchers and investigators
to present complete outcome data and reference previously published cases in their
publications, and to record such reporting when the data of a case are entered into
a registry or several registries.
This article is protected by copyright. All rights reserved.