#Pregnancy #COVID-19 #Vaccination
#VaccineSafety #SARS
Pregnant women are at increased risk of severe
complications when infected with SARS-CoV-2. Infection can lead to adverse
outcomes such as preterm birth, the need for intensive care hospitalization,
and in the most severe cases, maternal or neonatal death. This vulnerability is
due to immunological and physiological changes during pregnancy, which make
pregnant women more susceptible to severe respiratory infections and their
consequences.
Despite this reality, vaccination coverage
among pregnant women remains insufficient worldwide. This gap is mainly
explained by the initial lack of data regarding the safety and efficacy of
COVID-19 vaccines in pregnant women. Clinical trials conducted during vaccine
development systematically excluded this population, generating uncertainty and
hesitation among both patients and healthcare professionals. This
data gap
delayed the establishment of clear recommendations and hindered trust in
vaccination, even though the risks of complications remained high.
In this context, this research focuses on
studying the safety and efficacy of COVID-19 vaccines administered during
pregnancy, aiming to provide updated, evidence-based answers to better guide
recommendations, reassure pregnant women, and improve their level of protection
against COVID-19.
Vaccinated mother, protected baby?
To achieve this, 177 studies involving over
630,000 pregnant women from 41 countries were selected and analyzed. All
recognized vaccine types (mRNA, viral vector, inactivated virus) were included.
The findings show that COVID-19 vaccination
during pregnancy does not increase the risk of maternal or neonatal adverse
events (such as miscarriage, gestational diabetes, hypertension, congenital
anomalies, or prematurity). On the contrary, a reduction in the risk of
stillbirth (up to –75% with mRNA or viral vector vaccines) and emergency
cesarean deliveries was observed.
Regarding vaccine safety, reported side effects
are mostly local (injection site pain) or mild (fatigue, headache), with their
frequency being similar to or even lower in pregnant women compared to the
general population. Severe adverse events remain rare.
In terms of efficacy, mRNA vaccination during
pregnancy significantly reduces the risk of symptomatic COVID-19, severe forms,
or hospitalization in the mother (with efficacy ranging from 72% to 82%).
Protection is also partially transferred to the newborn. A decrease in
hospitalizations for COVID-19 within the first six months of life has indeed
been observed. Overall efficacy is lower for non-mRNA vaccines and during
periods dominated by the Omicron variant, but the benefit remains noteworthy.
Vaccinated mothers, risks averted!
COVID-19 exposes pregnant women to a
high risk
of severe complications, affecting both the mother and the newborn. Despite the
severity of the issue, vaccination during pregnancy remains underutilized,
partly due to the initial lack of specific data, the emergence of new variants,
and persistent hesitations regarding vaccine safety in this population.
The aim of this review was to provide an
updated evaluation of the effectiveness and safety of COVID-19 vaccines
administered during pregnancy, in order to inform clinical practices and
strengthen the prevention of severe cases.
The results confirm that vaccination effectively protects pregnant women
against severe COVID-19 and reduces the risk of complications in newborns,
without increasing obstetric or neonatal adverse events. The protective effect
is particularly pronounced against the Alpha and Delta variants.
However, the generalization of these results is
limited by the predominance of observational studies, protocol heterogeneity,
the lack of randomized trials, and the underrepresentation of low-resource
countries or non-mRNA vaccines. The reduced efficacy observed with the Omicron
variant also highlights the importance of booster vaccinations and prolonged
follow-up.
It is therefore crucial to continue research,
expand studies to diverse contexts, and continually update recommendations to
ensure the best possible protection for pregnant women.
Optimizing vaccination
prevention during pregnancy must remain a priority to reduce maternal and
neonatal mortality and to offer mothers and their children the best chances of
safely navigating the pandemic.
Read next: Pregnancy under surveillance: infections—who really protects?
