COVID-19 vaccination in pregnancy
Lan N Vuong1,2, Minh N Chau2,3, Duy
L Nguyen2, Toan D Pham2, Ben W
Mol4, Tuong M Ho2,3
1University of Medicine and Pharmacy at Ho Chi Minh
City, Ho Chi Minh City, Vietnam
2HOPE Research Center, My Duc Hospital, Ho Chi Minh
City, Vietnam
3My Duc Hospital, Ho Chi Minh City, Vietnam
4Department of Obstetrics and Gynaecology, School of
Clinical Sciences at Monash Health, Monash University, Melbourne,
Victoria, Australia
Dear Editor,
Vaccination has been the most effective strategy against Covid-19
disease caused by SARS-CoV-2. In view of the disruptive nature of the
pandemic, vaccines have understandably been approved after shortened
assessment trajectories. Pregnant women face more than double the risk
of needing admission to an intensive care unit, intensive ventilation,
extracorporeal membrane oxygenation and death.1
Early studies on vaccination in pregnant women showed no increased risk
of pregnancy complications, but the studies were retrospective and
limited to Pfizer-BioNTech.2,3 Here, we compare
pregnancy and neonatal outcomes in Vietnamese women vaccinated against
COVID-19 with Astra Zeneca and Pfizer-BioNTech.
Methods Between August 2021 and November 2021, 954 pregnant
women were offered vaccination against COVID-19 at around 30-31 weeks of
gestation at My Duc Hospital, Ho Chi Minh City, Vietnam. The choice for
Astra Zeneca or Pfizer-BioNTech vaccines depended on the availability of
the vaccines at the time of vaccination. We prospectively investigated
the side effects in the vaccinated pregnant women within 1 week after
vaccination and followed their pregnancies till deliveries.
Results There were 441 pregnant vaccinated with Astra Zeneca
and 513 with Pfizer-BioNTech. Women receiving Pfizer-BioNTech were
slightly older, more often multiparous, more often had conceived
spontaneously, and more often (80.7% versus 60.1%) had received two
doses. There were more side-effects reported after Astra Zeneca, but
they were all mild (Table 2).
There were more women with preeclampsia and gestational diabetes
mellitus after vaccination with Pfizer-BioNTech as compared to Astra
Zeneca (both 1.0% versus 0.2%), but differences were not statistically
significant (Table 3). The rate of birthweight <2500 gram was
2.5% after Astra Zeneca and 5.3% after Pfizer (RR 2.1; 95% CI 1.05,
4.18, P-value 0.046). Table 4 shows that this is due to a higher rate of
growth restriction and not due to more preterm birth.