Increased risk of fetal loss after COVID-19 vaccination

Sir,

We read with interest the systematic review by Rimmer et al. (2023) and noted our manuscript (Thorp et al., 2022) that reported significant harms to pregnant women and infants was omitted. We performed a population-based retrospective cohort study assessing rates of adverse events (AEs) after COVID-19 vaccines experienced by women of reproductive age, focusing on pregnancy and menstruation, using data collected by the Vaccine Adverse Events Reporting System (VAERS) database from 1 January 1998 to 30 June 2022. The proportional reporting ratio comparing AEs reported after COVID-19 vaccines with those reported after influenza vaccines is significantly increased (≥2.0) for COVID-19 vaccine for menstrual abnormality, miscarriage, fetal chromosomal abnormalities, fetal malformation, fetal cystic hygroma, fetal cardiac disorders, fetal cardiac arrest, fetal arrhythmias, fetal vascular malperfusion, fetal growth abnormalities, fetal abnormal surveillance, placental thrombosis, fetal death/stillbirth, low amniotic fluid, preeclampsia, premature delivery, preterm premature rupture of membrane, and premature baby death. When normalized by time-available, doses-given, or number of persons vaccinated, all COVID-19 vaccine AEs far exceed the safety signal on all recognized thresholds. Specifically for miscarriage we found the global relative risk for was 177 (95% CI 114.4–283.5) compared to influenza vaccination. We believe inclusion of our data in Rimmer et al. (2023) would correct a Type II error and lead to a conclusion of excess harm, necessitating a worldwide moratorium on the use of COVID-19 vaccines in pregnancy.

Conflict of interest

Authors have no conflicts of interest to declare.