1. It's not a trial. These women voluntarily had the COVID vaccine 2. They used data from a "v-safe" vaccine health checker these women voluntarily opted to provide info 3. Of the 35 691 v-safe participants who were all pregnant. Pain at the injection site was the biggest reported problem, followed by headache, chills and fever though these were less common 4. The study identified similar adverse pregnancy incidences as comparable to those in pregnant women prior to COVID 5. The preliminary findings identified no obvious safety signals however they recommend further longitudinal studies
So what you imply is completely wrong to what they evidence suggests.
