🚨As ICAN Warned, RSV Vaccine for Pregnant Women May Pose Risks Three years ago, @ICANdecide sent a letter to the FDA's vaccine advisory committee warning that Pfizer's RSV vaccine for pregnant women, Abrysvo, showed concerning safety signals in its clinical trials, including preeclampsia and fetal distress. The committee ignored the warning and recommended approval. A new study published in JAMA Network Open, sponsored by Pfizer itself, confirms what ICAN flagged. Pregnancy-associated hypertensive disorders occurred in 17.3 percent of vaccinated women, compared to 13.1 percent in the concurrent comparator group, an adjusted risk increase of up to 29 percent depending on the comparison group used. Premature rupture of membranes was also elevated, along with preterm premature rupture of membranes in the historical comparison. Even the study's own authors, despite the Pfizer funding, concluded that further studies are needed to refine these risk estimates.