Pregnant people who are fully vaccinated against COVID-19 have a higher risk of breakthrough infection than vaccinated organ transplant recipients and those with weakened immune systems, new research suggests. It's a "striking" finding as the immunocompromised have taken precedence in the rollout of a fourth vaccine shot, reports the Washington Post. Researchers analyzed medical records of 13.8 million fully vaccinated US patients between January 2021 to January 2022 to find the risk of a breakthrough infection from 12 conditions, including pregnancy. They compared pairs of vaccinated patients from the same region, with each pair made up of one person who had a certain condition, and one who did not.
They found that the 110,000 pregnant patients were 90% more likely to be infected than the same number of patients who weren't pregnant. That was the highest risk among people with 12 conditions, including cancer. Compared to others without these conditions, organ transplant recipients were 80% more likely to be infected, those with compromised immune systems were 60% more likely to be infected, and patients with lung diseases were 30% more likely to be infected. Patients with cardiovascular diseases had no additional risk, while cancer patients had a lower risk of infection than those without cancer, per the Post.
The high risk for pregnant people is not understood, though it could be that they are more likely to be tested. Georges C. Benjamin, executive director of the American Public Health Association, says the findings indicate pregnant people "probably need a little more of the vaccine," per the Post. The study—which did not evaluate the severity of disease with the breakthrough infections—raises further research questions, including whether pregnant patients are at greater risk of severe disease or death, when is the best time for them to be vaccinated, and what dosage is best. Until those questions are answered, researchers say pregnant people should take extra precautions against COVID-19, per Axios. (Read more COVID-19 stories.)