According to a recent study, antibodies that help in guarding against the COVID-19 virus are transferred from mothers to their babies while in the womb.
The research has been published in the ‘American Journal of Obstetrics and Gynecology’ that adds to an increasing evidence that suggests that pregnant women who generate protective antibodies after contracting the coronavirus often convey some of that natural immunity to their fetuses.
The findings also provide support to the idea that vaccinating mothers-to-be may also have benefits for their newborns. Dr Yawei Jenny Yang, an assistant professor of pathology and laboratory medicine at Weill Cornell Medicine and the study’s senior author, said, “Since we can now say that the antibodies that pregnant women make against COVID-19 have been shown to be passed down to their babies, we suspect that there’s a good chance they could pass down the antibodies the body makes after being vaccinated as well.”
Blood samples of about 88 women who gave birth at New York-Presbyterian/Weill Cornell Medical Center between March and May 2020, a time when New York City was the global epicentre of the pandemic were analyzed by Dr Yang and her team.
All of the women had COVID-19 antibodies in their blood which indicated that they had contracted the virus at some point even though 58 per cent of those women had no symptoms.
The vast majority of the babies born to these women were 78 per cent of the women who had detectable antibodies in their umbilical cord blood.
However, there was no evidence that any of the infants had been directly infected with the virus and each one was tested Covid negative at the time of the birth which shows that the antibodies had crossed the placenta (the organ that provides oxygen and nutrients to a growing baby during pregnancy) into the fetal bloodstream.
Moreover, the researchers observed that the concentration of antibodies was significantly higher in symptomatic women and the antibodies were detected in both symptomatic and asymptomatic women. Including that they also found that the general pattern of antibody response was same to the response seen in the other patients, confirming that pregnant women have the same kind of immune response to the virus as the larger population of the patients, hence it is something that hadn’t previously been known since a woman’s immune system changes throughout pregnancy.
Newborns with symptomatic mothers also had higher antibody levels than those whose mothers had no COVID symptoms. This data implies that pregnant women could pass along vaccine-generated antibodies in the same way, potentially shielding both mother and child from future infection.
However, it is not yet clear that how protective these antibodies might be, or how long that protection might last.
Dr Laura Riley, chair of the Department of Obstetrics and Gynecology at Weill Cornell Medicine, obstetrician and gynaecologist-in-chief at NewYork-Presbyterian/Weill Cornell, and one of the study’s co-authors, is still advising pregnant patients who decide to get vaccinated to continue to follow current safety guidelines to prevent the spread of the disease.
Dr Riley, Dr Yang, and their colleagues are leading follow-up investigations that are currently enrolling pregnant women who receive the vaccine, as well as vaccinated mothers who are breastfeeding, to assess the antibody response in those groups after vaccination. That information could help guide maternal vaccination strategies moving forward.
“The USD 1 million question is: Will the group of women who are now being vaccinated get the same type of protection? We don’t know that yet,” Dr Riley said. “Getting those answers is going to be really important.”