Seriously, Vaginal Seeding Needs to Stop

It seems that, in our zeal to toss bacteria onto babies, we forgot that some microbes are not our friends.

Vaginal seeding never quite sounded right. The theory was that C-section babies, deprived of the healthy bacteria obtained from the vagina during normal birth, might benefit from having vaginal microbes rubbed onto their sterile newborn faces. But now the American College of Obstetrics and Gynecology has ruled the procedure unnecessary and, in some cases, downright dangerous.

“Patients who may need to undergo a C-section are increasingly seeking counsel from Ob-Gyns on whether vaginal seeding is appropriate,” said Christopher Zahn of ACOG in a statement. “However, due to the lack of sufficient data, the very real risks outweigh the potential benefits.”

Vaginal seeding makes sense, in theory. We now know that the vast majority of microbes colonizing our skin and stomachs are not only harmless, but essential. Preliminary studies suggest that infants born with deficient microbiomes may suffer from higher rates of asthma and allergies.

C-section infants, however, largely miss out on this microbial boost — they’re born under sterile, surgical conditions. This prompted scientists to investigate whether “seeding” such children with vaginal microbes, by swabbing vaginal fluids on their eyes and mouth shortly after birth, could help them catch up their well-colonized peers. Believe it or not, initial studies suggested it just might.

But it seems that in our zeal to toss bacteria onto babies, we forgot that some microbes are not our friends. Vaginal seeding can inadvertently transfer herpes, chlamydia, and gonorrhea to newborns, especially since these diseases often go undetected in new mothers. Worse, there’s a real risk of transferring the deadly Group B Streptococcus bacteria, which is responsible for more than 150,000 infant deaths worldwide. When these risks are weighed against the potential gains (studies have yet to demonstrate conclusively that vaginal seeding benefits babies) the choice to abstain is obvious.

Besides, nobody needs vaginal swabs to build their babies’ microbiomes. Among the many benefits of breastfeeding is the fact that the nipple itself helps babies get the good bacteria they need. “The bacteria present in breast milk and on the nipple is sufficient for natural colonization or seeding of the gut,” Zahn said. “There may be some initial difference in the gut microbiota of infants based on mode of delivery, but research has shown that difference disappears after about six months.”