(CNN) Parents are faced with a lot of difficult questions when they're getting ready to give birth. Should the mother get an epidural? Is saving umbilical cord blood worth it? They may even ponder eating the placenta.
Now add to the list whether to follow a trend known as "vaginal seeding." The practice involves swabbing the vagina of women who are going to have a cesarean delivery and then wiping the fluids on the baby. The hope is to give the baby the bacteria it would have been exposed to during vaginal delivery and help kickstart a healthy gut microbiome.
Although few doctors in the United States seem to be offering this simple procedure, a growing number of women are inquiring about it.
"It's certainly happening more frequently (whereas) maybe like five or 10 years ago, I don't think anybody really asked about this," said Dr. Leonardo Pereira, chief of maternal-fetal medicine at Oregon Health & Science University.
Interest in the practice seems to be percolating overseas as well. "(By) taking a straw poll amongst colleagues at our hospital and other hospitals (in the United Kingdom), it seems in the last year or two almost all of the obstetricians and neonatologists here have encountered women asking for this to be done," said Dr. Aubrey J. Cunnington, a pediatrician at Imperial College London.
A large body of research points to an association between C-section delivery and increased risk of asthma, obesity and other health conditions. On the other hand, there has been an "absolute explosion of research on the role of the microbiota in health and disease," Cunnington said.
However, experts say it is far too soon to say whether the vaginal microbiome gives babies a healthier start, and if so, whether seeding has the same beneficial effect as a vaginal delivery. Of greater concern is whether the practice could expose babies to some disease-causing bacteria in the bypassed birth canal.
In spite of the growing interest in vaginal seeding, there is a lack of data on its safety and benefits, and a lack of guidance for women and their doctors, Cunnington said. He and his colleagues in the United Kingdom and Australia took a close look at the issues surrounding the practice in an article that was published on Tuesday in the British Medical Journal.
"I think it would be helpful to have some guidelines on this, [but] it's very hard to make guidelines when you have almost no evidence," said Cunnington, who delivered babies before he started specializing in pediatric infectious disease. "Hopefully (the article) will help the medical profession to feel they have a little support," whether they decide to practice vaginal seeding or not, he said.
The main qualm doctors have with vaginal seeding is that it could infect babies with dangerous bugs at the same time it is bestowing them with potentially healthy bacteria. Topping the list of pathogens of concern are group B streptococcus, chlamydia and gonorrhea.
The Centers for Disease Control and Prevention recommends testing all pregnant women for these bacteria, as well as a number of other pathogens. About a quarter of all women harbor group B streptococcus, and while they may not experience symptoms, the bacteria could cause pneumonia and meningitis in their newborns.
All women should get screened, even those planning to have a C-section, in case they end up having an unexpected vaginal delivery, Pereira said. If they are infected, women can receive antibiotics during labor to prevent passing the infection to their baby. However, some women decline screening, even those who are interested in vaginal seeding, Pereira said. "(In those cases) there's a concern of taking group b strep from the birth canal and wiping it all over the baby," he added. In addition to bacterial infections, experts worry vaginal seeding could infect babies with herpes virus if the mother has genital herpes.
While it is true that vaginal seeding probably only exposes babies to the same pathogens they would have gotten had they been delivered vaginally, these pathogens could have been avoided by C-section delivery. "If they had [a C-section] because it was the way they had to be delivered for the safety of the baby or the mother, why would you want to impose on them an increased risk of infection if it's not going to benefit them?" Cunnington said.
While doctors might not be doing a lot of vaginal seeding themselves, some mothers are taking the matter into their own hands. In one report, a woman in Brooklyn planned to insert a piece of gauze in her vagina before her C-section operation that her husband would wipe on their newborn shortly after delivery. Although there are no guidelines for how to perform vaginal seeding, the studies of the practice generally insert the gauze one hour before delivery and then wipe the fluids around the baby's mouth, face and body.
It is important to tell these mothers that seeding might not have any benefit and might be increasing the risk of infection, Cunnington said. If they still want to do it, "They just need to be very aware that if their baby is unwell and they go to see a doctor, they should tell them they have performed vaginal seeding because it may change the doctor's assessment," he said. For example, a doctor may otherwise have ruled out the likelihood of a group B strep infection knowing that the baby was delivered via C-section.
Even though there is little evidence so far, it is also too soon to close the book on vaginal seeding. A small study recently provided the first evidence the practice might be able to give babies gut microbiomes that more closely resemble those of vaginally delivered infants.
However, "even if you can show their gut is colonized preferentially with labtobacillus or other organisms if you do that swab, you don't really know if that really has any clinical health benefits, or if in a year from now that really matters," Pereira said. More studies are needed, following babies who received vaginal seeding for years, to answer that question.
"It's a fascinating area of research and it holds a lot of promise," said David Hackney, assistant professor and medical director of labor and delivery at University Hospitals Case Medical Center.
"If someone said to me 10 to 15 years down the road this would be a routine thing we'll be doing, that would be great and I don't even know that I'd be surprised. But you can also imagine that in 10 to 15 years, we'll look back and say what is that crazy thing we were doing," Hackney said.
Until we have more answers about vaginal seeding, the potential for passing along healthy bacteria from the birth canal -- while treating women to avoid passing along disease-causing bugs -- could be just one more reason to encourage vaginal deliveries, Hackney said. C-sections are known to increase the risk of complications for both mother and baby, and increase the recovery time for the mothers.
And while vaginal seeding might not be ready for prime time just yet, there are other well-studied practices that could help ensure babies start life with a healthy microbiome. Breastfeeding and skin-to-skin contact between mother and baby are known to "help newborns be colonized with healthy bacteria pretty quickly," Pereira said.