Pregnancy and child

C-section mums warned about dangers of ‘vaginal seeding’

What is the issue?

A technique called vaginal seeding, sometimes used for babies born by caesarean section, "can give newborns deadly infections and sepsis," warns the Mail Online.

Vaginal seeding involves rubbing vaginal fluid onto the skin of a newborn baby born by caesarean section. It's intended to mimic the natural transfer of microbes from their mother that babies have during a vaginal birth. This has been reported by some to help boost a baby's response against allergies and asthma.

As many as 90% of Danish obstetricians and gynaecologists said they have been asked about it by prospective parents. Despite this, there has been very little research into the technique and its safety has been questioned.

Why is vaginal seeding in the news now?

The Danish Society for Obstetrics and Gynaecology set up a group of doctors to review evidence and produce a guideline on vaginal seeding. The group has published a commentary on their guideline in the peer reviewedBritish Journal of Obstetrics and Gynaecology.

BBC News and Mail Online both carried reasonably balanced and accurate reports of the commentary. The Mail Online headline was over-stated, as there's no evidence that babies have been subjected to "deadly infections" in this way; only the risk that it might happen.

What is vaginal seeding and why is it done?

Vaginal seeding was developed to mimic microbial transfer during birth. Gauze swabs are placed in the mother's vagina, then after the caesarean birth, rubbed onto the baby's face and body.

Babies born by caesarean are slightly more at risk of some inflammatory diseases including asthma and allergies. Some scientists think that the lack of maternal microbes transferred during a vaginal birth might be the reason for this increased risk. They believe caesarean section may affect the development of a child's normal population of microbes.

It's an interesting hypothesis, but has only been tested on four babies in an exploratory trial. All the mothers in the study were screened for potentially harmful microbes before their newborn babies were given vaginal seeding. However, as the Danish group points out, there isn't much evidence to decide which microbes to screen for.

Because there's been so little research, we don't know whether the technique is safe or effective. The one study that has been conducted was only intended to explore the theory of microbial transfer, not to look at safety.

What are the risks of vaginal seeding?

The main risk is that babies might get serious infections. Early onset neonatal sepsis – a serious infection more common in preterm babies – can be caused by transfer of bacteria including E. coli and Group B streptococcus from the mother during vaginal birth.

Last year we reported that doctors from Australia and the UK warned against vaginal seeding in an opinion piece in the British Medical Journal (BMJ), because of the infection risk.

The Danish group said the risk is "probably very low" but that "at this point in time, there is no evidence to suggest that the proposed long-term benefits would outweigh the costs and potential risks."

They say parents should be told that the research so far is exploratory, that the risks are unknown, and that other activities – such as breastfeeding – are "more important" ways to help babies establish a healthy microbial population.

What are the conclusions?

The advice from Danish doctors echoes that of the UK and Australian doctors we reported last year: vaginal seeding has unknown risks and is not recommended.

The Danish group says it "strongly recommends against" use of the technique in preterm babies, because of the increased risk of sepsis.

However, parents who are concerned about giving their baby the best start after a caesarean section can try other, more established techniques.

Skin-to-skin contact with the mother shortly after birth can help bonding – and possibly microbial transfer – and can also encourage early breastfeeding.

Breastfeeding is thought to be a good way to ensure transfer of the microbes a baby needs in the early months of life.

Read more about the benefits of breastfeeding.

NHS Attribution