Bacteria in the mother’s birth canal can help the nervous system development of a C-section baby

Babies born by caesarean section are left without the microbes to which the baby is exposed during vaginal delivery. It has already been known that C-section babies may have a higher risk of immune system and metabolic disorders due to a lack of microbes.

Published three years ago by a Chinese research group randomized trial showed that the bacteria in the mother’s birth canal also support the development of the nervous system and brain.

Now the team shows a possible mechanism: bacteria in the vagina produce a compound that affects the brain on the newborn’s skin.

Previously it has been thought that the bacteria obtained during vaginal delivery affect the child’s development mainly through the intestines.

Researcher in pharmacology Zhang Yuhang However, Peking University found that although the bacteria transferred from the mother’s vaginal fluid did not remain in the baby’s gut for a long time, the babies still showed a small but statistically significant developmental step at six months of age.

“It made us suspect that the phenomenon cannot be explained solely by the gut,” says Zhang in Science magazine.

This made the research team interested in the skin.

When researchers massaged babies born by caesarean section with vaginal microbes, more of a certain molecule appeared on the baby’s skin. The more of it, the better they were baby’s early development descriptive scores at three and six months of age.

Based on surveys completed by the parents, babies who received birth canal microbes appeared to be slightly further along in motor skills and communication than other babies born by caesarean section.

Now was observed in mouse experimentsthat the compound produced on the skin was transported to the brain. The compound appeared to activate messages in the brain that help neurons mature and form functional connections at the right time.

In mice, this was reflected in the fact that chicks born by caesarean section initially developed slower in their movements than those born by caesarean section. When a lab-made version of this compound was applied to their skin, the chicks caught up and got closer to the others in development.

From mom the transfer of the obtained microbes and the substances they produce to babies is not yet a complete treatment. So far, microbial transfer is only done in carefully controlled studies.

It is not yet known with sufficient certainty who benefits from the transplants, how big the benefit is, and whether the method is widely safe. The biggest concern is the transfer of possible infections from mother to baby.

An answer is expected from the ongoing larger studies, especially on whether the transfer of the mother’s bacteria to the baby is beneficial for allergies, for example.