[motoboi]

The microbiota is passed from mother to son on birth, not totally from the environment.

What we currently don’t understand is why for some people they never got them (we have techniques to transport the biota from the mother during birth for non-natural procedures) or they loose them.

Even with the transplant, the microbes won’t stick around on those people (not taking about autistic people here, but people in general).

Diverse food really helps, just as not eating ultraprocessed (they won’t reach the end of the intestines).

Fermented and other pre or probiotics will really help too.

But none of those will recover the biota in some people.

[jwrallie]

In some countries the number of kids born through c-section are very high, more than half the kids in Brazil are born that way for example, so definitely people can be healthy without getting it from their mothers.

[mejutoco]

I read it is a practice these days to do this fecal "rub" for newborns as a way to compensate for the C-section lack of it. I do not know if it happens in Brazil. Another factor to consider.

[giarc]

I've never heard of moms doing fecal rubs, but I've heard of many that do vaginal "transplants". I work in a hospital and we get questions quite a bit, moms will often take moist, sterile gauze and conduct the transplant themselves (staff can't really be involved for liability issues).

[mejutoco]

I just saw it in some documentary, but do not remember where. I found these, which look like what I heard described. I believe it is the same you mention:

https://pmc.ncbi.nlm.nih.gov/articles/PMC11095576/

https://www.nature.com/articles/d41586-024-03449-4

[neves]

It's not

[47282847]

> can be healthy

Or can they.

It’s (meant to be) an emergency procedure. Benefits: life. Downsides: plenty.

Maybe most relevant in the context of this thread:

“In this systematic review and meta-analysis of 61 studies comprising more than 20 million deliveries, birth by cesarean delivery was significantly associated with autism spectrum disorder and attention-deficit/hyperactivity disorder.“

Zhang, T., Sidorchuk, A., Sevilla-Cermeño, L., Vilaplana-Pérez, A., Chang, Z., Larsson, H., Mataix-Cols, D., Fernández de la Cruz, L., & D’Onofrio, B. M. (2019). Association of cesarean delivery with risk of neurodevelopmental and psychiatric disorders in the offspring: A systematic review and meta-analysis. JAMA Network Open, 2(8), e1910236. https://doi.org/10.1001/jamanetworkopen.2019.10236

A selection of some more:

Keag, O. E., Norman, J. E., & Stock, S. J. (2018). Long-term risks and benefits associated with cesarean delivery for mother, baby, and subsequent pregnancies: Systematic review and meta-analysis. PLOS Medicine, 15(1), e1002494. https://doi.org/10.1371/journal.pmed.1002494

De Mucio, B., Serruya, S., Alemán, A., Castellano, G., & Sosa, C. G. (2019). A systematic review and meta-analysis of cesarean delivery and other uterine surgery as risk factors for placenta accreta. International Journal of Gynecology & Obstetrics, 147(3), 281–291. https://doi.org/10.1002/ijgo.12948

Sandall, J., Tribe, R. M., Avery, L., Mola, G., Visser, G. H. A., Homer, C. S. E., Gibbons, D., Kelly, N. M., Kennedy, H. P., Kidanto, H., Taylor, P., & Temmerman, M. (2018). Short-term and long-term effects of caesarean section on the health of women and children. The Lancet, 392(10155), 1349–1357. https://doi.org/10.1016/S0140-6736(18)31930-5

Li, H.-T., Zhou, Y.-B., & Liu, J.-M. (2013). The impact of cesarean section on offspring overweight and obesity: A systematic review and meta-analysis. International Journal of Obesity, 37(7), 893–899. https://doi.org/10.1038/ijo.2012.195

S., Fleming, J., Bromley, A., Shields, M. D., & Cardwell, C. R. (2008). A meta-analysis of the association between Caesarean section and childhood asthma. Clinical & Experimental Allergy, 38(4), 629–633. https://doi.org/10.1111/j.1365-2222.2007.02780.x

Mascarello, K. C., Horta, B. L., & Silveira, M. F. (2017). Maternal complications and cesarean section without indication: Systematic review and meta-analysis. Revista de Saúde Pública, 51, 105. https://doi.org/10.11606/S1518-8787.2017051000389

[c-oreills]

Regarding the first study: follow up from the same authors overturns their own results: https://pubmed.ncbi.nlm.nih.gov/33666663/

> Conclusions and relevance: The findings of this study suggest that the association between CD and increased risk of neurodevelopmental disorders in the children was most likely explained by unmeasured familial confounding.