Maternal and Infant Skin Microbiomes Show Distinct but Connected Development

The skin microbiomes of mothers and their infants appear to be closely connected during early life, although infant microbial diversity follows its own developmental trajectory, according to a recent longitudinal study published in Experimental Dermatology.

Researchers for the study followed women from pregnancy through 6 months postpartum and their infants from 4 weeks through 6 months of age to characterize changes in skin microbial ecology and examine potential mother-infant associations. The study enrolled 109 pregnant women with 93 mother-infant pairs completing follow-up. The researchers collected skin microbiome samples from the volar forearm, with investigators assessing bacterial composition, species richness, and microbial diversity.

The maternal skin microbiome demonstrated mild to moderate changes throughout pregnancy and the first 6 months after childbirth. More pronounced development occurred among infants. Mean infant species richness increased significantly from 82.6 at 4 weeks to 116.1 at 6 months. Despite this increase, infant skin microbial diversity remained below maternal levels, with mothers reaching a mean species richness of 145.4 at 6 months postpartum. The researchers also identified evidence of maternal-infant skin microbiome synchrony. Microbial similarity within individual mother-infant pairs was consistently and significantly greater than similarity between unrelated mothers and infants at both assessed time points.

The authors said the findings indicate infant skin microbiome becomes progressively more diverse during the first 6 months of life while maintaining a distinct microbial relationship with the mother's skin microbiome. 

Source

Wilborn D, et al. Experimental Dermatology. 2026. Doi:10.1111/exd.70349