Table 4:
Richness and diversity of fecal microbiota in infants, by early-life exposures
| Exposure | No. of infants | Richness score,* mean ± SD | p value† | Diversity index,* mean ± SD | p value† |
|---|---|---|---|---|---|
| Overall | 24 | 12.0 ± 5.0 | 1.38 ± 0.53 | ||
| Sex | |||||
| Female | 12 | 12.1 ± 5.0 | 0.9 | 1.37 ± 0.53 | 0.9 |
| Male | 12 | 11.9 ± 5.1 | 1.40 ± 0.56 | ||
| Mode of delivery | |||||
| Vaginal | 18 | 11.2 ± 4.4 | 0.007 | 1.33 ± 0.49 | 0.06 |
| Emergency cesarean | 3 | 19.7 ± 3.2 | 2.02 ± 0.48 | ||
| Elective cesarean | 3 | 9.3 ± 1.5 | 1.09 ± 0.47 | ||
| Receipt of antibiotics | |||||
| No | 19 | 11.5 ± 4.9 | 0.8 | 1.34 ± 0.55 | 0.6 |
| Yes | 3 | 10.7 ± 3.8 | 1.52 ± 0.53 | ||
| At 2 d (infant D) | 1 | 15 | 1.99 | ||
| At 6 wk (infant U) | 1 | 9 | 0.95 | ||
| At 3 mo (infant X) | 1 | 8 | 1.62 | ||
| Diet at 4 mo | |||||
| Exclusively breastfed | 10 | 9.0 ± 4.1 | 0.006 | 1.19 ± 0.51 | 0.1 |
| Partially breastfed | 5 | 12.6 ± 5.3 | 1.42 ± 0.64 | ||
| Not breastfed | 9 | 15.0 ± 4.0 | 1.58 ± 0.47 |
Note: SD = standard deviation.
*
Richness was measured with the Chao1 score, which estimates the number of different species present. Diversity was measured with the Shannon diversity index, which evaluates both the number of species and the evenness of their distribution.
†
Two-tailed Student t-test or analysis of variance, with trend test for diet groups.