Table 2.

Associations between maternal body composition and human milk bacterial OTU relative abundance.

Maternal Predictor	Secretor			Non-Secretor			Interaction
	Parameter Estimate	SE	p-Value	Parameter Estimate	SE	p-Value	p-Value
	OTU03 (Streptococcus salivarius)
Log (Weight (kg))	−2.24	0.82	0.01	6.01	5.07	0.24	0.12
Log (BMI (kg/m2))	−2.52	0.89	0.01	4.44	2.8	0.12	0.02
Log (FM (kg))	−1.37	0.5	0.01	2.63	2	0.19	0.06
FM (%)	−0.06	0.03	0.04	0.12	0.08	0.17	0.05
Log (FMI (kg/m2))	−1.42	0.52	0.01	2.25	1.51	0.14	0.02
Log (FM/FFM)	−1.33	0.64	0.04	2.66	1.96	0.18	0.06
	OTU06 (Streptococcus lactarius)
Age	0.03	0.04	0.41	0.82	0.26	<0.001	<0.001
	OTU08 (Gemella haemolysans)
Log (BMI (kg/m2))	−0.69	1.28	0.59	5.43	2.39	0.03	0.03
FFMI (kg/m2)	−0.05	0.11	0.64	0.55	0.24	0.03	0.03
Log (FMI (kg/m2))	−0.37	0.74	0.62	2.62	1.22	0.04	0.04
	OTU10 (Veillonella nakazawae)
FFMI (kg/m2)	0.12	0.06	0.04	0.42	0.19	0.03	0.14
	Entire cohort
	OUT01 (Streptococcus mitis)
Age	0.07	0.03	0.04	-	-	-	-
	OTU02 (Staphylococcus epidermidis)
Log (Weight (kg))	−1.54	0.69	0.03	-	-	-	-
FFM (kg)	−0.04	0.02	0.02	-	-	-	-
Log (FM (kg))	−1.04	0.43	0.02	-	-	-	-
Log (FMI (kg/m2))	−0.9	0.43	0.04	-	-	-	-
	OTU10 (Veillonella nakazawae)
FFM (kg)	0.04	0.02	0.03	-	-	-	-

Data are parameter value ± standard error of measurement (SE); note that these estimates are on the logit scale. When the interaction term with secretor status was present in the final model, results were separated by secretor and non-secretor groups, whereas when the interaction term was not present in the final model, results were presented for the entire cohort. Significant p-values are indicated by the bold text. BMI—body mass index; ECS—emergency caesarean section; FFM—fat-free mass; FFMI—fat-free mass index; FM—fat mass; FM/FFM—fat mass to fat-free mass ratio; FMI—fat mass index; MOD—mode of delivery.