Table 1.

Characteristics of the study participants by diagnostic group.

Characteristics a	All children	ASD (n = 57)		TD (n = 116)		p-value b
	n	n	%	n	%
Child’s sex						0.04
Female	71	17	29.8	54	46.6
Male	102	40	70.2	62	53.4
Child’s birth year						0.53
2009-2010	61	19	33.3	42	36.2
2011-2013	57	22	38.6	35	30.2
2014-2015	55	16	28.1	39	33.6
Gestational age at delivery						0.37
≤ 37 weeks	10	2	3.5	8	6.9
> 37 weeks	163	55	96.5	108	93.1
Maternal age at delivery						0.91
< 35 years	93	31	54.4	62	53.4
≥ 35 years	80	26	45.6	54	46.6
Maternal BMI at pre-pregnancy						0.37
Normal/underweight	83	23	40.4	60	51.7
Overweight	50	19	33.3	31	26.7
Obese	40	15	26.3	25	21.6
Gestational diabetes						0.56
Yes	32	12	21.1	20	17.2
No	140	45	78.9	95	81.9
Maternal race/ethnicity						0.95
Non-Hispanic white	94	30	52.6	64	55.2
Hispanic	41	14	24.6	27	23.3
Other c	38	13	22.8	25	21.6
Maternal education						0.09
High school, some college	90	36	63.2	54	46.6
Bachelor’s degree	50	11	19.3	39	33.6
Graduate or professional	33	10	17.5	23	19.8
Homeownership						0.11
Yes	96	26	45.6	70	60.3
No	75	29	50.9	46	39.7
Parity						0.52
0	2	0	0.0	2	1.7
1	70	21	36.8	49	42.2
> 1	99	34	59.6	65	56.0
Maternal vitamin intake in the first month of pregnancy						0.07
Yes	88	23	40.4	65	56.0
No	84	33	57.9	51	44.0
Breastfeeding duration (months)		Mean (SD) 11.5 (10.3)		Mean (SD) 11.7 (9.5)		0.61

^aMissing information (n): gestational diabetes (1), homeownership (2), parity (2), maternal vitamin intake in the first month of pregnancy (1), breastfeeding duration (10).

^bP-value from the Pearson’s chi-squared test for categorical variables and the Mann-Whitney test for continuous variables.

^cIncludes Black/African American (3%), Asian (16%), and multiracial (3%).