Table 1.

Sample characteristics (n = 171).

	n	%	Mean (SD)
Infant sex
Female	87	50.9
Male	84	49.1
Maternal race/ethnicity
African-American	84	49.1
Latina	87	50.9
Plurality
Singleton	146	85.4
Twin or triplet	25	14.6
Type of delivery
Vaginal	89	52.4
C-section	81	47.6
Clinical site
A	97	56.7
B	74	43.3
Postmenstrual age (PMA) at baseline feeding observation (weeks)
32	18	10.5
33	36	21.1
34	62	36.3
35–36	55	32.2
Gestational age at birth	171		32.6 (1.5)
Birth weight (g)	171		1812 (355)
Apgar score at 5 min	170		8.3 (1.0)
Morbidity score (POPRAS)	165		68.2 (18.9)
Weight at baseline (g)	166		1852 (293)