Table 1:

Characteristics of study cohort, overall and stratified by sex (N=101)

	Overall (N=101)	Males (N=51)	Females (N=50)
Insurance, N (%)
Medicaid	24 (23.8)	16 (31.4)	8 (16.0)
Private/Self pay	77 (76.2)	35 (68.6)	42 (84.0)
Race, N (%)
White (non-Hispanic)	48 (49.0)	19 (39.6)	29 (58.0)
Black (non-Hispanic)	25 (25.5)	10 (20.8)	15 (30.0)
Asian (non-Hispanic)	3 (3.0)	3 (6.3)	0 (0.0)
Hispanic	9 (9.2)	8 (16.7)	1 (2.0)
Mixed Race	4 (4.1)	2 (4.2)	2 (4.0)
Other	9 (9.2)	6 (12.5)	3 (6.0)
Missing	3	3	0
Small for gestational age (SGA), N (%)	11 (10.9)	9 (17.6)	2 (4.0)
NEC > stage I, N (%)	2 (2.0)	2 (3.9)	0 (0.0)
ROP stage, N (%)
0	89 (89.0)	42 (84.0)	47 (94.0)
1	2 (2.0)	1 (2.0)	1 (2.0)
2	8 (8.0)	6 (12.0)	2 (4.0)
3	1 (1.0)	1 (2.0)	0 (0.0)
Missing	1 (1.0)	1 (2.0)	0 (0.0)
IVH grade, N (%)
0	79 (78.2)	40 (78.4)	39 (78.0)
1	19 (18.8)	9 (17.3)	10 (20.0)
2	1 (1.0)	1 (2.0)	0 (0.0)
3	0 (0.0	0 (0.0)	0 (0.0)
4	2 (2.0)	1 (2.0)	1 (2.0)
Sepsis, N (%)	11 (10.9)	9 (17.7)	2 (4.0)
BPD, N (%)	17 (17.0)	10 (10.0)	7 (14.0)
Gestational age (weeks), Mean (SD)	30.0 (2.2)	29.8 (2.4)	30.3 (1.9)
Birth weight (grams), Mean (SD)	1326 (364)	1261 (380)	1393 (338)
Apgar score at 1 min, Median (IQR)	8 (2)	8 (3)	8 (2)
Apgar score at 5 min, Median (IQR)	9 (0)	9 (1)	9 (0)
Maternal age at delivery (years), Mean (SD)	32.7 (6.4)	31.3 (6.5)	34.2 (6.1)
Time to first growth spurt (weeks), Mean (SD)	33.5 (1.71)	33.5 (1.78)	33.4 (1.66)
Slope of first growth spurt (kg/week), Mean, (SD)	11.5 (36.9)	14.1 (46.1)	8.77 (24.5)
# of samples between birth and first growth spurt, Mean (SD)	2 (1.4)	2 (1.6)	2 (1.3)