Table 1.

Demographic characteristics

Characteristic	Controls (N = 195)	Cases (N = 18)	P-value
Maternal age (years)	33.0 (±6.9)	31.4 (7.3)	0.348
Gestational age (weeks)a	14.3 (±2.65)	15.1 (3.13)	0.277
Race/Ethnicity			0.072
White	114 (59%)	5 (28%)
Black	34 (17%)	5 (28%)
Hispanic	18 (9%)	4 (22%)
Other	29 (15%)	4 (22%)
Maternal weight (pounds)	155.2 (±37.7)	165.3 (56.7)	0.300
Primagravida	45 (23%)	1 (6%)	0.084
Nulliparous	79 (41%)	4 (22%)	0.128
Current Smoker	30 (16%)	2 (11%)	0.622
Uninsured	15 (8%)	2 (11%)	0.865
Abnormal serum screen	124 (65%)	15 (83%)	0.120

Results are presented as mean (±standard deviation) or n (%)

^aGestational age at the time of serum screening