Table 1.
Distributions of clinical and sociocultural characteristics overall and by race. Continuous variables are reported as median (interquartile range) and categorical variables are reported as n (%).
| Clinical and demographic variables | Overall (n = 378) | African American (n = 186) | Caucasian (n = 192) | p-value |
|---|---|---|---|---|
| Age, yearsa, i | 27.0 (8) | 24.0 (8) | 29.0 (7.5) | <0.001 |
| BMI, kg/m2 b, i | 27.2 (8.5) | 29.4 (9.8) | 26.3 (6.4) | <0.001 |
| Nulliparousc, j | 153 (40.7) | 60 (32.1) | 93 (48.9) | <0.001 |
| Ever smokerd, j | 44 (11.7) | 23 (12.4) | 21 (11.1) | 0.69 |
| Used medication during pregnancye, j | 144 (40.0) | 67 (38.1) | 77 (41.8) | 0.46 |
| Used prenatal vitamins during pregnancyf, j | 316 (88.3) | 148 (84.6) | 168 (91.8) | 0.03 |
| Used contraception before pregnancyf, j | 68 (19.0) | 26 (14.9) | 42 (22.8) | 0.06 |
| Married or living as marriedg, j | 197 (54.9) | 44 (25.1) | 153 (83.2) | <0.001 |
| Educationf, k | ||||
| < High School | 40 (11.2) | 28 (16.1) | 12 (6.5) | <0.001 |
| High School | 75 (20.9) | 57 (32.8) | 18 (9.8) | |
| Some college | 88 (24.6) | 51 (29.3) | 37 (20.1) | |
| College + | 155 (43.3) | 38 (21.8) | 117 (63.6) | |
| Household incomeh, k | ||||
| < $25 000 | 90 (25.4) | 70 (40.2) | 20 (11.0) | 0.03 |
| $25 000 e $65 000 | 81 (22.8) | 32 (18.4) | 49 (27.1) | |
| > $65 000 | 89 (25.1) | 5 (2.9) | 84 (46.4) | |
| Don’t know | 95 (26.8) | 67 (38.5) | 28 (15.5) | |
| Season of enrollmentk | ||||
| Spring | 88 (23.3) | 46 (24.7) | 42 (21.9) | 0.66 |
| Summer | 124 (32.8) | 64 (34.2) | 60 (31.3) | |
| Fall | 97 (25.7) | 43 (23.0) | 54 (28.1) | |
| Winter | 69 (18.2) | 33 (17.6) | 36 (18.8) | |
| Year of enrollmentk | ||||
| 2011 | 77 (20.4) | 39 (21.0) | 38 (19.8) | 0.80 |
| 2012 | 122 (32.3) | 60 (32.3) | 62 (32.3) | |
| 2013 | 113 (29.9) | 58 (31.2) | 55 (28.6) | |
| 2014 | 66 (17.5) | 29 (15.5) | 37 (19.3) |
Characters represent missing observations.
a
n = 1.
b
n = 3.
c
n = 2.
d
n = 4.
e
n = 19.
f
n = 21.
g
n = 20.
h
n = 24.
i
Mann-Whitney U test for difference by race.
j
Chi-square test for difference by race.
k
Cochran-Armitage trend test for difference by race.