Table 1.
Characteristics among women with GDM and their matched controls, the NICHD Fetal Growth Study-Singletons cohort
| GDM cases | Controls | P value* | |
| Age (years) | 30.5±5.7 | 30.4±5.4 | |
| Race/ethnicity | |||
| Non-Hispanic white | 25 (23.4) | 50 (23.4) | |
| Non-Hispanic black | 15 (14.0) | 30 (14.0) | |
| Hispanic | 41 (38.3) | 82 (38.3) | |
| Asian/Pacific Islander | 26 (24.3) | 52 (24.3) | |
| Education | 0.18 | ||
| Less than high school | 17 (15.9) | 26 (12.1) | |
| High school graduate or equivalent | 15 (14.0) | 23 (10.8) | |
| More than high school | 75 (70.1) | 165 (77.1) | |
| Insurance | |||
| Private or managed care | 68 (63.5) | 143 (66.8) | |
| Medicaid, self-pay, other | 39 (36.5) | 71 (33.2) | 0.50 |
| Marital status | |||
| Never married | 11 (10.3) | 35 (16.4) | |
| Married/living with a partner | 92 (86.0) | 167 (78.0) | |
| Divorced/separated | 4 (3.7) | 12 (5.6) | 0.12 |
| Nulliparity | 48 (44.9) | 96 (44.9) | 1.00 |
| Family history of diabetes | 40 (37.4) | 48 (22.4) | 0.001 |
| Prepregnancy BMI (kg/m2) |
28.2±6.4 | 25.6±5.3 | <0.001 |
| <25.0 | 37 (34.6) | 123 (58.0) | |
| 25.0–29.9 | 35 (32.7) | 56 (26.2) | |
| 30.0–34.9 | 20 (18.7) | 17 (7.9) | |
| 35.0–44.9 | 15 (14.0) | 16 (7.5) | |
| Unknown/missing | 2 (0.9) | <0.001 | |
| Smoking 6 months before pregnancy | 4 (3.7) | 1 (0.5) | 0.06 |
| Alcohol consumption 3 months before pregnancy | 61 (57.0) | 137 (64.0) | 0.22 |
Data are presented as n (%) for categorical variables and mean (SD) for continuous variables
*P values for differences between case and control subjects were obtained by mixed-effect linear regression models for continuous variables and binomial/multinomial logistic regression with generalized estimating equations for binary/multilevel categorical variables, accounting for matched case-control pairs. P values are not shown for matching variables (age and race/ethnicity).
BMI, body mass index; GDM, gestational diabetes mellitus; NICHD, National Institute of Child Health and Human Development.