Table 1

Characteristics among women with GDM and their matched controls, the NICHD Fetal Growth Study-Singletons cohort

GDM casesControlsP value*
Age (years)30.5±5.730.4±5.4
Race/ethnicity
 Non-Hispanic white25 (23.4)50 (23.4)
 Non-Hispanic black15 (14.0)30 (14.0)
 Hispanic41 (38.3)82 (38.3)
 Asian/Pacific Islander26 (24.3)52 (24.3)
Education0.18
 Less than high school17 (15.9)26 (12.1)
 High school graduate or equivalent15 (14.0)23 (10.8)
 More than high school75 (70.1)165 (77.1)
Insurance
 Private or managed care68 (63.5)143 (66.8)
 Medicaid, self-pay, other39 (36.5)71 (33.2)0.50
Marital status
 Never married11 (10.3)35 (16.4)
 Married/living with a partner92 (86.0)167 (78.0)
 Divorced/separated4 (3.7)12 (5.6)0.12
Nulliparity48 (44.9)96 (44.9)1.00
Family history of diabetes40 (37.4)48 (22.4)0.001
Prepregnancy BMI
(kg/m2)
28.2±6.425.6±5.3<0.001
 <25.037 (34.6)123 (58.0)
 25.0–29.935 (32.7)56 (26.2)
 30.0–34.920 (18.7)17 (7.9)
 35.0–44.915 (14.0)16 (7.5)
 Unknown/missing2 (0.9)<0.001
Smoking 6 months before pregnancy4 (3.7)1 (0.5)0.06
Alcohol consumption 3 months before pregnancy61 (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.