PREGNANCY OUTCOMES IN WOMEN WITH GESTATIONAL DIABETES COMPARED WITH THE GENERAL OBSTETRIC POPULATION

Objective: To compare pregnancy outcome in a homogeneous group of wome n with glucose intolerance with that of women without this disorder. M ethods: This was a retrospective cohort study of all women with single ton cephalic-presenting pregnancies delivered at University of Texas S outhwestern Medical Center during the period January 1, 1991, through December 31, 1995. During this period, women were screened selectively for glucose intolerance and National Diabetes Data Group thresholds w ere used to diagnose gestational diabetes. Women with class A(1) gesta tional diabetes were compared with nondiabetic women within the cohort . Effects of confounding variables were analyzed using multiple logist ic regression and a matched-control comparison. Controls were matched according to ethnicity, maternal age, maternal weight, and parity. Res ults: A total of 61,209 nondiabetic women with singleton cephalic preg nancies were delivered during the study period, and 874 were diagnosed with class A(1) gestational diabetes. Women with class A(1) gestation al diabetes were significantly older, heavier, of greater parity, and more often of Hispanic ethnicity. Hypertension (17 versus 12%), cesare an delivery (30 versus 17%), and shoulder dystocia (3 versus 1%) were significantly increased (all P < .001) in these women compared with th e general obstetric population. Infants born to women with class A(1) gestational diabetes were significantly larger (mean birth weight 3581 +/- 616 versus 3290 +/- 546 g, P < .001), and this accounted for the increased incidence of dystocia. The attributable risk for large for g estational age (LGA) infants due to class A(1) gestational diabetes wa s 12%. Conclusion: The main consequence of class A(1) gestational diab etes is excessive fetal size leading to increased risk of difficult la bor and delivery. We estimate that approximately one of eight women wi th class A(1) gestational diabetes mellitus delivers an LGA infant att ributable to glucose intolerance. (C) 1997 by The American College of Obstetricians and Gynecologists.