RESUMEN
OBJECTIVE: In most gestational diabetes mellitus (GDM) studies, cohorts have included women combined into study populations without regard to whether hyperglycemia was present earlier in pregnancy. In this study we sought to compare perinatal outcomes between groups: women with early GDM (EGDM group: diagnosis before 20 weeks but no treatment until 24-28 weeks if GDM still present), with late GDM (LGDM group: present only at 24-28 weeks), and with normoglycemia at 24-28 weeks (control subjects). RESEARCH DESIGN AND METHODS: This is a secondary analysis of a randomized controlled treatment trial where we studied, among women with risk factors, early (<20 weeks' gestation) GDM defined according to World Health Organization 2013 criteria. Those receiving early treatment for GDM treatment were excluded. GDM was treated if present at 24-28 weeks. The primary outcome was a composite of birth before 37 weeks' gestation, birth weight ≥4,500 g, birth trauma, neonatal respiratory distress, phototherapy, stillbirth/neonatal death, and shoulder dystocia. Comparisons included adjustment for age, ethnicity, BMI, site, smoking, primigravity, and education. RESULTS: Women with EGDM (n = 254) and LGDM (n = 467) had shorter pregnancy duration than control subjects (n = 2,339). BMI was lowest with LGDM. The composite was increased with EGDM (odds ratio [OR] 1.59, 95% CI 1.18-2.12)) but not LGDM (OR 1.19, 95% CI 0.94-1.50). Induction of labor was higher in both GDM groups. In comparisons with control subjects there were higher birth centile, higher preterm birth rate, and higher rate of neonatal jaundice for the EGDM group (but not the LGDM group). The greatest need for insulin and/or metformin was with EGDM. CONCLUSIONS: Adverse perinatal outcomes were increased with EGDM despite treatment from 24-28 weeks' gestation, suggesting the need to initiate treatment early, and more aggressively, to reduce the effects of exposure to the more severe maternal hyperglycemia from early pregnancy.
RESUMEN
BACKGROUND: Whether treatment of gestational diabetes before 20 weeks' gestation improves maternal and infant health is unclear. METHODS: We randomly assigned, in a 1:1 ratio, women between 4 weeks' and 19 weeks 6 days' gestation who had a risk factor for hyperglycemia and a diagnosis of gestational diabetes (World Health Organization 2013 criteria) to receive immediate treatment for gestational diabetes or deferred or no treatment, depending on the results of a repeat oral glucose-tolerance test [OGTT] at 24 to 28 weeks' gestation (control). The trial included three primary outcomes: a composite of adverse neonatal outcomes (birth at <37 weeks' gestation, birth trauma, birth weight of ≥4500 g, respiratory distress, phototherapy, stillbirth or neonatal death, or shoulder dystocia), pregnancy-related hypertension (preeclampsia, eclampsia, or gestational hypertension), and neonatal lean body mass. RESULTS: A total of 802 women underwent randomization; 406 were assigned to the immediate-treatment group and 396 to the control group; follow-up data were available for 793 women (98.9%). An initial OGTT was performed at a mean (±SD) gestation of 15.6±2.5 weeks. An adverse neonatal outcome event occurred in 94 of 378 women (24.9%) in the immediate-treatment group and in 113 of 370 women (30.5%) in the control group (adjusted risk difference, -5.6 percentage points; 95% confidence interval [CI], -10.1 to -1.2). Pregnancy-related hypertension occurred in 40 of 378 women (10.6%) in the immediate-treatment group and in 37 of 372 women (9.9%) in the control group (adjusted risk difference, 0.7 percentage points; 95% CI, -1.6 to 2.9). The mean neonatal lean body mass was 2.86 kg in the immediate-treatment group and 2.91 kg in the control group (adjusted mean difference, -0.04 kg; 95% CI, -0.09 to 0.02). No between-group differences were observed with respect to serious adverse events associated with screening and treatment. CONCLUSIONS: Immediate treatment of gestational diabetes before 20 weeks' gestation led to a modestly lower incidence of a composite of adverse neonatal outcomes than no immediate treatment; no material differences were observed for pregnancy-related hypertension or neonatal lean body mass. (Funded by the National Health and Medical Research Council and others; TOBOGM Australian New Zealand Clinical Trials Registry number, ACTRN12616000924459.).