Association of glucose levels in pregnancy with use of health care services

To determine whether women with abnormal gestational diabetes (GDM) screening test results short of frank GDM have increased health-services utilization compared to women with normal results. We conducted a retrospective-cohort study among 29,999 women enrolled in Kaiser Permanente Northwest who completed GDM screening (two-step method: 1-h, 50-g glucose-challenge test (GCT); 3-h, 100-g oral-glucose-tolerance test (OGTT)). Test results were categorized as normal GCT (referent, n = 25,535), normal OGTT (n = 2246), abnormal OGTT but not GDM (n = 1477), and GDM (n = 741). Rate ratios (RRs) were calculated for utilization measures and analyses were age- and BMI-adjusted. Compared to women with normal GCT, rates for obstetrical ultrasound, noninvasive and invasive antenatal testing, and ambulatory visits to the obstetrics department were significantly greater among women with abnormal OGTT (RRs 1.2 [95%CI 1.1, 1.4], 1.3 [1.1, 1.4], 1.7 [1.3, 2.3], and 1.1 [1.1, 1.1], respectively) and GDM (RRs 1.8, 1.8, 2.0, and 1.3, respectively). Women with abnormal OGTT results were more likely to visit a dietician than women with normal GCT; RRs ranged from 4.0 [3.3, 4.9] for women with abnormal GCT but normal OGTT to 72.1 [64, 81] for women with GDM. Health-services utilization increased with severity of glucose result, even among women without GDM.