Trends in postpartum diabetes screening and subsequent diabetes and impaired fasting glucose among women with histories of gestational diabetes mellitus: A report from the Translating Research Into Action for Diabetes (TRIAD) Study

OBJECTIVE—The purpose of this study was to examine trends in postpartum glucose screening for women with gestational diabetes mellitus (GDM), predictors of screening, trends in postpartum impaired fasting glucose (IFG) and diabetes, and diabetes and pre-diabetes detected by postpartum fasting plasma glucose (FPG) versus a 75-g oral glucose tolerance test (OGTT).RESEARCH DESIGN AND METHODS—This was a cohort study of 14,448 GDM pregnancies delivered between 1995 and 2006. Postpartum screening was defined as performance of either an FPG or OGTT at least 6 weeks after delivery and within 1 year of delivery.RESULTS—Between 1995 and 2006, the age- and race/ethnicity-adjusted proportion of women who were screened postpartum rose from 20.7% (95% CI 17.8–23.5) to 53.8% (51.3–56.3). Older age, Asian or Hispanic race/ethnicity, higher education, earlier GDM diagnosis, use of diabetes medications during pregnancy, and more provider contacts after delivery were independent predictors of postpartum screening. Obesity and higher parity were independently associated with lower screening performance. Among women who had postpartum screening, the age- and race/ethnicity-adjusted proportion of IFG did not change over time (24.2 [95% CI 20.0–27.8] in 1995–1997 to 24.3 [22.6–26.0] in 2004–2006), but the proportion of women with diabetes decreased from 6.1 (95% CI 4.2–8.1) in 1995–1997 to 3.3 (2.6–4.0) in 2004–2006. Among women who received an OGTT in 2006, 38% of the 204 women with either diabetes or pre-diabetes were identified only by the 2-h glucose measurements.CONCLUSIONS—Postpartum screening has increased over the last decade, but it is still suboptimal. Compared with FPGs alone, the 2-h values identify a higher proportion of women with diabetes or pre-diabetes amenable to intervention.Gestational diabetes mellitus (GDM) is defined as carbohydrate intolerance with onset of or first recognition during pregnancy. Postpartum diabetes screening may detect diabetes that preceded pregnancy and therefore enable early treatment of hyperglycemia, reducing the risk of adverse fetal outcomes in subsequent pregnancies (1) and maternal microvascular complications (2). Screening can also identify women who might benefit from diabetes prevention interventions (3,4).Performance rates of postpartum diabetes screening have been low (5–7), but screening performance may have changed recently. At present, only one population-based report has examined postpartum diabetes screening practices, and this report examined fasting plasma glucose (FPG) only (8). We used data from a GDM registry in a large prepaid group practice managed health care organization (the Kaiser Permanente Medical Care Program in Northern California [KPNC]) and examined 1) postpartum diabetes screening over time, 2) predictors of postpartum screening in a detailed electronic medical record, 3) trends in impaired fasting glucose (IFG) or diabetes detected with postpartum screening, and 4) the proportion of women with diabetes or pre-diabetes identified by the FPG screen versus the proportion of women with these abnormal glucose values identified by the 75-g oral glucose tolerance test (OGTT).