Effectiveness of screening for gestational diabetes during the late gestational period among pregnant Turkish women

Abstract

Aim: To assess the incidence of gestational diabetes mellitus (GDM) beyond 30 gestational weeks (GW) in pregnant Turkish women and to determine the criteria for repeating the test during the late period of gestation when the results were normal after the initial screen.

Materials and methods: Two hundred pregnant women were enrolled. Maternal age, gravidity, parity and presence of other risk factors (family history of diabetes mellitus, habitual abortions, prior fetal macrosomia, obesity, gestational hypertension history) were collected. First, GDM was evaluated between the 24th and 28th GW by screening (50-g glucose challenge test) and diagnostic tests. This protocol was repeated again at least 1 month from the first screen at the 30th-34th GW in all patients, except those diagnosed with GDM due to an abnormal 3-h test. The results were compared with the clinical risk factors.

Results: In total, 19.5% of the cases had positive results in the first screening test. Six patients were diagnosed with GDM. Among the remaining 194 pregnancies, another 10 cases were diagnosed as having GDM with repeated tests, and the incidence of newly diagnosed GDM was 5.2%. Only the mean age (34.2 years) (P = 0.010) and a history of delivering a macrosomic infant (P < 0.010) were significantly high in the late-gestation GDM-positive cases.

Conclusions: Even when early screening tests are negative, pregnancies with advanced maternal ages and those with a history of delivering a macrosomic infant should be re-evaluated for GDM during the late gestational period with screening and diagnostic tests.