April - June 2009, Volume 5, Issue 2

Sarac F, Tutuncuoglu P, Tavmergen E, Saygili F, Ozgen AG, Tuzun M

Glucose tolerance tests in the singleton and twin pregnancy

Acta Endo (Buc) 2009, 5 (2): 183-189
doi: 10.4183/aeb.2009.183

Objective. Gestational diabetes mellitus (GDM) is defined as glucose intolerance that\r\nis detected for the first time during pregnancy. Normal pregnancy induces insulin resistance\r\nthrough the diabetogenic effects of placental hormones. Glucose tolerance test results in\r\ntwin and singleton pregnancies were compared in this study.\r\nSubjects and Methods. A total of 360 pregnant women were studied. 200 women\r\n(mean age 31.60?2.10 yr) had singleton pregnancies (Group I) and 160 women (mean age\r\n28.20?2.70 yr) had twin pregnancies (Group II). 50- g, 1- hour glucose tolerance test was\r\nconducted on the first prenatal visit. An abnormal glucose screen defined as glucose > 140\r\nmg/dL was followed by a 100g, 3-hour glucose tolerance test. Gestational diabetes was\r\ndefined as the presence of two or more abnormal values during the 3-hour test.\r\nResults. Gestational diabetes was found in 4 of the 200 (2%) singleton pregnant\r\nwomen and 8 of the 160 (5%) twin pregnant women. Group I (Singleton) was further\r\ndivided into two subgroups according to whether the 1-hr plasma glucose level was < 140\r\nmg/dl (Group Ia) or >140 mg/dL (Group Ib). Likewise, Group II pregnancies was also\r\ndivided into two subgoups on the same basis. Mean screening test glucose levels were found\r\nto be 127.8?14.94 mg/dL in Group Ia and 150.8 ? 18.1 mg/dL in Group Ib women. Mean\r\nscreening test glucose levels of Group IIa subjects was 92.80 ? 18.30 mg/dL while that of\r\nGroup IIb subjects was 154.8 ? 27.0 mg/dL. Mean 1st h glucose levels of 100-g glucose\r\ntolerance test was found to be 131.4 ? 32.58 mg/dL in Group I, and 112.5 ? 39.6 mg/dL in\r\nGroup II. Mean 2nd h glucose tolerance test values were 133.2 ? 28.8 mg/dL in Group I and\r\n100.6?28.8 mg/dL in Group II. Mean 3rd h glucose tolerance test values were 107.6 ? 23.58\r\nmg/dl in Group I and 72?16.9 mg/dL in Group II.\r\nConclusion: Glucose screening results and 100-g, 3- hour glucose tolerance test\r\nvalues have been found to be lower in twin pregnancies than in singleton pregnancies.\r\nTherefore, we suggest that these findings be taken into account in developing diagnostic\r\ncriteria for gestational diabetes in twin or more pregnancies.

Keywords: gestational diabetes, glucose tolerance, twin pregnancy, singleton pregnancy

Correspondence: Fulden Sara?, M.D., Ege University Hospital, Department of Endocrinology\r\nand Metabolism, Bornova, Izmir, 35100, Turkey, E mail: fuldensarac@yahoo.com Fax: 90 232\r\n3737701, Tel: 90 232 3737701