Longitudinal Changes in Plasma Glucose Values of the 75-g Glucose Tolerance Test in Triplet Pregnancies

We evaluated longitudinal changing patterns of 75g glucose tolerance test (GTT) in triplet pregnancies. Eight triplet pregnancies were prospectively studied. All triplet pregnancies were fertilized with artificial reproductive techniques; patients showed no glucosuria or fasting hyperglycemia >100 mg/dL before pregnancy. The 75-g GTT was performed at first, second, and third trimester, as well as at postpartum. Longitudinal changes in glucose levels at fasting, 1 hour, and 2 hours were compared by one-way repeated-measure analysis of variance (ANOVA) and Bonferroni/Dunn test (p < 0.05). Values were expressed as mean ± standard deviation. Each of the 3-point values of 75-g GTT decreased after 28 weeks of gestation in triplet pregnancies. During the third trimester, fasting values were significantly decreased compared with postpartum values (65.5 ± 13.4 versus 74.6 ± 4.0 mg/dL), and 2-hour values were significantly decreased from those of second-trimester 75-g GTT (116.3 ± 19.5 versus 99.6 ± 17.1 mg/dL). Longitudinal glucose values of 75-g GTT improve during third trimester in triplet pregnancies, suggesting that fetoplacental fuel drain may counterbalance maternal insulin resistance.

KEYWORDS

Gestational diabetes mellitus - glucose tolerance test - triplet pregnancy

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