<p><i>Objective</i>: To investigate the influence of medical nutrition therapy (MNT) on borderline glucose intolerance (BGI) in pregnant Taiwanese women.</p> <p><i>Methods</i>: A total of 5194 singleton pregnant women were enrolled in this prospective, non-randomized study. The participants were subjected to the 50 g 1-h glucose challenge test (GCT) and 100 g 3-h oral glucose tolerance test (OGTT) to screening gestational diabetes mellitus (GDM). BGI was defined as a positive GCT and normal OGTT results. GDM was defined as a positive GCT and abnormal OGTT results. The women were categorized into the following groups: (1) GCT-negative, <i>n</i> = 3881; (2) BGI with MNT, <i>n</i> = 273; (3) BGI without MNT, <i>n</i> = 712; and (4) GDM, <i>n</i> = 328. Multiple logistic analyses were used to estimate the risks of pregnancy outcomes.</p> <p><i>Results</i>: The odds ratios (95% confidence interval) for total cesareans, third- or fourth-degree perineal lacerations, gestational hypertension or preeclampsia and macrosomia were 1.24 (1.04–1.49), 1.55 (1.06–1.28), 1.78 (1.21–2.61) and 2.50 (1.28–4.91) in the BGI without MNT group compared to the GCT-negative group. There was no difference between BGI with MNT and GCT-negative groups.</p> <p><i>Conclusions</i>: Women with BGI who did not receive MNT had increased risks of adverse pregnancy outcomes, whereas who received MNT had no different risk with GCT-negative women.</p
