Association of maternal glucose and body mass index with adverse pregnancy outcomes among women with normal oral glucose tolerance test results

Abstract

Aims: The study aims to investigate whether adverse pregnancy outcomes were associated with different glucose and BMI levels, even among women with normal oral glucose tolerance test (OGTT) results.

Methods: This retrospective cohort study used data of 15,967 pregnant women who underwent a 75-g OGTT between 24 and 30 gestational weeks. Adverse pregnancy outcomes included cesarean delivery and birth weight >90th percentile. Adjusted odds ratios (aORs) were calculated according to BMI and post-OGTT glucose levels.

Results: Among the women with normal OGTT (n = 13,661), higher BMI was associated with increased risks of cesarean delivery (aOR: 2.09 [95% CI: 1.84-2.36]), preeclampsia or eclampsia (aOR: 1.99[1.37-2.89]), birth weight >90th percentile (aOR: 4.86[3.83-6.16]), and hyperbilirubinemia (aOR: 1.51[1.27-1.79]). Elevated glucose levels, even in women with a normal OGTT, increased the risks, particularly in those with a higher BMI. In the women with BMI ≥28.5 kg/m², a 1-h post-OGTT glucose level 133-155 mg/dL was associated with higher risks of cesarean delivery (aOR: 1.64[1.17-2.29]) and birth weight >90th percentile (aOR: 2.33[1.29-4.22]).

Conclusions: Higher maternal BMI and increasing maternal glucose levels significantly increased the risk of adverse perinatal outcomes, even in women with normal OGTT results.

Keywords: Body mass index; Gestational diabetes mellitus; Maternal glucose; Neonatal complications; Oral glucose tolerance test; Pregnancy outcomes.