Leng J, Li W, Wang L, et al. - In this investigation, researchers explored how maternal thyroid-stimulating hormone levels during the first trimester impacts gestational diabetes risk. There were 7,258 women who were given a thyroid-stimulating hormone screening test within 12 gestational weeks and then were given a glucose challenge test at 24–28 weeks of gestational age in Tianjin, China. The women with a glucose challenge test ≥ 7.8 mmol/l then were given a 75 g oral glucose tolerance test. Thyroid-stimulating hormone levels in the first trimester were positively related to gestational diabetes risk in pregnant Chinese women, even within the normal range; this was particularly true for prepregnancy overweight/obese women. In women with thyroid-stimulating hormone > 3.2 mIU/l, no connection was found between thyroid-stimulating hormone levels and gestational diabetes risk in univariable and multivariable analyses.