To date, in addition to previous studies of this cohort,21,22 only one other randomized controlled trial of metformin or insulin treatment of GDM has reported data of cognitive development of the offspring.23 Ijäs et al.21 found that motor, social, or linguistic development did not differ between 18-month-old children whose mothers were randomized to either metformin or insulin treatment of GDM. Here, INS is linked to gestational diabetes.