Maternal Pre-Pregnancy Glycemic Status and Growth Delay in Korean Children Aged 18–36 Months: A Population-Based Study

<b>Background/Objectives</b>: This study aimed at evaluating the association between maternal pre-pregnancy glycemic status and growth delay in offspring using nationwide health screening data. <b>Methods</b>: A retrospective cohort of 258,367 mother-child dyads born between 2014 and 2021 was analyzed. Maternal glycemic status was categorized as normal (<100 mg/dL), impaired fasting glucose (IFG, 100-125 mg/dL), or diabetes mellitus (DM, ≥126 mg/dL). Growth delay was defined as measurements below the 10th percentile of height, weight, and head circumference at 18-24 and 30-36 months. Visual and auditory development were assessed using caregiver questionnaires. Inverse probability of treatment weighting was applied, and weighted relative risks (RRs) were estimated. <b>Results</b>: The prevalence of growth delay was 3.5% for height, 3.8% for weight, and 4.3% for head circumference; visual and auditory problems were reported in 1.2% and 8.2% of children, respectively. Both the DM (1.2%) and IFG (9.3%) groups showed increased risks of growth delay across both age periods. Maternal hyperglycemia was also associated with offspring's visual and auditory development, with age- and period-specific differences observed. <b>Conclusions</b>: Maternal pre-pregnancy glycemic status was significantly associated with delayed growth in Korean children aged 18-36 months. These findings highlight the importance of optimizing maternal glycemic control prior to pregnancy for favorable child developmental outcomes.