Blood glucose monitoring in stable small-for-gestational-age infants below 3rd percentile versus 3rd–10th percentiles on INTERGROWTH-21st charts: A quasi-randomized controlled trial

Purpose Small-for-gestational-age (SGA) infants (birth weight <10 th percentile) routinely undergo blood glucose monitoring (BGM) to detect hypoglycaemia. However, application of the INTERGROWTH-21st 10 th percentile cut-off may increase SGA classification in certain populations, potentially leading to unnecessary monitoring. This study aimed to compare the safety and effectiveness of a 3 rd centile-based BGM strategy with the conventional 10 th centile approach in stable SGA infants. Methods In this quasi-randomized controlled trial conducted at a tertiary-care centre in India (July 2024–April 2025), inborn, hemodynamically stable infants of 35 +0 to 42 +0 weeks’ gestation classified as SGA by INTERGROWTH-21st charts were enrolled within 1 hour of birth. Eligible infants were allocated to either a restricted monitoring strategy (<3 rd percentile) or a conventional monitoring strategy (3 rd –10 th percentile) using a predefined quasi-randomization method. Blood glucose was measured at predefined intervals during the first 72 h. The primary outcome was incidence of hypoglycaemia (<47 mg/dL) within 72 h. Secondary outcomes included time to full feeds, intravenous fluid requirement, sepsis, length of stay, and mortality. Results Among 324 enrolled infants (162 per group), hypoglycaemia occurred in 10.5% in the 3 rd centile group and 13% in the 10 th centile group ( p = 0.49). The absolute risk difference was 2.5% (95% CI 8.8% to 3.8%), confirming non-inferiority. No significant differences were observed in secondary outcomes. Conclusion A 3 rd centile-based BGM strategy was non-inferior to the conventional 10 th centile approach in stable SGA infants. Targeted monitoring based on severity of growth restriction may reduce unnecessary interventions without compromising short-term safety.