To investigate the effect on infant blood glucose levels of an intervention consisting of early, frequent breastfeeding and two hours of immediate uninterrupted skin-to-skin contact following birth of term infants born to mothers with diet-treated gestational diabetes (GDM).Quasi-experimental study design with a historical control group (n = 132) and an intervention group (n = 401) testing a procedure to prevent neonatal hypoglycemia.Data collection on blood glucose levels, hypoglycemia incidence with a cut-off of <2.5 mmol/l, breastfeeding within the first two hours after birth, breastfeeding frequency within the first six hours, and amount of formula given to hypoglycemic infants.Mean blood glucose levels in the intervention group at two and four hours were within safe limits: 3.37 mmol/l (95% CI: [3.30, 3.44]) and 3.40 mmol/l (95% CI: [3.34, 3.46]), respectively. Infants suffering a hypoglycemic event within four hours after birth decreased from 22.7% (n = 30/132) in the control group to 10.2% (n = 41/401) in the intervention group. The mean number of breastfeeds in the intervention group (six hours) was 2.41 compared to 1.34 in the control group (seven hours), an increase of 80%. Only 41 of 401 infants in the intervention group were interrupted in immediate interaction with their mother because of hypoglycemia. We failed to obtain sufficient data on skin-to-skin contact.Maintaining skin-to-skin contact for infants of mothers with diet-treated GDM, monitoring blood glucose levels until obtaining two values >2.4 mmol/l and encouraging early frequent breastfeeding is a safe strategy to prevent hypoglycemia.