INTRODUCTION:: The Institute of Medicine (IOM) guidelines currently recommends targeting gestational weight gain (GWG) according to pre-pregnancy BMI. We compared the maternal and neonatal outcomes in women with a positive glucose challenge test (GCT) who gained weight in excess of the IOM guidelines to those who were adherent. METHODS:: A retrospective single-center cohort study including all singleton, term (>37 weeks) pregnancies with a positive GCT (>140mg/dl) delivered between 2013-2016. Patients were classified as either ‘excess’ or ‘adherent’ based on IOM GWG recommendations. Primary outcome was the rate of macrosomia (>4,000g). Secondary outcomes included rates of cesarean delivery and neonatal hypoglycemia. Baseline variables were compared using t-test or chi-square test and combined in a multivariable logistic regression model. RESULTS:: From 456 singleton-term pregnancies, 182 patients (40%) had ‘excess’ GWG. The excess cohort were younger, more likely to be African-American and have positive screening GCT with a negative diagnostic test (71% vs 58%,p<0.01). Excess cohort had greater rate of macrosomia (15% vs 5%,p<0.01), more likely to develop pre-eclampsia (10% vs 2%,p<0.01) and undergo cesarean delivery (40% vs 32%,p=0.10). The increased risk of macrosomia (OR-3.45, 95%CI 1.7-7.5) and pre-eclampsia (OR-4.8, 95%CI 1.8-15.4) remained when adjusting for age, ethnicity, and pre-pregnancy BMI. Rates of neonatal hypoglycemia were similar in both cohorts. CONCLUSION:: Women with a positive GCT, regardless of the diagnosis of gestational diabetes, gaining weight in excess of IOM guidelines have increased risk of macrosomia and pre-eclampsia. Focused counseling regarding appropriate weight gain should be considered in all women with a positive GCT.