INTRODUCTION:: To assess whether the patterns of gestational weight gain (GWG) in a rural population changed after the release of the 2009 Institute of Medicine (IOM) guidance on GWG modified by maternal pre-pregnancy body mass index (BMI). METHODS:: We examined GWG in 18,217 term singleton births between 2006 and 2015 in which maternal pre-pregnancy BMI and GWG could be calculated from electronic medical records at Geisinger in PA. RESULTS:: The proportion of births with recorded maternal pre-pregnancy BMI and data to calculate GWG increased after 2010, suggesting greater effort in tracking maternal weight. However, the pattern of GWG did not change between 2006 and 2015, with the proportion of women who gained outside of recommendations remaining constant. Only 26% of women in this population gained within recommendations. More than 50% of overweight and obese women gained above IOM recommendations in all years. Underweight women were the most likely to gain below recommendations (33%). GWG above recommendations was associated with higher birthweight, low Apgars and a greater increase in maternal blood pressure throughout pregnancy. Underweight women who gained below recommendations had the highest proportion of low birth weight babies (10.4%). CONCLUSION:: Despite the publication of IOM recommendations in 2009 and an apparent increase in tracking maternal weight after 2010, GWG in this population did not change between 2006 and 2015. A majority of overweight and obese women gained above recommendations and one third of underweight women gained below recommendations. GWG outside of IOM’s recommendations was associated with poorer outcomes.