 study looked at associations of gestational weight gain, GWG, outside 2009 IOM guidelines with maternal and infant outcomes across the USA, Western Europe and East Asia. Preterm birth, macrosomia, caesarean section and gestational diabetes were primary outcomes. Women in the USA and Western Europe have higher rates of GWG above guidelines than women in East Asia when using regional BMI categories. This article was authored by Rebecca F. Goldstein, Sally K. Able, Sanjeev Arunasenia and others.