Many healthcare professionals and their patients are aware of the importance of proper nutrition during pregnancy, but may not be aware of specific nutritional recommendations on how to achieve a healthy pregnancy outcome. This review article aims to discuss the implications maternal nutritional status and weight gain have in both the short and long terms. Babies born to mothers with inadequate weight gain are more likely to be premature and small for gestational age (SGA). They are also predisposed to obesity and metabolic problems later in life. Women with excessive weight gain during pregnancy are at increased risk for developing type II diabetes later in life. Their offspring also have increased body fat as babies and during childhood. Pregnant women need to be informed about appropriate weight gain and how to achieve this, and should be given specific nutritional recommendations and weight-gain goals.