The development of obesity is more complex in women than in men because, inaddition to the usual reasons for becoming obese, the vast majority of womenbecome pregnant at some point in their life (85% by age 44yr) [1], andsubstantial weight gain is recommended for each pregnancy. Depending on awoman’s pre-pregnancy body mass index (BMI), the latest Americanguidelines [2] recommend that women be weighed during each routine prenatalcare visit and gain as little as 5kg or as much as 18kg during pregnancy(Table 19.1). Unfortunately, the weight gained during pregnancy may bedifficult to lose postpartum [3]. Women who are too heavy when they conceivehave a high risk for complications of pregnancy and difficulties with laborand delivery (reviewed in [2,4]), so it is important for women to conceiveat a normal BMI, gain weight appropriately while pregnant, and then returnto their pre-pregnancy weight postpartum before becoming pregnant again [2].

Within the American context, national public health policies and programsrelated to helping women to conceive at a healthy weight, gain weightappropriately during pregnancy, and limit weight retention postpartum willbe covered in this chapter. In addition, the specific challenges involved indeveloping guidelines for gestational weight gain (GWG) among the heaviestwomen will be considered.

The United States does not have an oi cial policy related to nutrition ingeneral or the prevention of maternal obesity more specifically. Instead ithas developed a variety of norms, standards, and targets that serve as thefoundation for action by individuals, organizations, and local, state andfederal agencies. Among other possibilities, they may be derived from thedeliberations of expert committees, whose work is ot en commissioned by thefederal government. For example, since 1970, three such committees havepublished guidelines for GWG [ 2,5,6]. This guidance not only informs thedevelopment of various federaland state-level policy instruments, asdiscussed below, but it can also be inl uential in changing the recommendedpractices or standards of care used by health care providers (e.g., theadoption of guidelines for GWG by the American Congress of Obstetricians andGynecologists) as happened recently [7].