In 2006, FNS asked the Institute of Medicine to review the WIC food packages. The IOM proposed major changes to improve nutrition and encourage breastfeeding but also expressed the concern that changes related to partial breastfeeding may have unintended consequences. The IOM recommended that FNS conduct an impact study evaluating the birth month breastfeeding changes to the WIC food packages. 

This study describes some of the choices state agencies made as they exercised the flexibility offered during the implementation and describes the resulting food packages.