Association for Public Policy Analysis & Management

A long-standing tension within the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) is promotion of breastfeeding while making available free infant formula. The WIC program purchases over half of all infant formula sold in the US and unsurprisingly, breastfeeding initiation and duration is substantially lower among WIC participants than eligible non-participants. In an effort to improve breastfeeding, the Oregon WIC Program tested whether a relatively low-cost telephone peer counseling program to support breastfeeding could increase the initiation and duration of breastfeeding. They conducted a large randomized field experiment (RFE) from 2005-2007 with over 1900 women from four WIC agencies in the state. They found significant increases in any breastfeedingamong all women and increases in exclusive breastfeeding among Spanish- but not English-speaking clients.

Increases in breastfeeding have the potential to reduce WIC outlays. The annual retail cost of the WIC food package in 2007 was $1562 for women on the full-formula package, $1668 for the partial breastfeeding package and $669 for the full breastfeeding package. Thus, peer counseling’s potential to reduce food package costs depends primarily on increases in exclusive breastfeeding.

In this study we use data from the RFE to test whether increases in breastfeeding result in lower food package redemption costs for each mother/infant pair up to 6 months postpartum. Moreover, we extend the RFE in several ways. First, we use randomization as an instrument to estimate the effect of breastfeeding on food package costs.   Second, after the RFE stopped, peer counseling continued tobe offered in the same agencies to any women who was interested.  We estimate the effect of peer counseling on breastfeeding and food package costs with the observational data and compare the experimental to the non-experimental estimates.  The contrast provides a unique opportunity to assess the potential selection bias associated with the effects of peer counseling on breastfeeding and food package costs in a real program setting in which participation is voluntary.  The estimates have important policy implications as the U.S. Surgeon General has advocated that peer counseling become a core WIC service.