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Office Prenatal Formula Advertising and Its Effect on Breast‐Feeding Patterns


Original Research

Objective: To compare the effect of formula company–produced materials about infant feeding to breast-feeding promotion materials without formula advertising on breast-feeding initiation and duration.

Methods: Five hundred forty-seven pregnant women were randomized to receive either formula company (commercial; n = 277) or specially designed (research; n = 270) educational packs about infant feeding at their first prenatal visit. Feeding method was determined at delivery. Breast-feeding duration of the 294 women who chose to breast-feed was ascertained at 2, 6, 12, and 24 weeks. Survival analyses were used to evaluate continuous outcomes, and χ2 and logistic regression analyses were used to evaluate discrete outcomes.

Results: Breast-feeding initiation (relative risk [RR] 0.93, 95% confidence interval [CI] 0.61, 1.43) and duration after 2 weeks (hazard ratio 1.19, 95% CI 0.86, 1.64) were not affected. Women in the commercial group were more likely to cease breast-feeding before hospital discharge (RR 5.80, 95% CI 1.25, 54.01) and before 2 weeks (adjusted odds ratio [OR] 1.91, 95% CI 1.02, 3.55). In subgroup analyses, women with uncertain goals for breast-feeding or goals of 12 weeks or less experienced shortened exclusive (hazard ratio 1.53, 95% CI 1.06, 2.21), full (hazard ratio 1.70, 95% CI 1.18, 2.48), and overall (hazard ratio 1.75, 95% CI 1.16, 2.64) breast-feeding duration when exposed to the commercial intervention.

Conclusion: Although breast-feeding initiation and long-term duration were not affected, exposure to formula promotion materials increased significantly breast-feeding cessation in the first 2 weeks. Additionally, among women with uncertain goals or breast-feeding goals of 12 weeks or less, exclusive, full, and overall breast-feeding duration were shortened. Educational materials about infant feeding should support unequivocally breast-feeding as optimal nutrition for infants; formula promotion products should be eliminated from prenatal settings.

In the early 1990s, infant formula manufacturers initiated the distribution of attractively packaged patient education materials that include formula advertising, samples, and business reply cards for free formula through obstetric offices. Currently, such materials are used widely in the United States to educate expectant women about infant feeding.1,2 The use of such materials violates the World Health Organization's (WHO's) international code for marketing of breast-milk substitutes, which prohibits the distribution of free samples, the promotion of formula in health care facilities, and the use of pictures idealizing artificial feeding.3

Although formula company–produced materials state clearly that breast-feeding is preferable to formula feeding, the promotion packs contain many free offers, coupons, advertisements for formula, and statements about the use of formula in a variety of situations that may concern new parents (eg, return to work). Furthermore, the distribution of commercially produced educational materials and formula samples by hospitals in the postpartum period has been shown to decrease breast-feeding duration.4–7 Studies also have demonstrated that certain high-risk groups of women including primiparas, those of low educational attainment, and those who become ill postpartum are at particular risk for shortened breast-feeding duration.6

To date, no studies have tested the hypotheses that the distribution of formula company materials, advertising, and samples through obstetrician offices affects adversely either the choice to breast-feed or breast-feeding duration. To investigate our concerns that breast-feeding might be affected adversely by these practices, we conducted a randomized clinical trial.

We hypothesized that the prenatal distribution by obstetricians of formula company infant-feeding materials compared with similar content educational materials that comply with the international code for marketing of breast-milk substitutes would decrease breast-feeding initiation; increase breast-feeding cessation in the first 2 weeks postpartum; decrease the duration of exclusive, full, and overall breast-feeding; and decrease women's personal goals for breast-feeding duration. We also hypothesized that effects of the two interventions would differ among first-time mothers, women of low educational attainment, and those who became ill postpartum. In post hoc analyses, we identified an additional at-risk group of women with personal goals for breast-feeding that were uncertain or were less than or equal to 12 weeks.

This randomized trial demonstrates that pregnant women who receive formula company patient education materials about infant feeding are at risk for shortened breast-feeding duration.

Departments of Pediatrics and Obstetrics and Gynecology, University of Rochester School of Medicine, Rochester, New York; and the Department of Community Health, Saint Louis School of Public Health, St. Louis, Missouri.

Address reprint requests to: Cynthia Howard, MD, MPH, Rochester General Hospital, Department of Pediatrics, 1425 Portland Avenue, Rochester, NY 14621; E-mail:

This study was supported by a grant from the Maternal and Child Health Bureau (MCJ-360752-01-0).

The authors thank Bruce Lanphear, MD, MPH, and Robert S. Byrd, MD, MPH, for their helpful comments during the design, implementation, and analysis of this study, and Panorama Valley-Greece Obstetrics and Gynecology, Westridge Obstetrics and Gynecology LLP, and the Faculty Practice at Rochester General Hospital for their cooperation with this study.

Received April 20, 1999. Received in revised form July 20, 1999. Accepted July 29, 1999.

© 2000 The American College of Obstetricians and Gynecologists