RESEARCH AND PRACTICE

The New Food Package and Breastfeeding Outcomes Among Women, Infants, and Children Participants in Los Angeles County Brent A. Langellier, PhD, M. Pia Chaparro, PhD, May C. Wang, DrPH, Maria Koleilat, DrPH, and Shannon E. Whaley, PhD

Breastfeeding has long been recognized as the best source of infant nutrition,1,2 with clear benefits to both mothers and children.3 The American Academy of Pediatrics recommends that infants be exclusively breastfed for the first 6 months of life and that breastfeeding continue with appropriate complementary foods for at least 1 year or more.2 Despite improvements over the past several decades,4,5 relatively few mothers and children in the United States meet breastfeeding recommendations. Data from the 2009 National Immunization Survey suggest that just 16% of US children are exclusively breastfed for 6 months and fewer than 26% do any breastfeeding at 1 year.6 Breastfeeding outcomes vary between populations partially as a result of social and cultural norms, economics, and institutional policies and practices.7---12 For example, data from the 2007 National Immunization Survey indicate that breastfeeding initiation, duration, and exclusivity rates are comparable between Latinas and Whites, but much lower among Blacks.6 Breastfeeding rates also vary on the basis of participation in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).13 Data from the 2007 National Immunization Survey suggest that just 9.2% of WIC participants exclusively breastfeed for 6 months, compared with 19.2% of eligible nonparticipants.6 Similarly, only 17.5% of WIC participants were still breastfeeding at 1 year, compared with 30.7% of eligible nonparticipants.6 As noted by several authors, however, this gap in breastfeeding outcomes is not because participating in WIC negatively affects breastfeeding, but because those who select themselves into the WIC program are among the least likely to breastfeed.14,15 On October 1, 2009, at the recommendation of an expert panel of the Institute of Medicine, the WIC program implemented

Objectives. We assessed the effect of the new Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) food package, implemented in October 2009, on breastfeeding outcomes among a predominately Latina sample of WIC participants in Los Angeles County, California. Methods. We used data from 5020 WIC participants who were interviewed in a series of repeated cross-sectional surveys conducted in 2005, 2008, and 2011. Participants were randomly selected from Los Angeles County residents who received WIC services during those years. Results. Consistent with the WIC population in Los Angeles, participants were mostly Latina and had low levels of income and education; more than half were foreign-born. We found small but significant increases from pre- to postimplementation of the new WIC food package in prevalence of prenatal intention to breastfeed and breastfeeding initiation, but no changes in any breastfeeding at 3 and 6 months. The prevalence of exclusive breastfeeding at 3 and 6 months roughly doubled, an increase that remained large and significant after adjustment for other factors. Conclusions. The new food package can improve breastfeeding outcomes in a population at high risk for negative breastfeeding outcomes. (Am J Public Health. 2014;104:S112–S118. doi:10.2105/AJPH.2013.301330)

changes to the food package provided to mothers and children.16 A goal of this change was to provide stronger incentives to breastfeed and reduce the amount of formula given to partially breastfed infants. As a result of the new food package, mother---infant dyads who fully breastfeed now receive a food package that includes a greater quantity and larger variety of food than those who partially breastfeed or are fully formula fed.16 Specifically, infants who are fully breastfed receive double the quantity of infant fruits and vegetables when they are aged 6 to 12 months as those who are partially breastfed or fully formula fed. Fully breastfed infants are also the only group that receives infant meats from ages 6 to 12 months. Fully breastfeeding mothers receive canned fish and increased amounts of milk, cheese, eggs, and fruits and vegetables compared with partially breastfeeding and fully formula-feeding mothers.16,17 In addition, fully and partially breastfeeding mothers receive

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food for themselves for as much as 1 year, whereas fully formula-feeding mothers receive food for only 6 months. (For a summary of all WIC food packages changes, please see Cole et al.16) Despite being a clear improvement over its predecessor, questions remain about whether the new food package will substantially improve low breastfeeding rates among WIC participants.18 Many experts have pointed out that because of the high retail value of formula, the food package for fully formula-feeding dyads may still be more valuable in terms of dollars saved than the package for fully breastfeeding dyads.18,19 These concerns are at least partially supported by qualitative research among WIC mothers that has found that any free provision of formula is seen as a barrier to breastfeeding.20,21 Few studies have evaluated changes in breastfeeding rates among WIC participants since the implementation of the new food

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package. A report commissioned by the US Department of Agriculture (USDA) used several data sources to assess whether breastfeeding rates among participants at 17 local WIC agencies across the country changed after implementation of the new food package.17 Using administrative data from all mother--infant dyads at the 17 agencies, the study found that breastfeeding initiation rates remained stable after implementation of the new food package. On the basis of a survey of 1617 mothers, the same study found only marginal improvements in breastfeeding intensity among those who received the package in the first 10 weeks of life.17 Although there were few changes in breastfeeding outcomes, the study found that more mothers enrolled in the package for fully breastfeeding and fully formula-feeding dyads, and fewer enrolled in the package for partially breastfeeding dyads. Other research conducted among WIC mothers in Los Angeles, California, confirmed the finding that package enrollment shifted postimplementation, with more mothers enrolled as fully breastfeeding.22 The limited research conducted to this point has provided important early insight into some of the effects of the new food package; however, several questions still remain. One important question to consider is whether the improved package offered to fully breastfeeding mother---infant dyads affects breastfeeding outcomes beyond the first 10 weeks. For example, the new package may incentivize women who would otherwise have introduced complementary foods to extend exclusive breastfeeding by a few additional weeks or months, thereby increasing the proportion who reach the recommended 6 months.2 Another question to consider is whether the impact of the new food package varies across different WIC populations or across local WIC agencies that implement the policy differently. Although the previously mentioned USDA report found no change in breastfeeding intensity among participants nationwide, the proportion of mothers in the Western region who fed their infants exclusively or mostly breast milk during the first 10 weeks of life significantly increased.22 Although these regional findings are preliminary because of the study’s small sample size, they suggest that further research should evaluate the new food package’s effectiveness

in varying geographic, social, and policy contexts. In this study, we use survey data collected from 5020 WIC participants in Los Angeles County during 2005, 2008, and 2011 to assess changes in breastfeeding outcomes that occurred from pre- to postimplementation of the new food package. Consistent with the goals of the new food package, we hypothesized that breastfeeding initiation, duration, and exclusivity would improve among the predominately Latino WIC population in Los Angeles County.

METHODS The survey questionnaire, first administered in 2005, was based on the Los Angeles County Health Survey and adapted with extensive input from the California State WIC Division and WIC local agency staff.23 The objectives of the surveys were to assess key health indicators and health-related behaviors, as well as home and community indicators of support for families with young children. The survey questionnaires were first developed in English and then translated into Spanish, with emphasis placed on keeping language simple and consistent with the English version. The English and Spanish versions of the survey were each piloted with Englishand Spanish-speaking WIC participants to ensure clarity and consistency. Interviews were conducted by Field Research Corporation, an independent public opinion research organization, using computer-assisted telephone interviewing. Each interview averaged 20 to 25 minutes in length. Interviewers were trained in both general and specific interviewing techniques, refusal conversion, and confidentiality procedures. As many as 8 attempts were made to reach and interview eligible participants from each telephone listing dialed. All households who completed an interview were mailed a $10 gift card. The sample for each survey was randomly selected from the population of all participants receiving WIC services in Los Angeles County during January of the survey year. In brief, each survey collected data from approximately 5000 WIC participants, for a total sample size of 15 093 participants across the 3 surveys. Only persons who could complete the survey in

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English or Spanish and reported that they or a child in the household was enrolled in the WIC program were eligible for the survey. If participants reported that more than 1 child in the household was enrolled in the WIC program, data were collected regarding only the child with the most recent birthday. In general, each survey yielded an average cooperation rate of approximately 90% (ranging from 88% to 93%), indicating that when WIC participants were reached by phone, 9 out of 10 completed the survey. Response rates for the surveys, defined as the ratio of those who participated in the survey to those who were eligible, were 66.5% (n = 5015), 59.6% (n = 4998), and 54.0% (n = 5080) for 2005, 2008, and 2011, respectively. In general, less than 3% of nonresponse was because of refusal or partial interviews; rather, the vast majority of nonresponders simply could not be reached by telephone within the 8 phone call attempts.

Breastfeeding Variables Breastfeeding data were collected from all participants who reported they were the biological mother of a child enrolled in the WIC program (95% of the total sample, n = 14 298). In this study, we examined 5 breastfeeding outcomes: (1) breastfeeding initiation, (2) any breastfeeding at 3 months, (3) any breastfeeding at 6 months, (4) exclusive breastfeeding at 3 months, and (5) exclusive breastfeeding at 6 months. We coded each outcome as dichotomous, with each variable representing whether each participant achieved the outcome specified. We determined breastfeeding duration with a question asking, “How old was CHILD when you completely stopped breastfeeding him/her?” Using the most conservative definition, we defined participants as exclusively breastfeeding at 3 (or 6) months only if the mother reported all of the following: (1) no in-hospital supplementation, (2) breastfeeding duration of at least 3 (or 6) months, and (3) no supplementation before 3 (or 6) months.

Analytic Sample The focal relationship in this study was between the food package participants received and breastfeeding outcomes. We used the year of the interview to determine whether participants received the new or the old food package. In particular, participants in the 2005 and

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2008 surveys received the old food package, and participants in the 2011 survey received the new food package. Because the new food package was implemented on October 1, 2009, we restricted our analyses for the 2011 survey to the subsample of mothers whose children were born on or after that date. To ensure that age distribution was consistent across survey years, we also restricted our analyses to participants in the 2008 sample who were born after October 1, 2006, and those in the 2005 sample who were born after October 1, 2003. This date-of-birth restriction reduced our subsample to 5524 of the 15 093 total participants in all 3 surveys. We further excluded participants who were not the biological mothers of the children in question or who answered “don’t know” or “refused” for any of the questions used in our multivariate models, resulting in an analytic sample size of 5020. For each breastfeeding outcome, we further restricted our analyses to include only children as old as or older than the breastfeeding duration in question. For example, we did not include children aged younger than 3 months in the analyses of any and exclusive breastfeeding at 3 months. Thus, the final sample sizes were n = 5020 for breastfeeding initiation, n = 4407 for outcomes at 3 months, and n = 3428 for outcomes at 6 months.

Analyses We used multivariate logistic regression to assess the relationship between food package and each breastfeeding outcome. We adjusted for factors that may influence breastfeeding outcomes, including children’s age and gender; mothers’ age, race/ethnicity, education, and nativity; interview language; presence of the father in the household; and duration of time the mother had been enrolled in the WIC program for all children other than the child that was the subject of the interview.8,20,24,25 We further controlled for the mother’s prenatal intention to breastfeed, in-hospital breastfeeding behavior (none, nonexclusive breastfeeding, or exclusive breastfeeding), and whether the mother received a formula discharge pack from the hospital.10,26---30 In our multivariate models, we did not include in-hospital breastfeeding as a predictor of breastfeeding initiation or exclusive breastfeeding at 3 and 6 months because by

our definition, all mothers who breastfed in the hospital initiated breastfeeding and all mothers who exclusively breastfed for 3 or 6 months also exclusively breastfed in the hospital. We conducted all analyses using Stata version 11 (StataCorp, College Station, TX).

RESULTS Descriptive statistics for the sample of WIC participants by survey year are provided in Table 1. Participants in the 2011 survey received the new food package, and participants in the 2005 and 2008 surveys received the old food package. In all survey years, the majority of mothers were Latina, ranging from a high of

88% in 2008 to a low of 80% in 2011. Child gender, maternal age, household size, and parental cohabitation changed very little across survey years. Compared with those in the 2005 and 2008 samples, children in the 2011 sample were younger, and mothers were more likely to have at least a high school education, to be US-born, and to have been interviewed in English. Compared with mothers in the 2008 and 2011 samples, mothers in the 2005 sample had been enrolled in WIC for fewer years. Breastfeeding outcomes by survey year, unadjusted for other factors, are shown in Table 2. There was a small but statistically significant increase in prenatal intention to breastfeed,

TABLE 1—Descriptive Statistics for a Sample of WIC Children: Los Angeles County, CA; 2005, 2008, and 2011 Survey Year, % or Mean (95% CI) Characteristic Child age, mo

2005

2008

2011

9.5 (9.3, 9.8)

9.7 (9.4, 10.0)

8.6 (8.4, 8.9)

51.2

49.1

49.8

Child gender Male Female

.46 48.8

50.9

50.2

27.5 (27.2, 27.8)

27.7 (27.4, 28.1)

28.0 (27.7, 28.3)

< high school

50.3

51.3

33.9

High school graduate > high school

26.1 23.6

26.4 22.3

30.4 35.6

Latina

84.9

88.4

80.1

White

4.6

3.1

6.1

Black

6.6

5.8

9.9

Asian

2.8

1.3

1.4

Other or multiple

1.0

1.4

2.6

32.9

34.0

50.1

67.1

66.0

49.9

English

39.5

37.6

58.6

Spanish

60.6

62.5

41.4

71.7

72.0

69.2

No Household size

28.3 4.9 (4.8, 5.0)

28.0 5.0 (4.9, 5.1)

30.9 4.8 (4.7, 4.8)

Mother enrolled in WIC, y

2.6 (2.4, 2.7)

3.1 (2.9, 3.2)

3.3 (3.1, 3.5)

Maternal age, y Educational attainment

< .001

Maternal race/ethnicity

Maternal nativity US-born Foreign-born

< .001

< .001

Interview language

< .001

Father living in household Yes

P

.15

Note. CI = confidence interval; WIC = Special Supplemental Nutrition Program for Women, Infants, and Children. n = 1772 for 2005; n = 1598 for 2008; and n = 1650 for 2011. P values are based on a v2 test with the null hypothesis that the distribution of each row variable is the same across survey years. The sample size was n = 5020.

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TABLE 2—Breastfeeding Outcomes Among a Sample of WIC Participants: Los Angeles County, CA; 2005, 2008, and 2011 Survey Year, % Variable

2005

2008

2011

Pa

Prenatal intention to breastfeed

83.7

85.8

87.7

.004

Formula discharge pack at hospital

88.3

87.1

72.7

< .001

None Some (nonexclusive)

27.5 51.4

24.2 51.7

14.4 46.5

Exclusive

21.1

24.1

39.1

Ever breastfed

86.7

87.2

93.0

< .001

Breastfeeding at 3 mob

57.3

62.3

62.5

.004

Breastfeeding at 6 moc

42.7

47.9

45.3

.04

Exclusively breastfeeding at 3 mob

10.9

13.7

22.1

< .001

Exclusively breastfeeding at 6 moc

3.0

5.4

11.7

< .001

In-hospital breastfeeding

< .001

Note. WIC = Special Supplemental Nutrition Program for Women, Infants, and Children. The sample size was n = 5020. a P values are based on a v2 test with the null hypothesis that the distribution of each row variable is the same across survey years. b n = 4407 for 3-month outcomes. c n = 3428 for 6-month outcomes.

from 84% in 2005 to 86% in 2008 and 88% in 2011 (P = .004). Compared with their counterparts in the 2005 and 2008 samples, significantly fewer mothers in the 2011 sample reported receiving a formula discharge pack at the hospital (P < .001); still, more than 7 in 10 mothers in the 2011 sample received a formula pack. In-hospital breastfeeding behavior also changed, with fewer mothers in the 2011 sample reporting no in-hospital breastfeeding and more reporting exclusive breastfeeding in the hospital (P < .001). Breastfeeding initiation appears to have increased across the survey periods, from 87% in 2005 and 2008 to 93% in 2011 (P < .001). Any breastfeeding at 3 and 6 months also increased somewhat between 2005 and 2008; however, little or no change in any breastfeeding outcomes occurred between 2008 and 2011. We found large and statistically significant increases in exclusive breastfeeding between the 2005 and 2008 surveys and the 2011 survey. Just 11% of participants in the 2005 survey and 14% in the 2008 survey exclusively breastfed through 3 months, compared with 22% in the 2011 survey (P < .001). Similarly, just 3% of 2005 participants and 5% of 2008 participants exclusively breastfed through 6 months, compared with 12% in the 2011 survey (P < .001).

In Table 3, we show results from multivariate logistic regressions of breastfeeding outcomes. After adjustment for the other factors in the model, we found that participants who received the new food package had 2.2 times the odds of initiating breastfeeding (P < .001), 1.7 times the odds of exclusively breastfeeding at 3 months (P < .001), and 3.1 times the odds of exclusively breastfeeding through 6 months (P < .001). However, the new food package appears to have had little or no effect on any breastfeeding at 3 and 6 months, after adjustment for other factors. Among other factors related to breastfeeding outcomes, those with the largest influence include having a prenatal intention to breastfeed, in-hospital breastfeeding, and whether the mother received a formula gift pack on discharge from the hospital. After adjustment for other factors, mothers who intended to breastfeed had nearly 12 times the odds of initiating breastfeeding as other mothers, more than 3 times the odds of any breastfeeding at 3 and 6 months, and more than 4 times the odds of exclusively breastfeeding at 3 and 6 months (P < .001 for all outcomes). However, mothers who received a formula discharge pack from their hospital were significantly less likely than other mothers to initiate breastfeeding (P < .01), to do any breastfeeding at

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3 and 6 months (P < .001 for each outcome), and to exclusively breastfeed through 3 and 6 months (P < .001 for each outcome). Mothers who breastfed nonexclusively in the hospital had 4 and 3 times the odds of doing any breastfeeding at 3 and 6 months, respectively, as mothers who did no breastfeeding in the hospital. Moreover, mothers who exclusively breastfed in the hospital had nearly 10 times the odds of doing any breastfeeding at 3 months and more than 6 times the odds of doing any breastfeeding at 6 months as those who did no breastfeeding in the hospital. Our multivariate models also indicate that sociodemographic factors were associated with breastfeeding outcomes. Children’s age and mothers’ education, foreign nativity, and being interviewed in Spanish were all positively associated with breastfeeding outcomes. Mothers’ race/ethnicity was not associated with the odds of doing any breastfeeding at 3 or 6 months; however, breastfeeding initiation and exclusivity did vary across racial/ethnic groups. Compared with Latinas, Black mothers were less likely to initiate breastfeeding (P < .01) but more likely to be exclusively breastfeeding at 6 months (P < .01). Similarly, White mothers were more likely than Latinas to be exclusively breastfeeding at 3 (P < .01) and 6 months (P < .01). These results suggest that Latinas have high rates of breastfeeding initiation relative to other racial/ethnic groups, but also that they are more likely to supplement with foods other than breast milk.

DISCUSSION This study is among the first to evaluate changes in breastfeeding outcomes among a large population of WIC participants after implementation of the new food package. In general, a handful of previous studies have found that enrollment in the food package for fully breastfeeding mother---infant dyads increased after the new food package was implemented;17,22,31 however, studies have generally found little or no change in breastfeeding initiation or duration and intensity during the first 10 weeks of life.17,31 To our knowledge, our study provides the strongest evidence to date that actual breastfeeding behaviors improved after implementation of the new food package. By contrast with the

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TABLE 3—Multivariate Logistic Regressions of Breastfeeding Outcomes Among WIC Participants: Los Angeles, CA; 2005, 2008, and 2011 Variable New food packagea

Ever Breastfed, OR (95% CI)

Any 3 Months, OR (95% CI)

Any 6 Months, OR (95% CI)

Exclusive 3 Months, OR (95% CI)

Exclusive 6 Months, OR (95% CI)

2.16*** (1.69, 2.76)

0.95 (0.81, 1.11)

0.89 (0.75, 1.05)

1.72*** (1.43, 2.07)

3.08*** (2.27, 4.18)

Child age, mo

1.00 (0.98, 1.02)

1.04*** (1.02, 1.05)

1.02* (1.00, 1.04)

1.04*** (1.02, 1.05)

1.04* (1.00, 1.08)

Male child

1.00 (0.82, 1.22)

0.86* (0.75, 0.99)

0.91 (0.78, 1.06)

0.96 (0.80, 1.13)

1.09 (0.82, 1.44)

0.96*** (0.94, 0.97)

1.02*** (1.01, 1.04)

1.03*** (1.02, 1.05)

1.01 (0.99, 1.02)

1.01 (0.98, 1.03)

Mother age, y Mother education < high school (Ref)

1.00

1.00

1.00

1.00

1.00

High school graduate

1.26 (0.97, 1.62)

1.10 (0.92, 1.31)

1.11 (0.92, 1.35)

1.15 (0.92, 1.43)

1.25 (0.87, 1.79)

1.55** (1.16, 2.06)

1.21 (1.00, 1.48)

1.18 (0.96, 1.46)

1.34* (1.06, 1.71)

1.39 (0.94, 2.06)

> high school Mother race/ethnicity Latina (Ref)

1.00

1.00

1.00

White

0.65 (0.41, 1.03)

0.96 (0.69, 1.34)

1.23 (0.84, 1.79)

1.72** (1.16, 2.55)

1.00

2.60** (1.38, 4.90)

1.00

Black Asian

0.58** (0.41, 0.83) 0.66 (0.31, 1.37)

1.21 (0.91, 1.62) 0.70 (0.41, 1.19)

1.32 (0.95, 1.85) 0.67 (0.37, 1.21)

1.21 (0.83, 1.75) 0.78 (0.36, 1.67)

2.38** (1.31, 4.33) 0.91 (0.26, 3.22)

Other or multiple

1.28 (0.55, 2.99)

0.84 (0.49, 1.41)

0.85 (0.45, 1.61)

1.62 (0.88, 2.99)

0.71 (0.16, 3.11)

Mother foreign-born

1.82*** (1.32, 2.51)

1.41** (1.14, 1.74)

1.55*** (1.23, 1.96)

0.94 (0.72, 1.24)

1.41 (0.89, 2.24)

Interview in Spanish

1.14 (0.81, 1.60)

1.95*** (1.56, 2.45)

2.01*** (1.57, 2.58)

1.40* (1.05, 1.86)

1.85* (1.14, 3.02)

Household size

1.02 (0.96, 1.09)

0.97 (0.93, 1.01)

1.01 (0.97, 1.06)

0.97 (0.92, 1.02)

1.03 (0.95, 1.12)

Father lives in household

1.18 (0.94, 1.49)

1.19* (1.01, 1.40)

1.07 (0.90, 1.29)

1.14 (0.92, 1.40)

1.29 (0.90, 1.84)

Mother in WIC, y Intention to breastfeed Formula discharge pack at hospital

1.02 (0.99, 1.05) 11.79*** (9.61, 14.47) 0.62** (0.45, 0.86)

1.00 (0.98, 1.02)

1.00 (0.98, 1.03)

1.05*** (1.03, 1.08)

1.01 (0.97, 1.05)

3.31*** (2.67, 4.11) 0.66*** (0.54, 0.81)

3.00*** (2.30, 3.91) 0.67*** (0.54, 0.82)

4.03*** (2.71, 5.99) 0.29*** (0.24, 0.35)

4.12*** (2.01, 8.48) 0.38*** (0.28, 0.52)

In-hospital breastfeeding None (Ref)

1.00

1.00

Some (nonexclusive)

3.88*** (3.24, 4.65)

3.05*** (2.45, 3.79)

Exclusive

9.68*** (7.76, 12.07)

6.64*** (5.20, 8.49)

Note. CI = confidence interval; OR = odds ratio; WIC = Special Supplemental Nutrition Program for Women, Infants, and Children. For ever breastfeed, n = 5020; for any 3 months, n = 4407; for any 6 months, n = 3428; for exclusive 3 months, n = 4407; for exclusive 6 months, n = 3428. a Measured as year of survey participation (2005 or 2008 = old food package; 2011 = after new food package). *P < .05. **P < .01, ***P < .001.

findings of Wilde et al.,31 who found no increases in breastfeeding initiation in a national sample of WIC mothers, we found that the prevalence of breastfeeding initiation increased in our sample after the implementation of the new food package. Our multivariate analyses accounted for several potential confounders, such as changes over time in the sociodemographic characteristics of WIC participants and in-hospital factors known to have an impact on breastfeeding, including issuance of formula gift packs on discharge.32 One of the most important findings of this study is that exclusive breastfeeding at 3 and 6 months increased significantly after implementation of the new food package. This finding contrasts with the findings of an evaluation study conducted by the USDA, which found no changes in breastfeeding intensity in

their sample of 1617 WIC participants recruited from 17 WIC agencies located across the country.17 One reason for these disparate findings could be that the new food package has been implemented or received differently across the United States, resulting in heterogeneous effects by region. The findings of the USDA evaluation study provide preliminary evidence in support of this conclusion: although the authors found no improvement in breastfeeding intensity in their nationwide sample of WIC participants, they found that WIC participants in the West were more likely to be exclusively or mostly breastfeeding after the implementation of the new food package, whereas participants in the Midwest were more likely to be feeding their infants mostly formula.17 Further research will be necessary to

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confirm whether the effect of the new food package varies across regions, as well as to determine whether this variation is a result of the differences in the implementation of the new policy, the characteristics of WIC participants, or some other factor. An alternative explanation for the differences between our findings and those of the USDA evaluation study17 may be that the breastfeeding outcomes we investigated occurred over a longer period of time. The USDA study investigated breastfeeding intensity during the first 10 weeks of life; however, we examined whether mothers exclusively breastfed their infants for at least 3 and 6 months. These findings suggest that the new food package may not only encourage and support mothers to initiate exclusive

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breastfeeding but also to maintain exclusive breastfeeding over longer periods of time. Another important finding of our study is our confirmation that in-hospital policies and practices have a large and significant impact on breastfeeding outcomes, even after controlling for other factors. In particular, we found that hospitals’ provision of formula gift packs on discharge is both extremely prevalent and damaging to WIC participants’ breastfeeding outcomes. Moreover, WIC mothers who initiate breastfeeding in the hospital, particularly exclusive breastfeeding, have much better breastfeeding outcomes at 3 and 6 months. These findings, which are consistent with those of previous research,9,10,28,30,32---34 strongly suggest a need for hospitals to adopt breastfeedingfriendly policies and implement practices that support mothers to successfully breastfeed. Our study has several important limitations that must be considered when interpreting our findings. First, we lack a comparison group for our sample of WIC participants. Thus, changes in breastfeeding outcomes that we attribute to the new food package may actually have been caused by secular trends or changes that occurred concurrently with the food package implementation (e.g., improved hospital practices, varying sociodemographic characteristics of WIC participants, changes in social and cultural norms related to breastfeeding). Given research suggesting that WIC participants differ significantly from eligible nonparticipants, however, it would likely have been difficult or impossible to find a true comparison group for our sample.14 We attempted to limit the possibility of confounding by using multivariate techniques to adjust for a range of factors known to affect breastfeeding outcomes, including sociodemographic characteristics, prenatal intention to breastfeed, and hospital breastfeeding behavior and practices. A further limitation of our study is that we used data from retrospective interviews to assess breastfeeding behaviors, which introduces the possibility of recall bias. Given that all of the children in our sample were aged younger than 2 years at the time of the interview, however, and that recall bias would likely not have changed across survey years, we believe that the threat of confounding from recall bias is minimal. A further caveat of our study is that our findings may be specific to the unique WIC

population in Los Angeles County, which is predominantly Latino. As discussed, further research in other contexts is necessary to fully understand how the new food package affects WIC populations in differing geographic contexts and with varying sociodemographic profiles. We believe our study provides important preliminary evidence that the implementation of the new food package may have improved breastfeeding outcomes among WIC participants. This finding is critical because it suggests that the enhanced food package, when paired with the breastfeeding support and education that have long been a part of WIC services, can improve breastfeeding outcomes among a population known to be at high risk of negative breastfeeding outcomes. j

About the Authors At the time of the study, Brent A. Langellier and M. Pia Chaparro were with and May C. Wang is with the Department of Community Health Sciences, Fielding School of Public Health, University of California, Los Angeles. At the time of the study, Maria Koleilat was with and Shannon E. Whaley is with Public Health Foundation Enterprises, Special Supplemental Nutrition Program for Women, Infants, and Children Program, Los Angeles, CA. Correspondence should be sent to Brent A. Langellier, PhD, Division of Health Promotion Sciences, 1295 Martin Ave, Tucson, AZ 85724 (email: [email protected]. edu). Reprints can be ordered at http://www.ajph.org by clicking the “Reprints” link. This article was accepted March 5, 2013.

Contributors B. A. Langellier conceptualized the study, conducted the analysis, and wrote the article. M. P. Chaparro and M. C. Wang contributed to the conceptualization and authorship. M. Koleilat assisted with data collection and authorship. S. E. Whaley oversaw data collection, contributed to the conceptualization, and helped write the article.

Acknowledgments

3. Ip S, Chung M, Raman G, et al. Breastfeeding and maternal and infant health outcomes in developed countries. Evid Rep Technol Assess (Full Rep). 2007;(153):1---186. 4. Grummer-Strawn LM, Shealy KR. Progress in protecting, promoting, and supporting breastfeeding: 19842009. Breastfeed Med. 2009;4(suppl 1):S-31---S-39. 5. Ryan AS, Wenjun Z, Acosta A. Breastfeeding continues to increase into the new millennium. Pediatrics. 2002;110(6):1103---1109. 6. Centers for Disease Control and Prevention, Division of Nutrition Physical Activity and Obesity, National Center for Chronic Disease Prevention and Health Promotion. Breastfeeding among US children born 1999--2009: CDC National Immunization Survey. 2012. Available at: http://www.cdc.gov/breastfeeding/data/ NIS_data/index.htm. Accessed July 15, 2012. 7. Celi AC, Rich-Edwards JW, Richardson MK, Kleinman KP, Gillman MW. Immigration, race/ethnicity, and social and economic factors as predictors of breastfeeding initiation. Arch Pediatr Adolesc Med. 2005;159 (3):255---260. 8. Singh GK, Kogan MD, Dee DL. Nativity/immigrant status, race/ethnicity, and socioeconomic determinants of breastfeeding initiation and duration in the United States, 2003. Pediatrics. 2007;119(suppl 1):S38---S46. 9. Rosenberg KD, Stull JD, Adler MR, Kasehagen LJ, Crivelli-Kovach A. Impact of hospital policies on breastfeeding outcomes. Breastfeed Med. 2008;3(2):110---116. 10. DiGirolamo AM, Grummer-Strawn LM, Fein SB. Effect of maternity-care practices on breastfeeding. Pediatrics. 2008;122(suppl 2):S43---S49. 11. Roe B, Whittington LA, Fein SB, Teisl MF. Is there competition between breast-feeding and maternal employment? Demography. 1999;36(2):157---171. 12. Berger LM, Hill J, Waldfogel J. Maternity leave, early maternal employment and child health and development in the US. Econ J. 2005;115(501):F29---F47. 13. Jensen E. Participation in the Supplemental Nutrition Program for Women, Infants and Children (WIC) and breastfeeding: national, regional, and state level analyses. Matern Child Health J. 2012;16(3):624---631. 14. Colman S, Nichols-Barrer IP, Redline JE, Devaney BL, Ansell SV, Joyce T. Effects of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC): A Review of Recent Research. Alexandria, VA: US Department of Agriculture, Food and Nutrition Service, Office of Research and Analysis, Mathematica Policy Research; 2012.

Funding for this study was provided by First 5 LA. We gratefully acknowledge Lu Jiang, Eloise Jenks, Judy Gomez, Mike Whaley, and Armando Jimenez for their unique and significant contributions to this work and the WIC participants for their willingness to complete the survey.

15. Jiang M, Foster EM, Gibson-Davis CM. The effect of WIC on breastfeeding: a new look at an established relationship. Child Youth Serv Rev. 2010;32(2): 264---273.

Human Participant Protection

16. Cole N, Jacobson J, Nichols-Barrer I. WIC Food Packages Policy Options Study. Alexandria, VA: US Department of Agriculture, Food and Nutrition Service, Office of Research and Analysis; 2011.

Approval from the Independent Review Consulting institutional review board was obtained for all protocols before commencement of the study.

References 1. World Health Organization. The Optimal Duration of Exclusive Breastfeeding: Report of an Expert Consultation. Geneva, Switzerland: World Health Organization; 2001. 2. Section on Breastfeeding. Breastfeeding and the use of human milk. Pediatrics. 2012;129(3):e827---841.

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17. Wilde P, Wolf A, Fernandez M, Collins A, Robare JF. Evaluation of the Birth Month Breastfeeding Changes to the WIC Food Packages. Alexandria, VA: US Department of Agriculture, Food and Nutrition Service, Office of Research and Analysis; 2011. 18. Jensen E, Labbok M. Unintended consequences of the WIC formula rebate program on infant feeding outcomes: will the new food packages be enough? Breastfeed Med. 2011;6(3):145---149.

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RESEARCH AND PRACTICE

19. Drago R. The WIC program: an economic analysis of breastfeeding and infant formula. Breastfeed Med. 2011;6:281---286. 20. Haughton J, Gregorio D, Perez-Escamilla R. Factors associated with breastfeeding duration among Connecticut Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) participants. J Hum Lact. 2010;26(3):266---273. 21. Holmes AV, Chin NP, Kaczorowski J, Howard CR. A barrier to exclusive breastfeeding for WIC enrollees: limited use of exclusive breastfeeding food package for mothers. Breastfeed Med. 2009;4(1):25---30. 22. Whaley SE, Koleilat M, Whaley M, Gomez J, Meehan K, Saluja K. Impact of policy changes on infant feeding decisions among low-income women participating in the Special Supplemental Nutrition Program for Women, Infants, and Children. Am J Public Health. 2012;102(12):2269---2273. 23. Los Angeles County Department of Public Health. The Los Angeles County Health Survey. 2005. Available at: http://www.publichealth.lacounty.gov/ha/hasurveyintro. htm. Accessed July 30, 2010. 24. Avery M, Duckett L, Dodgson J, Savik K, Henly SJ. Factors associated with very early weaning among primiparas intending to breastfeed. Matern Child Health J. 1998;2(3):167---179. 25. Forste R, Weiss J, Lippincott E. The decision to breastfeed in the United States: does race matter? Pediatrics. 2001;108(2):291---296. 26. Chezem J, Friesen C, Boettcher J. Breastfeeding knowledge, breastfeeding confidence, and infant feeding plans: effects on actual feeding practices. J Obstet Gynecol Neonatal Nurs. 2003;32(1):40---47. 27. DiGirolamo A, Thompson N, Martorell R, Fein S, Grummer-Strawn L. Intention or experience? Predictors of continued breastfeeding. Health Educ Behav. 2005; 32(2):208---226. 28. DiGirolamo AM, Grummer-Strawn LM, Fein S. Maternity care practices: implications for breastfeeding. Birth. 2001;28(2):94---100. 29. Merewood A, Patel B, Newton KN, et al. Breastfeeding duration rates and factors affecting continued breastfeeding among infants born at an inner-city US baby-friendly hospital. J Hum Lact. 2007;23(2): 157---164. 30. Murray EK, Ricketts S, Dellaport J. Hospital practices that increase breastfeeding duration: results from a population-based study. Birth. 2007;34(3):202---211. 31. Wilde P, Wolf A, Fernandes M, Collins A. Foodpackage assignments and breastfeeding initiation before and after a change in the Special Supplemental Nutrition Program for Women, Infants, and Children. Am J Clin Nutr. 2012; 96(3):560---566. 32. Langellier B, Chaparro M, Whaley S. Social and institutional factors that affect breastfeeding duration among WIC participants in Los Angeles County, California. Matern Child Health J. 2012; 16(9):1887---1895. 33. Declercq E, Labbok MH, Sakala C, O’Hara M. Hospital practices and women’s likelihood of fulfilling their intention to exclusively breastfeed. Am J Public Health. 2009;99(5):929---935. 34. Rosenberg KD, Eastham CA, Kasehagen LJ, Sandoval AP. Marketing Infant Formula through Hospitals: The Impact of Commercial Hospital Discharge Packs on Breastfeeding. Am J Public Health. 2008;98(2):290---295.

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