Predictors of Exclusive Breastfeeding for 6 Months in a National Sample of US Children

Abstract

Purpose:

To explore predictors of breastfeeding behavior and seek to replicate prior findings using a recent nationally representative United States (US) sample, which has not been done previously.

Design:

Secondary data analysis using the National Survey of Children’s Health 2011 to 2012.

Setting:

Households in the 50 US states, the District of Columbia, and the US Virgin Islands.

Participants:

Caregivers with a child between 6 months and 6 years of age (n = 26 552).

Measures:

Caregiver-reported child breastfeeding behavior, child birth weight, child/maternal/family demographics, maternal physical and mental health, and household tobacco exposure.

Analysis:

A multinomial logistic regression explored whether child, maternal, and family characteristics predicted exclusive breastfeeding for 6 months or breastfeeding for a suboptimal duration.

Results:

Approximately 79% and 17% of the sample-initiated breastfeeding and exclusively breastfed for 6 months, respectively. Child ethnicity/race, maternal education, household tobacco exposure, family composition, and family income predicted odds of both exclusive breastfeeding for 6 months and breastfeeding for a suboptimal duration or not exclusively. Normal or high child birth weight and better maternal physical health predicted greater odds of exclusive breastfeeding for 6 months.

Conclusion:

Rates of exclusive breastfeeding for 6 months remain low in the United States. Single-parent and step-families, lower income families, non-Hispanic black children, children with exposure to tobacco, and children of mothers with lower education are at greatest risk.

Keywords

breastfeeding exclusive infant feeding infants nutrition

Purpose

Exclusive breastfeeding, defined as consumption of only breast milk (i.e., no formula or solid foods) either through breast or other means (eg, bottle), has been associated with improved infant health outcomes, including decreases in mortality,¹ overweight,² infectious diseases,^3,4 and respiratory tract infections.^5,6 Exclusive breastfeeding has also been related to earlier obtainment of motor skills milestones⁷ and improved cognitive development.⁸ A Cochrane review identified 6 months as the ideal duration for exclusive breastfeeding, noting benefits beyond exclusive breastfeeding for shorter durations (eg, 4 months).⁹ Subsequently, major health organizations, including the World Health Organization (WHO)¹⁰ and the American Academy of Pediatrics (AAP)¹¹, have recommended exclusive breastfeeding for 6 months. However, in many industrialized countries including the United States, breastfeeding duration is below desired levels. Rates of breastfeeding initiation and exclusive breastfeeding for 6 months have increased in the United States in the last 10 years (74% vs 81% and 11% vs 22%, respectively), with breastfeeding initiation rates now reaching targets of the Healthy People 2020 initiative. However, rates of exclusive breastfeeding remain suboptimal.¹²

Identifying factors associated with exclusive breastfeeding for the first 6 months allows for better identification of families at risk of not meeting this breastfeeding recommendation. While prior research has identified a range of sociodemographic, psychosocial, and individual characteristics associated with duration of breastfeeding,¹³ most of these studies have been conducted with populations outside United States or in specific population subsamples within United States rather than a population-based sample. One study did examine predictors of breastfeeding initiation and duration in a nationally representative US sample using data from the 2007 National Survey of Children’s Health (NSCH).¹⁴ In this study, maternal age, child birth weight, tobacco smoke exposure, family composition, and maternal mental health predicted exclusive breastfeeding for 6 months. However, no known study has sought to reexamine or replicate these findings using more recent data in light of continued national campaigns to promote breastfeeding in the United States (eg, Healthy People 2010 and 2020, Baby-Friendly Hospital Initiative).

The purpose of the current study was to determine whether risk factors identified in an earlier population-based study remain predictors for breastfeeding behavior in a current nationally representative sample of US children. Predictors of exclusive breastfeeding for 6 months and predictors of breastfeeding but for a suboptimal duration of exclusivity were explored. Based on prior research,^13,14 it was hypothesized that demographic (eg, race/ethnicity), family (eg, composition/structure, income), and maternal (eg, age, education) characteristics would predict breastfeeding behavior. Additionally, the current study builds on past research using a different analyses methodology than the previous study with a prior NSCH data set. Specifically, Jones and colleagues¹⁴ explored predictors of breastfeeding initiation among the entire sample and then predictors of exclusive breastfeeding among the subset of breastfed children. However, the current study instead explored predictors of children falling into 3 categories: never breastfed, breastfed for suboptimal duration or suboptimal exclusivity, and met breastfeeding recommendations (ie, breastfed exclusively for 6 months).

Methods

Design

We conducted a secondary analysis of the NSCH 2011-2012, a telephone-based survey in the United States, examining children’s health and development.¹⁵ Randomly sampled telephone number dialing was used to approach potential participants, and if a child aged 0 to 17 was living in a contacted home, the family was asked to participate. Telephone and cellular telephone interviews were conducted to complete the NSCH survey questions in 2011 through 2012.¹⁵ One child at each household was randomly selected to be the subject of questions. This secondary analysis was approved by the authors’ university-based institutional review board. Permission for the investigators to analyze data was provided by the Data Resource Center for Child and Adolescent Health.

Sample

Participants were 26 552 caregivers of children between the ages of 6 months and 6 years. This is the subset of NSCH participants who completed questions regarding breastfeeding behavior. Analyses were also limited to data representing children with mothers aged 21 to 58 years, given our interest in examining the impact of maternal age on breastfeeding outcomes and the relatively small number (n = 726) of mothers with ages outside this range. Surveys were completed by primary caregivers of children living in all 50 US states, the District of Columbia, and the US Virgin Islands. Participants were primarily mothers (either biological, step, foster, or adoptive; n = 18 281) or fathers (either biological, step, foster, or adoptive; n = 6317) of the target child. In the NSCH 2011-2012, caregivers of children between the ages of birth and 6 years completed questions regarding breastfeeding practices. For this secondary analysis, we included caregivers of children between the ages of 6 months and 6 years who had complete responses to all breastfeeding-related questions; children under 6 months were excluded since they did not yet have the opportunity to achieve the recommendation for exclusive breastfeeding.

Measures

All measures were assessed via caregiver report survey questions.

Child characteristics

These included sex (1 = male, 2 = female), ethnicity and race, and birth weight. Ethnicity and race were analyzed as a nominal variable consisting of the following categories: non-Hispanic white (reference class), non-Hispanic black, Hispanic, and multiracial/other. Birth weight was analyzed as an ordinal variable defined as the following categories: < 1500 g (extremely low), 1500 to 2499 g (low), ≥ 2500 g (normal and high).

Maternal characteristics

All participating caregivers reported on maternal characteristics, specifically current age, education, and physical and mental health. Age was reported rounding down to the last complete integer year. Education was an ordinal variable with the following categories: less than high school degree, high school degree, and more than high school degree. Physical health and mental health were reported separately using a 5-point Likert-type scale ranging from excellent (1 point) to poor (5 points), which was reverse coded (higher scores indicated better physical and mental health) for the current analysis.

Family characteristics

Several questions assessed the composition of the family in the child’s home. Family composition was analyzed as a nominal variable coded in the NSCH data set into one of the following categories: (1) 2-parent biological or adoptive (reference class); (2) 2-parent step family; (3) single mother with no father present; and (4) other family type. Caregivers also reported the total combined family income before taxes during the last calendar year for all members of the family. If the caregiver was uncertain of the family’s income, they were asked to identify a range for their family’s income (eg, was family income above or below $20 000). Income was classified as a percentage of the federal poverty level (FPL) and defined as an ordinal variable with the following categories: 0% to 99% FPL, 100% to 199% FPL, 200% to 399% FPL, and 400% FPL or greater. To assess household tobacco exposure, caregivers were asked “Does anyone in your household use cigarettes, cigars, or pipe tobacco?” and respondents who indicated “yes” were asked “Does anyone smoke inside the child’s home?” Tobacco smoke exposure was analyzed as an ordinal variable with the following categories: (1) no one uses tobacco, (2) someone uses tobacco not inside the home, or (3) someone uses tobacco and smokes inside the home.

Breastfeeding behaviors

Breastfeeding, formula feeding, and introduction of solid food behaviors were assessed through a series of questions including whether the child was ever breastfed or fed breast milk; age at which a breastfed child was introduced formula; and age of child when first fed anything other than breast milk or formula. For this secondary analysis, breastfeeding behavior, the dependent variable, was coded categorically (nominally) as 0 = child never breastfed, 1 = child breastfed but did not reach 6 months of exclusive breastfeeding, or 2 = children breastfed exclusively for 6 months (ie, met the breastfeeding recommendation). Children who never breastfed were used as the reference group in all the analyses.

Analysis

A multinomial logistic regression model was used to examine predictors of breastfeeding behavior. Analyses were conducted in Mplus (version 7.8)¹⁶ using a weighting procedure utilized by the NSCH to both account for the complex sampling design and compensate for disproportionate sampling of subpopulations. Four data set variables (“STATE”, “SAMPLE”, “IDNUMBER”, and “NSCHWT”) were used as population stratification, cluster, and weight variables, respectively, to obtain accurate parameter estimates and standard errors. The multinomial logistic regression model examined predictors of (1) children reaching 6 months of exclusive breastfeeding and (2) children being breastfed for a duration less than 6 months or not exclusively, compared to children who never breastfed (reference class). The following predictors were all entered simultaneously into each model to predict breastfeeding behavior: child birth weight, child sex, child ethnicity/race, family composition, income, maternal education, maternal age, maternal physical health, maternal mental health, and household tobacco exposure. Therefore, the relationship between each individual predictor and breastfeeding outcome was assessed while controlling for other predictors. Missing data were minimal (0.1%-8.3%) and was handled via the default maximum likelihood estimation algorithm using techniques to appropriately handle the predictor variable (ie, missing on X) missing data.¹⁷

Results

Participant Description

In this secondary analysis, 26 552 caregivers were included whose children were between the ages of 6 months and 6 years. Analyses were also limited to data regarding children with mothers between 21 and 58 years of age. Children were 13 520 males (50.9%) and 13 012 females (49.0%). Children were predominantly non-Hispanic white (61.5%, n = 16 334), and born at a normal or high birth weight (88.8%, n = 23 567). Most children lived in 2-parent biological or adoptive homes (76.4%, n = 20 282) and had mothers who had at least some post-high school education (70.0%, n = 18 575). Table 1 provides complete participant demographics.

Table 1.

Participant Demographics.

	n (%)^a
Child age
6 months-1 year	2579 (9.7%)
1	4655 (17.5%)
2	3896 (14.7%)
3	5181 (19.5%)
4	5160 (19.4%)
5	5081 (19.1%)
Child sex
Male	13 520 (50.9%)
Female	13 012 (49.0%)
Data missing	20 (0.1%)
Child race
White, non-Hispanic	16 334 (61.5%)
Black, non-Hispanic	2331 (8.8%)
Hispanic	3987 (15.0%)
Multiracial/other non-Hispanic	3276 (12.3%)
Data missing	624 (2.4%)
Family income
0%-99% FPL	4879 (18.4%)
100%-199% FPL	5050 (19.0%)
200%-399% FPL	7736 (29.1%)
400% FPL or greater	8887 (33.5%)
Maternal education
Less than high school degree	1862 (7.0%)
High school degree	4308 (16.2%)
More than high school degree	18 575 (70.0%)
Data missing	1807 (6.8%)
Family composition
Two-parent biological or adoptive	20 282 (76.4%)
Two-parent step-family	617 (2.3%)
Single mother	3983 (15.0%)
Other family type	1355 (5.1%)
Data missing	315 (1.2%)
Child birth weight
< 1500 g (extremely low)	417 (1.6%)
1500-2499 g (low)	2019 (7.6%)
>2500 g (normal and high)	23,567 (88.8%)
Data missing	549 (2.1%)
Gestational age
Less than 37 weeks	3141 (11.8%)
37 weeks or greater	23 333 (87.9%)
Data missing	78 (0.3%)
Child ever breastfed
Yes	20 848 (78.5%)
No	5704 (21.9%)
Child EBF for 6 months
Yes	4396 (16.6%)
No	22 156 (83.4%)

Abbreviations: FPL, federal poverty level; EBF, exclusively breastfed.

^a All sample sizes and percentages provided are unweighted.

Rates and Predictors of Exclusive Breastfeeding for 6 Months Compared to Never Breastfeeding

Approximately 78.5% of the sample (n = 20 848) was ever breastfed, and approximately 16.6% of the sample (n = 4396) met the recommendation of exclusive breastfeeding for the first 6 months of life.

Child characteristics

Child birth weight and ethnicity/race were significant predictors of exclusively breastfed (EBF) for the first 6 months. Infants born at normal/high birth weight were more likely to meet the exclusive breastfeeding recommendation than their low birth weight counterparts (odds ratio [OR] = 1.39 95% confidence interval [CI]: 1.08-1.79). Hispanic children were more likely to meet the exclusive breastfeeding recommendation (OR = 1.65 95% CI: 1.23-2.22) than non-Hispanic white children, but non-Hispanic black children (OR = .57 95% CI: 0.41-0.78) were less likely to meet the recommendation than their non-Hispanic white counterparts even when controlling for other sociodemographic factors. Child sex was not a significant predictor of EBF for the first 6 months. See Table 2 for complete model results.

Table 2.

Regression Coefficients for Predictors of Children Who Were Breastfed Exclusively for 6 Months Compared to Children Who Were Never Breastfed.

Variable	B	Standard Error	Wald Z	P	OR	CI
Child characteristics
Birth weight	0.33	.13	2.56	.01	1.39	1.08-1.79
Ethnicity/race
Non-Hispanic white	Ref
Hispanic	0.50	.15	3.30	.001	1.65	1.23-2.22
Non-Hispanic black	−0.57	.16	−3.50	<.001	.57	0.41-0.78
Multiracial/other race	<0.01	.14	−.02	.99
Sex	0.08	.09	.86	.39
Maternal characteristics
Physical health	0.15	.06	2.41	.02	1.17	1.03-1.32
Education	0.38	.09	4.03	< .001	1.46	1.21-1.75
Age	−0.01	.01	−.93	.35
Mental health	−0.01	.07	−.16	.87
Family characteristics
Tobacco exposure	−0.84	.10	−8.10	< .001	.43	0.35-0.53
Family composition
Two-parent biological or adoptive	Ref
Single-parent home	−0.91	.14	−6.59	< .001	.40	0.31-0.53
Two-parent step-families	−0.51	.25	−2.02	.04	.60	0.37-0.98
Other composition	−1.44	.26	−5.63	< .001	.24	0.15-0.39
Income	0.19	.06	3.33	.001	1.21	1.08-1.36

Abbreviations: CI, confidence interval; OR, odds ratio. Bold face indicates statistically significant findings.

Maternal characteristics

Maternal physical health and education were significant predictors of EBF for the first 6 months. Children of mothers with better physical health (OR = 1.17 95% CI: 1.03-1.32) and mothers with higher levels of education (OR = 1.46 95% CI: 1.21-1.75) were more likely to be EBF for the first 6 months. Maternal age and mental health did not predict exclusive breastfeeding for the first 6 months.

Family characteristics

Regarding family environment, children with greater household tobacco exposure were less likely to reach the exclusive breastfeeding recommendation than children with less tobacco smoke exposure (OR = 0.43 95% CI: 0.35-0.53). Family composition was also related to exclusive breastfeeding for the first 6 months: children living in single-parent homes (OR = 0.40 95% CI: 0.31-0.53), 2-parent step-families (OR = 0.60 95% CI: 0.37-0.98), or families with “other” compositions (OR = 0.24 95% CI: 0.15-0.39) were less likely to meet the exclusive breastfeeding recommendation than children in married biological or adoptive 2-parent homes. Higher family income was also related to greater exclusive breastfeeding (OR = 1.21 95% CI: 1.08-1.36).

Predictors of Breastfeeding for a Suboptimal Duration or Not Exclusively Compared to Never Breastfeeding

Child characteristics

Ethnicity/race was a significant predictor of breastfeeding that was less than 6 months in duration or not exclusive. Hispanic children were more likely than non-Hispanic white children to have some breastfeeding but not meet the exclusive breastfeeding recommendation (OR = 1.92 95% CI: 1.50-2.44), while non-Hispanic black children were less likely than their non-Hispanic white counterparts to have initiated breastfeeding but not met the recommendation (OR = .65 95% CI: 0.53-0.80). Child sex and birth weight were not related to ever breastfeeding but not reaching 6 months of exclusive breastfeeding. See Table 3 for complete model results.

Table 3.

Regression Coefficients for Predictors of Children Who Were Breastfed for Less Than 6 Months or Not Exclusively Compared to Children Who Were Never Breastfed.

Variable	B	Standard Error	Wald Z	P	OR	CI
Child characteristics
Birth weight	−0.03	.08	−.40	.69
Ethnicity/race
Non-Hispanic white	Ref
Hispanic	0.65	.12	5.23	< .001	1.92	1.50-2.44
Non-Hispanic black	−0.43	.11	−4.07	<.001	.65	0.53-0.80
Multiracial/other race	−0.10	.11	−.98	.33
Sex	−0.02	.07	−.31	.76
Maternal characteristics
Physical health	0.04	.04	.97	.34
Education	0.45	.06	6.96	< .001	1.56	1.38-1.77
Age	−0.01	.01	−1.81	.07
Mental health	−0.09	.05	−2.00	.05	.91	0.83-1.00
Family characteristics
Tobacco exposure	−0.49	.07	−7.37	< .001	.61	0.54-0.70
Family composition
Two-parent biological or adoptive	Ref
Single-parent home	−0.34	.10	−3.61	< .001	.71	0.59-0.86
Two-parent step-families	−0.38	.17	−2.20	.03	.68	0.49-0.96
Other composition	−1.51	.19	−8.18	< .001	.22	0.15-0.32
Income	0.21	.04	5.25	< .001	1.24	1.14-1.34

Abbreviations: CI, confidence interval; OR, odds ratio. Bold face indicates statistically significant findings.

Maternal characteristics

Children with mothers having greater education were more likely to have breastfed for a duration of exclusivity less than 6 months (OR = 1.56 95% CI: 1.38-1.77). A negative relationship was found between maternal mental health (OR = .91 95% CI: 0.83-1.00) and initiating breastfeeding but not meeting the recommendation. No relationships were found for maternal physical health or age.

Family characteristics

Children with greater household tobacco exposure were less likely to breastfeed for less than 6 months of exclusivity (OR = .61 95% CI: 0.54-0.70). Household composition was also related to children breastfeeding for less than 6 months exclusively. Children living in single parent homes (OR = .71 95% CI: 0.59-0.86), 2-parent step-families (OR = .68 95% CI: 0.49-0.96), and other family compositions (OR = .22 95% CI: 0.15-0.32) were less likely to breastfeed than children living in 2-parent married biological or adoptive families. Children in families with higher financial incomes (OR = 1.24 95% CI: 1.14-1.34) were also more likely to ever breastfeed but not meet recommendations.

Discussion

The current study evaluated child, maternal, and family predictors of breastfeeding behavior among children in the United States using a large national data set. We found that although breastfeeding was initiated with 79% of infants, only 17% were EBF for 6 months as recommended by the AAP and WHO. Several sociodemographic characteristics were associated with both exclusive breastfeeding for 6 months (defined as solely breastfeeding for 6 months without formula or solid food introduction) and initiation of breastfeeding but not reaching exclusive breastfeeding for 6 months. These factors included race/ethnicity, maternal education, household tobacco exposure, family composition, and family income. Child normal or high birth weight and better maternal physical health were also associated with greater odds of exclusive breastfeeding for 6 months (ie, meeting the breastfeeding recommendation).

Our study builds on previous published work examining predictors of exclusive breastfeeding for 6 months among US children using a nationally representative sample from the NSCH 2007, the precursor to the national data set used in the current study.¹⁴ Our analysis examined NSCH data collected in 2011 to 2012, thereby updating the results reported by Jones and colleagues.¹⁴ Rates of breastfeeding initiation in our analysis (79% compared to 75%) and rates of exclusive breastfeeding for 6 months (17% compared to 13%) were similar to those reported in Jones and colleagues with a noted slight increase. Our study did demonstrate slightly higher rates of initiation (79% compared to 74%) but lower rates of exclusive breastfeeding for 6 months (17% compared to 22%) than data recently published by the Centers for Disease Control and Prevention.¹² These results support that while breastfeeding initiation rates are high, breastfeeding duration still lags behind recommendations. Significant intervention efforts have targeted increasing breastfeeding initiation rates (eg, Healthy People 2010 and 2020, Baby-Friendly Hospital Initiative), but additional intervention is clearly needed to help families reach the recommendation of exclusive breastfeeding for 6 months.

Similar to Jones and colleagues,¹⁴ our study found that there were several factors associated with exclusive breastfeeding for 6 months. Specifically, we replicated Jones and colleagues’ findings that child birth weight, household tobacco exposure, and family composition are related to exclusive breastfeeding for 6 months. However, unlike Jones and colleagues, we also found child ethnicity, maternal education, and family income to be related to exclusive breastfeeding, and we were unable to replicate their prior findings that maternal age and mental health are related to exclusive breastfeeding. This complex pattern of predictors of exclusive breastfeeding suggests that the landscape of breastfeeding barriers may be ever changing and suggests breastfeeding rates and predictors should be frequently reassessed at the national level due to the dynamic nature of these behaviors. However, it is also important to note that methodological differences between our study, and Jones and colleagues¹⁴ could also contribute to variations in our scientific findings. Specifically, Jones and colleagues examined predictors of ever breastfeeding by comparing all children who were ever breastfed to all children who were never breastfed and then examined predictors of exclusive breastfeeding for 6 months by comparing children who breastfed exclusively for 6 months to only children who initiated breastfeeding but did not reach the recommendation of exclusive breastfeeding. Conversely, our study compared children who were breastfed exclusively for 6 months to children who never breastfed and then children who breastfed but for suboptimal duration or not exclusively to children who never breastfed. However, both studies do suggest that we need to continue to target specific populations in promoting breastfeeding initiation and exclusive breastfeeding for the recommended duration.

As noted, children born at low birth weight have consistently been found to be at greater risk of not reaching the breastfeeding recommendation for duration of exclusivity. We found that normal and high birth weight children were more likely to be EBF for 6 months compared to low and very low birth weight children. This is consistent with previous literature which has shown that infants who have a below normal birth weight are less likely to be EBF to 6 months.^14,18,19 This may be due to low-birth weight infants necessitating supplementation with calorically dense formulas, including during neonatal intensive care unit (NICU) stays or deficits in oral motor skills that make breastfeeding less optimal to initiate.²⁰ Recent efforts have been made in NICU settings to promote breastfeeding or supplementation with expressed breast milk, and initial evidence suggests effectiveness for many of these programs.²¹ Future research will be needed to examine whether such efforts increase the rates of exclusive breastfeeding in this population.

Several sociodemographic factors were found to be related to exclusive breastfeeding. Specifically, we found that non-Hispanic black infants are at increased risk of both not reaching the breastfeeding recommendation for duration of exclusivity and of not initiating breastfeeding at suboptimal levels. Additionally, children of mothers with lower education and from families with lower incomes were also found to have lower odds of breastfeeding, either to recommended levels or to shorter periods of exclusivity. This highlights the need to target these populations in breastfeeding promotion efforts and may also be reflective of the fact that low socioeconomic status (SES) populations experience a number of barriers to receiving health care in general and have poor access to the medical care system.^22,23

When examining family characteristics, our results show that children living with either 2 biological or 2 adoptive parents are more likely to be EBF for 6 months than children in single-parent homes, families with a step-parent, or other family compositions. It may be the case that additional stressors or instability in single-parent homes, homes with a step-parent, or other family compositions pose a barrier to breastfeeding. Past research has demonstrated single motherhood as a risk factor for not initiating breastfeeding and of early cessation of breastfeeding.^24,25 Interestingly, our study found single motherhood to be a risk factor even when controlling for other demographic factors such as family income, maternal education, and maternal age. Social support, including from spouses or significant others, has been related to initiation and duration of breastfeeding,²⁶ while promotion of paternal breastfeeding knowledge also has been associated with breastfeeding initiation.²⁷ This suggests the importance of involving fathers or significant others in breastfeeding interventions; medical providers should provide breastfeeding education to partners and significant others of their pregnant patients on how they can be supportive of breastfeeding in order to promote breastfeeding among their patients.

Our study also demonstrated that children with greater household tobacco exposure are less likely to be EBF for 6 months, even when controlling for other factors such as maternal education, maternal age, and family income. Previous literature has supported this finding showing consistently that tobacco exposure is inversely associated with exclusive breastfeeding.^18,19,24,28 Taken collectively, this emphasizes the need to counsel mothers prenatally regarding smoking cessation. Exposure to tobacco smoke during infancy has also been related to a number of other significant health problems for children (eg, sudden infant death syndrome and increased respiratory tract infections, asthma),²⁹ which suggests that the negative impact of tobacco smoke exposure on breastfeeding is part of a larger profile of negative consequences of maternal and familial smoking.

One study limitation was the use of caregiver report of breastfeeding practices with caregivers of older children recalling these behaviors several years after their occurrence. Research does support the validity of parental recall of breastfeeding duration for years after cessation,³⁰ but this validity has largely been demonstrated for only maternal report, and some reporters in the current study were fathers or other caregivers. Additionally, most variables were assessed using single caregiver-reported items, which may not fully assess for the complexity of some study variables (eg, maternal mental or physical health). Other cultural and maternal factors (eg, beliefs and knowledge about breastfeeding) previously associated with breastfeeding intent, initiation, and duration^31,32 also were not assessed in the current study. Further, our study defined exclusive breastfeeding as consuming solely breast milk regardless of whether this was directly from the breast or through expressed milk. It is possible that both predictors of consumption of breast milk and benefits of breast milk may vary based on whether this is directly from the breast compared to expressed breast milk. Our study also did not assess maternal perceptions of barriers to extended exclusive breastfeeding. Further, it should be kept in mind that the recommendation of 6 months of exclusive breastfeeding is a minimum recommendation, and additional research is needed regarding whether extended durations of breastfeeding are associated with any incremental benefits. Finally, the NSCH collapses 2-parent biological and 2-parent adoptive families into one category, which is a limitation for our study given breastfeeding barriers and behaviors may differ between adoptive and biological families. However, given modern advances in donation and sharing of breast milk, the increased recent popularity of milk banks and donor milk, and the potential health benefits of use of donor milk,^33,34 it is still possible for adoptive families to breastfeed their child exclusively for 6 months.

Clinical and Policy Implications

Rates of exclusive breastfeeding of infants through 6 months of age continue to remain low in the United States, despite recent increased efforts to promote initiation of breastfeeding. Clear steps for promoting initiation of breastfeeding in neonatal hospital environments and birthing centers have been outlined by the WHO and encouraged through the Baby-Friendly Hospital Initiative since 1991.³⁵ However, only more recently have similar guidelines been provided regarding how to establish a breastfeeding-friendly pediatrician office, which includes support for continued breastfeeding.^36,37 Given frequent well-check visits occur during infancy, pediatrician offices provide 1 avenue for providing support and education regarding maintenance of breastfeeding to 6 months. In fact, the Ten Steps to Support Parents’ Choice to Breastfeed their Baby outlined by the AAP Section on Breastfeeding include discussing breastfeeding at each well-check visit and providing anticipatory guidance to support continuation of breastfeeding.³⁸ Low rates of exclusive breastfeeding in the sample as a whole supports the AAP guideline that breastfeeding should be discussed at each well-check visit and highlights how all families need continued support regarding continuation of breastfeeding. Our findings support that pediatricians should provide universal education and anticipatory guidance regarding continuation of breastfeeding. Further in addition to these universal efforts, additional problem-solving and assessment of barriers is needed for at-risk populations such as single parent or step-families, non-Hispanic black infants, families where there is tobacco exposure, and families of lower socioeconomic status (eg, mothers with lower education, families with lower income). However, despite suggestions by the AAP Section on Breastfeeding, many health-care providers report lacking sufficient knowledge regarding breastfeeding,³⁹ and nearly one-third of pediatricians have reported not believing that the benefits of breastfeeding outweigh the potential difficulties or inconvenience.⁴⁰ Future research should explore rates of implementation of recommendations for breastfeeding–friendly pediatrician offices and the Ten Steps to Support Parents’ Choice to Breastfeed their Baby, including barriers to implementation and physician and practice factors related to implementations rates.

Given rates of breastfeeding through 6 months remain low across families, universal public health initiatives and policy changes represent other possible avenues for supporting population-wide change to breastfeeding behavior. National campaigns and public health interventions supporting continued breastfeeding following initiation are needed, given barriers to reaching 6 months of exclusive breastfeeding remain for all populations. Changes to national legislation and maternal work policies represent one avenue for overcoming some universal barriers to breastfeeding in the United States. In fact, the Lancet Breastfeeding Series Group has suggested that supports for breastfeeding be implemented at many levels, including changes to social norms and values, legal and policy directives, employment conditions, health care, and the infant formula industry.⁴¹ Maternal employment outside the home is one factor that has consistently been related to poor breastfeeding duration. In a national sample of US mothers, only 26.1% of mothers employed full time were still breastfeeding when the infant was 6 months old, compared to 35.0% of nonworking mothers or 36.6% of mothers working part time.⁴² Although the Affordable Care Act (ACA) makes great strides in improving workplace policy regarding breaks for breastfeeding, the ACA does not apply universally across all employers⁴³ and does not mandate paid leave time for new mothers. Establishment of federal or state laws that reduce barriers to breastfeeding among working mothers could be beneficial.

So What? Implications for Health Promotion Practitioners and Researchers?

What is already known on this topic?

In 2007, maternal, child, and family factors were found to be associated with initiation of breastfeeding in the United States and to differentiate those who meet the recommendation of exclusive breastfeeding for 6 months from those who do not.

What does this article add?

Rates of exclusive breastfeeding for 6 months remain low, despite attention to this public health issue. Rates are suboptimal in the overall sample, but certain populations are at greatest risk (eg, children with low birth weight, children of low SES, non-Hispanic black children, and children with household tobacco exposure).

What are the implications for health promotion practice or research?

Population-wide efforts to promote and support continued breastfeeding are clearly needed in addition to added support for at-risk populations. Public health initiatives, policy changes, and support for continued breastfeeding during child well-check visits may represent possible avenues for promoting greater adherence to exclusive breastfeeding for 6 months at a population level.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

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