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Time Off Work After Childbirth and Breastfeeding Supportive Workplaces: Associations with Near-Exclusive Breastfeeding Trajectory Membership
Women's Health Issues xxx-xx (2019) 1–7
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Original article
Time Off Work After Childbirth and Breastfeeding Supportive Workplaces: Associations with Near-Exclusive Breastfeeding Trajectory Membership Mackenzie D.M. Whipps, BSc, CLC a, Julia Honoroff, BA b,* a
New York University Steinhardt School of Culture, Education, and Human Development, New York, New York Institute of Human Development and Social Change, New York University Steinhardt School of Culture, Education, and Human Development, New York, New York b
Article history: Received 8 January 2019; Received in revised form 19 August 2019; Accepted 22 August 2019
a b s t r a c t Objective: We aimed to determine whether the association between time off work and a near-exclusive breastfeeding trajectory is moderated by perceived employer support for breastfeeding. Methods: We conducted a secondary analysis of working mothers (n ¼ 1,468) from the Infant Feeding Practices Study II, a longitudinal observational (2005–2007) study of U.S. infant feeding behaviors. Previous studies have found four latent infant feeding subgroups in the Infant Feeding Practices Study II sample, each following a distinct breastfeeding intensity trajectory. Multivariate least-squares regression was conducted to estimate whether time off work after delivery predicted increased membership in the subgroup characterized by near-exclusive breastfeeding, and whether this association was moderated by perceived employer support for workplace breastfeeding. Results: Both time off work and perception of more breastfeeding support were independently, positively related to probability of membership in the near-exclusive breastfeeding trajectory (b ¼ 0.16, p ¼ .019, and b ¼ 0.14, p ¼ .004, respectively). The interaction of these two factors suggests an attenuation effect. The addition of paid leave to the model did not change the estimates. Conclusion: The positive relationship between time off and trajectory membership was significant only for mothers who perceived their workplaces to be unsupportive of breastfeeding. Ó 2019 Jacobs Institute of Women's Health. Published by Elsevier Inc.
It is well-established that absent or truncated breastfeeding adversely effects maternal health and well-being, increasing the risks of some reproductive cancers and other noncommunicable diseases like diabetes (Chowdhury et al., 2015). Although various national health organizations promote and recommend exclusive breastfeeding for 6 months and continued breastfeeding for at least 1 year (American Academy of Pediatrics, 2012), a large proportion of U.S. mothers do not meet these benchmarks
Funding Statement: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors have no conflicts of interest to declare. * Correspondence to: Julia Honoroff, BA, New York University Steinhardt School of Culture, Institute of Human Development and Social Change, 627 Broadway, Room 711, New York, NY 10012. Phone: 201-655-1963. E-mail address: [email protected] (J. Honoroff).
(Bartick et al., 2017; Centers for Disease Control and Prevention, 2016). Decades of research has sought to understand the predictors of breastfeeding in the United States in an effort to support breastfeeding success. Exposure to racism, especially as an African American or Latina mother and especially in the U.S. South, has been shown to predict shorter breastfeeding durations and/ or lower breastfeeding exclusivity (Griswold et al., 2018; Ma & Magnus, 2012). Poverty and enrollment in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) have a complex relationship to breastfeeding success as well; formal WIC policies seem to promote exclusive breastfeeding, but common practices by WIC counselors and implementation of those policies may actually encourage infant formula use (Baumgartel & Spatz, 2013). Younger maternal age and lower maternal education, as well as certain infant health markersdsuch as late preterm or early term birth as compared
1049-3867/$ - see front matter Ó 2019 Jacobs Institute of Women's Health. Published by Elsevier Inc. https://doi.org/10.1016/j.whi.2019.08.006
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to full term birthdare also risk factors for early termination of breastfeeding (Radtke, 2011; Whipps, 2017). The context of a mother’s return to employment appears to one primary factor in long-term breastfeeding success for U.S. mothers. In the United States, approximately one-half of the women in the workforce are of childbearing age (between ages 16 and 44), and approximately 60% of mothers with children younger than 3 years old are employed full time (U.S. Department of Labor: Women’s Bureau, 2016). Despite this high rate of maternal employment, the United States remains one of only two nations in the world without some type of nationally mandated protected paid leave after childbirth (RossinSlater, 2017). Of course, maternal return to employment outside the home shortly after birth is necessary for many families. Because the U.S. lacks federally protected paid time to recover from childbirth and establish breastfeeding, women tend to return to employment much sooner than mothers in other high-income countries (Berger, Hill, & Waldfogel, 2005). Nationally representative studies have found that mothers who return to work before 6 weeks postpartum are at particularly high risk for truncated breastfeeding and are more likely to require supplementation with infant formula (Ogbuanu, Glover, Probst, Liu, & Hussey, 2011). However, the relationship between time off work and successful breastfeeding is not homogeneous. For instance, in Guendelman et al. (2009), early return to employment was associated with shorter breastfeeding durations for mothers of 4- to 5-month-old infants in Southern California, but the association was stronger for mothers who worked in nonmanagerial positions and with inflexible work schedules. Smaller studies conducted within particular organizational settings also point to this heterogeneity. Parsons, Duke, Snow, and Edwards (2009) found no association between time off work and likelihood of breastfeeding for more than 6 months for retrospectively surveyed physician mothers working in Canada. Other researchers have found no associations between time off and breastfeeding duration for mothers of any age children employed by WIC in Los Angeles County (Whaley, Meehan, Lange, Slusser, & Jenks, 2002). One hypothesis is that employed women in certain occupationsdlike in medical offices or social services agenciesdare less likely to experience breastfeeding benefits from time off work than those in other occupationsdlike manufacturing or agricultural work. However, when Kimbro (2006) used data from the low-income women in the Fragile Families study to explicitly test whether occupation type and timing of return to work after childbirth interacted in their associations with breastfeeding duration, they found no such moderation effect. Even though mothers working in manual labor and administrative vocations stopped breastfeeding earlier than those in professional positions or in the service industry, the relationship between time off and breastfeeding duration did not vary across these employment categories. An alternative explanation for the mixed findings across these disparate samples is that the impact of time off work is moderated by other features of the employment context. The stud by Kimbro (2006) suggests that, for low-income families, employment type per se does not moderate the relationship; however, the level of support for breastfeeding that a mother perceives from her employer could plausibly moderate this relationship, putting some mothers at a higher risk for early termination of breastfeeding or for introduction of infant formula owing to early return to work.
Studies have shown that higher perceived support for breastfeeding in the workplace is associated with longer breastfeeding duration (Balkam, Cadwell, & Fein, 2011). Importantly, it is not a given that a lactation-friendly workplace policy in fact leads to greater feelings of support by lactating women who are employed in an organization (Anderson et al., 2015). Different women can experience highly variable levels of support within a single employment context. Therefore, understanding the role of maternal perception is an important component of this work. This perception of support can reference support from superiors or managers, coworkers, or the general climate of support in the worksite or organization (Weber, Janson, Nolan, Wen, & Rissel, 2011). Understanding the role of each kind of support is essential for building policies and programs that can lead to effective changes. Studies suggest that the perception of support within an employment context is modifiable with training and education, and therefore represents a potential lever for change and an important area of research (Zhuang et al., 2018). Additionally, it remains unclear if these unique and potentially interacting features of the return to employment predict important breastfeeding outcomes other than breastfeeding duration. After all, duration is only one way to measure breastfeeding success. Trajectory-based analyses, for instance, are a way to view breastfeeding behaviors as a holistic pattern of change over time, which captures both exclusivity and duration features; however, only rarely do quantitative studies utilize this operationalization of breastfeeding success (Ventura, 2017). Trajectory of breastfeeding behaviors over timedparticularly a trajectory that conforms to both the promoted duration and promoted exclusivity recommendations in a given contextdis perhaps a more policy-relevant conceptualization of breastfeeding success (Whipps, Yoshikawa, & Godfrey, 2018b). A trajectory that most closely maps to biologically normal breastfeeding is also most likely to have lasting implications for maternal and child health (Dettwyler, 2017; Thorley, 2018). For example, in their 2015 metaanalysis, Sankar et al. found evidence that optimal breastfeeding (defined as exclusive breastfeeding for 6 months and continued breastfeeding for two years) was significantly related to infection-related morbidity and infant mortality worldwide. In a similar study, Bartick et al (2017) found that, in the United States specifically, increasing the optimal breastfeeding rate to 90%din other words, 90% of mothers meeting recommendations for both duration and exclusivitydwould prevent more than 3,000 deaths each year. Given the potential impact of promoting biologically normal breastfeeding, understanding the predictors of this type of trajectory is crucial. This study seeks to address these gaps in the literature, as well as to inform breastfeeding-supportive policy development at both the national and organizational levels, by examining the interactive association between features of the return to work and biologically normal breastfeeding behaviors in a large national sample of U.S. mothers. To accomplish this aim, we posed two research questions: (1) How do two features of the transition back to work after childbirth (perception of greater employer support for breastfeeding in the workplace and total length of time off work) independently predict likelihood of membership in an extended, exclusive breastfeeding trajectory during the first year of a child’s life? (2) To what extent do these factors interact in predicting likelihood of membership in this breastfeeding trajectory?
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Methods Participants This study uses data from the Infant Feeding Practices Study II (IFPS-II), a national, longitudinal study conducted by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration focusing on infant feeding behavior (Fein et al., 2008). IFPS-II administered surveys from 2005 to 2007, with a year 6 follow-up survey in 2012 with approximately 51% of the sample, spanning a time frame of prenatal through roughly the child’s sixth year of life. We used a subsample of 1,468 mothers who returned to paid employment within the first year, with a median child age at return to employment of 9.6 weeks. This original sample has a sample size of 3,033 mothers who returned at least the prenatal and neonatal surveys of the 4,902 who were recruited from a national consumer opinion panel. Mothers who qualified to participate in the study were at least 18 years old and healthy at the time of the prenatal questionnaire; infants must have been a healthy full-term or near full-term singleton (35 weeks gestational age) and weighed at least 5 pounds at birth (Fein et al., 2008). The initial IFPS-II mailed surveys in a stamped and addressed return envelope to the mother’s home at 30 weeks gestational age (the prenatal wave), 3 weeks of age (the neonatal wave), and continuing approximately monthly through the child’s first year. The questions focused on the mother’s health and dietary intake, infant feeding practices, sleeping arrangements, and WIC participation. The analytic sample for this study was restricted to mothers who were both employed before giving birth (and responded to the prenatal wave items on perceived workplace support), and who returned to work within the survey timeframe (and thus responded to the survey item on the infant age at return to employment). In total, this subsample is 1,468 participants. Demographic characteristics can be found in Table 1. Institutional review board approval for the study was sought by the working group responsible for the data collection. This study is a secondary analysis of that existing data and is exempt from additional institutional review board review. All data were collected in compliance with the relevant Protection of Human Subjects and Animals in Research, as described by the International Committee of Medical Journal Editors (Fein et al., 2008). Measures Outcome: Predicted probability of assignment to near-exclusive breastfeeding trajectory Based on initial descriptive trajectory analyses (Whipps, Yoshikawa, & Demirci, 2018a), there are four latent subgroups of mother–infant dyads within the larger sample of mothers from the IFPS-II, each following a distinct breastfeeding trajectory. The average breastfeeding trajectory of each group is graphed in Figure 1. The groups were labeled as 1) near-exclusive formula feeding, 2) early weaning combination feeding, 3) later weaning combination feeding, and 4) near-exclusive breastfeeding. The predicted probability of assignment into the nearexclusive breastfeeding trajectory, that is, trajectory 4, was the outcome of interest for this analysis. Each participant was assigned a posterior probability of belonging to this trajectory, ranging from 05 to 100%. Approximately 20% of respondents had more than 90% probability of membership in this trajectory, and approximately 70% of respondents had less than 10% probability of membership (Whipps et al., 2018a).
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Table 1 Participant Characteristics (N ¼ 1,468) Characteristic
%
Time off work (wk) <3 3–6 6.1–9 9.1–12 12.1–16 >16 Workplace support Very supportive Somewhat supportive Not too supportive Not at all supportive Race/ethnicity White Black/African American Hispanic/Latina Asian/Pacific Islander Maternal age (y) 18–24 25–30 >30 Maternal education Less than high school High school or GED Some college or more Household income (per year) <$30,000 $30,000–60,000 >$60,000 WIC Enrollment Lives in the southern United States Married Gestational age Late preterm (35–36.9 weeks) Early term (37–38.9 weeks) Full term (>39 weeks)
6.3 14.6 26.4 19.9 11.2 21.5 38.7 39.8 12.5 9.0 83.5 5.0 5.1 2.3 21.3 37.8 40.9 2.0 15.2 82.8 24.0 39.0 37.0 36.2 29.8 77.7 4.2 30.9 64.9
Abbreviations: GED, high school equivalency; WIC, Special Supplemental Nutrition Program for Women, Infants, and Children.
Predictor: Time off work after childbirth We calculated time off work in number of weeks postpartum using consolidated data from the 3-, 6-, 9-, and 12-month surveys; this calculation was based on the first return to employment after the birth of the target child. The raw variable was significantly positively skewed (skew ¼ 1.86); thus, we used a log transformation for further analysis. After transformation, the variable showed reasonably normal distributional properties (skew ¼ –0.34).
Figure 1. Four distinct breastfeeding trajectories.
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Predictor: Breastfeeding supportive employer During the prenatal wave, respondents reported their perceptions of support for breastfeeding in the workplace on a 1- to 4-point Likert-type scale ranging from 1 (not supportive at all) to 4 (very supportive) in response to the following question: “In your opinion, how supportive of breastfeeding is your place of employment?”. This variable had a negative skew (skew ¼ –0.83), with approximately 25% of participants responding with a 1 or 2. We treated this variable as continuous in analyses. Covariates We controlled for a number of exogenous confounding covariates, each coded from the prenatal wave: maternal race/ ethnicity indicators, years of maternal education (continuous), maternal age in years (continuous), household income (continuous), a dichotomous indicator for Southern region, and child gestational age (continuous, in weeks). We also included as a covariate an indicator for receipt of WIC services at any time postnatally, which was coded using all available waves of data. We dichotomously coded access to paid maternity leave from the prenatal wave, which was used as a covariate in the sensitivity analysis; 41% of respondents indicated access to at least 1 week of paid leave. As a sensitivity analysis, we also checked whether parity (either as a continuous measure, or as an indicator for primiparous birth) would alter the associations. Statistical Analyses We performed a multivariate ordinary least squares regression, predicting the probability of membership in the nearexclusive breastfeeding trajectory with a term for the interaction of log-transformed time off work and perceived support for breastfeeding in the workplace, controlling for confounding covariates. Marginal effects were then probed and graphed. For visualization, we dichotomized workplace support (not at all supportive and not too supportive were characterized as an unsupportive employer, whereas somewhat supportive and very supportive were characterized as a supportive employer), and we plotted the interaction effect. Access to paid maternity leave likely shares a significant amount of variance with both predictors of interest and may in fact represent the mechanism by which either or both influences later breastfeeding behaviors. In other words, the provision of paid leave may be seen by mothers as an aspect of support from the workplace for breastfeeding, and/or may be the mechanism by which time off work influences breastfeeding success. Therefore, simply controlling for access to paid leave would likely be a case of over-controlling for mediating mechanisms (Schisterman, Cole, & Platt, 2009). To address these concerns, we performed sensitivity analyses to test whether accounting for paid maternity leave as a covariate would alter the findings of the main analyses. Results Both time off work and the perception of a breastfeeding supportive workplace were independently positively related to probability of membership in the near-exclusive breastfeeding trajectory (b ¼ 0.16, p ¼ .019, and b ¼ 0.14, p ¼ .004, respectively). The interaction of these two factors was significantly negatively predictive of membership (b ¼ –0.05; p ¼ .029), suggesting an attenuation effect. In other words, at higher levels of perceived workplace support for breastfeeding, the predictive positive association between time off work and probability of membership
in the near-exclusive breastfeeding trajectory was reduced. See Table 2 for complete results. For mothers who indicated that their workplaces were not at all supportive or not too supportive, the association between time off work and probability of membership in the near-exclusive breastfeeding trajectory is significantly positive (b ¼ 0.12, p ¼ .018 and b ¼ 0.07, p ¼ .022, respectively). For women who perceived their workplaces as somewhat supportive or very supportive, there was no significant relationship between time off work and trajectory membership (b ¼ .027, p ¼ .155 and b ¼ – 0.018, p ¼ .454, respectively). See Figure 2 for a visualization of the moderation effect by dichotomous workplace support. Sensitivity Analysis Upon the addition of paid leave to the model, the main effects and interaction effects remained essentially the same: b (log time off work) ¼ 0.16, p ¼ .023; b (perception of support) ¼ 0.13, p ¼ .006; b (interaction) ¼ –0.04, p ¼ .039. The covariate itself was marginally negatively associated with membership in the near-exclusive trajectory (b ¼ –0.04; p ¼ .086). As an additional check, parity was included as a covariate to assess whether it altered the results. The addition of paritydas either an indicator for first-time motherhood, or as a continuous measure of number of previous birthsddid not alter the direction, magnitude, or significance of the any of the interpreted associations. Discussion To our knowledge, this is the first study to quantitatively examine the interactive associations between two features of mothers’ return to employment on later breastfeeding trajectories in the United States. We found that total time off work after the birth of a child predicted increased probability of following a breastfeeding trajectory characterized by nearexclusive breastfeeding for the first year. This association was attenuated, however, by the perception of workplace support for breastfeeding: the positive relationship between time off and trajectory membership was significant only for mothers who perceived their workplaces to be unsupportive of breastfeeding.
Table 2 Prediction of Probability of Membership in Near-Exclusive Breastfeeding Trajectory (N ¼ 1,031) Coefficient Predictors Time off work (log transformed) Perception of workplace support Interaction Time off * support Covariates Black/African American Hispanic/Latina Asian and Pacific Islander Maternal education Maternal age Household income Marital status Infant gestational age WIC enrollment Southern resident
Standard Error
p Value
0.163 0.135
0.07 0.05
.019 .004
0.045
0.02
.029
0.014 0.083 0.179 0.100 0.001 0.011 0.082 0.028 0.042 0.063
0.06 0.06 0.08 0.02 0.00 0.00 0.03 0.01 0.03 0.03
.825 .138 .019 .000 .703 .001 .016 .005 .227 .023
Abbreviation: WIC, Special Supplemental Nutrition Program for Women, Infants, and Children.
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Figure 2. Predicted membership in exclusive breastfeeding trajectory.
It is important to note that although this interaction effect is significant, the independent predictors of time off work and perceived workplace support remain significant in the full model as well. This pattern holds even when paid maternity leave, a potential mediator, is included as a covariate. Therefore, it would not be appropriate to conclude that if all women had support from employers that time off work would not be an important factor in breastfeeding success; nor would it be appropriate to conclude that if all women had adequate time off work to recover from childbirth, that they would not benefit from workplace support in combining breastfeeding with paid employment. This moderation finding merely allows for increased understanding of these two determinants of breastfeeding over time, and may inform the targeting of specific kinds of interventions to groups of mothers who may benefit most from them. Furthermore, because moderation analyses are in a sense symmetrical, it is not possible to know whether this finding indicates that breastfeeding support is particularly important for mothers returning to work early, or whether adequate time off work is particularly important for mothers with unsupportive employers. A review of qualitative and quantitative descriptive work suggests that both may be true (Johnston & Esposito, 2007). Regardless, knowing which confluence of contextual factors puts mothers most at risk for truncated breastfeeding trajectories is crucial for targeting policy and intervention efforts. Our findings suggest that those most at risk are mothers who have both low employer support and take fewer weeks off work after the birth of their child. A surprising finding of the current study is that the relationship between higher workplace support and membership in a near-exclusive breastfeeding trajectory seems to be negative for respondents who take off more than 16 weeks after childbirth. This may be a function of our particular sample; only approximately 21% of mothers who returned to paid employment in the first year did so after 16 weeks, and one-half of our sample returned before 10 weeks. It is plausible that there is a qualitatively different relationship between time off work, employer support, and breastfeeding trajectory at this end of the distribution, perhaps suggesting a nonlinear relationship. Further studies could examine this type of relationship using semiparametric analytic methods or using samples that returned to work later than mothers in the IFPS-II to probe this surprising finding.
Limitations and Future Directions The data used was from the IFPS-II, which is a dataset that was originally collected from 2005 to 2007. Although these are
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the only national data currently available with which this kind of trajectory analysis can be conducted, the age of the data represents a limitation for the current study, because the proportions of mothers in each trajectory or the overall level of support for breastfeeding may have shifted since they were collected. Future studies should use newer data to examine whether these patterns of association can be replicated, and explicitly test whether state-level parental leave policies and the 2010 Affordable Care Act has altered these findings. Additionally, in the IFPS-II, workplace support for breastfeeding is measured with only a single item. Although this item has face validity for measuring maternal perception of workplace support, it is unclear how reflective of actual workplace context (policies, interpersonal communications, etc.) this perception might be. Finally, the current study examines the interactive predictors of only one breastfeeding trajectory (near-exclusive breastfeeding with slow weaning for the first year postpartum). Understanding the associations between time off work, workplace support, and other types of infant feeding patterns is an important future direction. Implications for Practice and/or Policy Interventions aimed at increasing employer support for breastfeeding have sprung up in several places over the past decade. Some such programs exist at the national leveldfor instance, Australia has established a Breastfeeding Friendly Workplace Accreditation program that aims to identify and celebrate worksites with high levels of instrumental support for lactating employees (Croker & Eldrige, 2005). The Patient Protection and Affordable Care Act of 2010 mandated that U.S. employers must accommodate lactating employees; however, the mandate lacks an enforcement provision and does not apply to approximately 25% of U.S. employers (Lennon & Willis, 2017; U.S. Department of Labor, 2010). Additionally, sufficient data do not exist at the national level that could enable the evaluation of the impact of the lactation protection provisions of the Patient Protection and Affordable Care Act (Hawkins, Noble, & Baum, 2018). Furthermore, these policies do not necessarily lead to a feeling of support for lactating women in the workplace and have in some cases led to backlash and discrimination (Morris, Lee, & Williams, 2019). Large, national corporations have also endeavored to codify breastfeeding support by providing access to lactation consultants before and after birth, purchasing pumps and pump parts, and designating an adequate space for lactating mothers to express and store breast milk (e.g., Cardenas & Major, 2005; CIGNA, 2000). However, rigorous evaluations of these employer-support programs are rare (Abdulwadud & Snow, 2012; Dinour & Szaro, 2017). More research on the effectiveness of lactation protection programs is necessary before they can be brought to scale. In other words, we need more information about whether these system-level changes result in higher perceptions of support among breastfeeding workers, and whether they have an impact on the likelihood of engaging in breastfeeding behaviors that are most likely to have a positive impact on infant and maternal health (i.e., sustained, exclusive breastfeeding). Findings from the current study also suggest future policy directions. Given the rapidly changing state- and national-level family leave policy landscape in the United States, it is crucial for advocacy groups to be aware of who is most at risk of not meeting breastfeeding guidelines and how best to reach those dyads. This study suggests that mothers who do not perceive their workplaces as supportive are most vulnerable to the risks of
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early return to employment. This perception of support may be linked to occupation type, occupational prestige, or income in complex ways. Future research is necessary to identify which mothers, in which professions, are most likely to perceive low breastfeeding support from their employers so that advocacy efforts can efficiently target those populations for intervention development and policy change effort. Knowing which confluence of contextual factors puts mothers most at risk for truncated breastfeeding trajectories is crucial for targeting policy and intervention efforts.
Conclusions It is well-documented that combining breastfeeding with return to employment is difficult for many mothers in the United States. Few working mothers are able to establish a trajectory of breastfeeding over the first year that meets both the duration and exclusivity guidelines set forth by the AAP (*American Academy of Pediatrics, 2012; Eidelman, 2012). We found that greater time off work after childbirth predicted higher likelihood of membership in such a trajectory, but only for mothers who perceived their employers to be unsupportive of breastfeeding in the workplace. This finding has implications for both intervention development and policy development in the United States.
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Optimal breastfeeding practices and infant and child mortality: A systematic review and meta-analysis. Acta Paediatrica, 104, 3–13. Schisterman, E. F., Cole, S. R., & Platt, R. W. (2009). Overadjustment bias and unnecessary adjustment in epidemiologic studies. Epidemiology, 20(4), 488– 495. Thorley, V. (2018). Is breastfeeding ‘normal’? Using the right language for breastfeeding. Midwifery, 69, 39–44. U.S. Department of Labor: Women’s Bureau. (2016). Working mothers issue brief. Available: www.dol.gov/wb/resources/WB_WorkingMothers _508_ FinalJune13.pdf. Accessed: October 10, 2018. U.S. Department of Labor. (2010). Section 7(r) of the Fair Labor Standards ActdBreak Time for Nursing Mothers provision. Available: www.dol.gov/ whd/nursingmothers/Sec7rFLSA_btnm.htm. Accessed: October 7, 2018. Ventura, A. K. (2017). Developmental trajectories of bottle-feeding during infancy and their association with weight gain. Journal of Developmental & Behavioral Pediatrics, 38(2), 109–119. Weber, D., Janson, A., Nolan, M., Wen, L. M., & Rissel, C. (2011). Female employees’ perceptions of organisational support for breastfeeding at work: findings from an Australian health service workplace. International Breastfeeding Journal, 6(1), 19–25. Whaley, S., Meehan, K., Lange, L., Slusser, W., & Jenks, E. (2002). Predictors of breastfeeding duration for employees of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Journal of American Dietetic Association, 102(9), 1290–1293. Whipps, M. D. M. (2017). Education attainment and parity explain the relationship between maternal age and breastfeeding duration in U.S. mothers. Journal of Human Lactation, 33(1), 220–224. Whipps, M. D. M., Yoshikawa, H., & Demirci, J. (2018a). Latent trajectories of infant breastmilk consumption in the United States. Maternal Child Nutrition, 15, e12655. Whipps, M. D. M., Yoshikawa, H., & Godfrey, E. (2018b). The maternal ecology of breastfeeding: A life course developmental perspective. Human Development, 61(2), 71–95. Zhuang, J., Bresnahan, M. J., Yan, X., Zhu, Y., Goldbort, J., & Bogdan-Lovis, E. (2018). Keep doing the good work: Impact of coworker and community support on continuation of breastfeeding. Health Communication. United Kingdom: Taylor & Francis, 1–9.
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Author Descriptions Mackenzie D.M. Whipps, BSc CLC, is a doctoral candidate in Psychology and Social Intervention at NYU Steinhardt School of Culture, Education, and Human Development. She has spent more than 10 years as a birth and postpartum doula, childbirth educator, and lactation counselor.
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Julia Honoroff, BA, is a Junior Research Scientist at New York University. Her research interests overlap psychology and social policy, specifically related to prevention and intervention research that improves access to services and care for low-income and underserved children and families.
www.whijournal.com
Original article
Time Off Work After Childbirth and Breastfeeding Supportive Workplaces: Associations with Near-Exclusive Breastfeeding Trajectory Membership Mackenzie D.M. Whipps, BSc, CLC a, Julia Honoroff, BA b,* a
New York University Steinhardt School of Culture, Education, and Human Development, New York, New York Institute of Human Development and Social Change, New York University Steinhardt School of Culture, Education, and Human Development, New York, New York b
Article history: Received 8 January 2019; Received in revised form 19 August 2019; Accepted 22 August 2019
a b s t r a c t Objective: We aimed to determine whether the association between time off work and a near-exclusive breastfeeding trajectory is moderated by perceived employer support for breastfeeding. Methods: We conducted a secondary analysis of working mothers (n ¼ 1,468) from the Infant Feeding Practices Study II, a longitudinal observational (2005–2007) study of U.S. infant feeding behaviors. Previous studies have found four latent infant feeding subgroups in the Infant Feeding Practices Study II sample, each following a distinct breastfeeding intensity trajectory. Multivariate least-squares regression was conducted to estimate whether time off work after delivery predicted increased membership in the subgroup characterized by near-exclusive breastfeeding, and whether this association was moderated by perceived employer support for workplace breastfeeding. Results: Both time off work and perception of more breastfeeding support were independently, positively related to probability of membership in the near-exclusive breastfeeding trajectory (b ¼ 0.16, p ¼ .019, and b ¼ 0.14, p ¼ .004, respectively). The interaction of these two factors suggests an attenuation effect. The addition of paid leave to the model did not change the estimates. Conclusion: The positive relationship between time off and trajectory membership was significant only for mothers who perceived their workplaces to be unsupportive of breastfeeding. Ó 2019 Jacobs Institute of Women's Health. Published by Elsevier Inc.
It is well-established that absent or truncated breastfeeding adversely effects maternal health and well-being, increasing the risks of some reproductive cancers and other noncommunicable diseases like diabetes (Chowdhury et al., 2015). Although various national health organizations promote and recommend exclusive breastfeeding for 6 months and continued breastfeeding for at least 1 year (American Academy of Pediatrics, 2012), a large proportion of U.S. mothers do not meet these benchmarks
Funding Statement: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors have no conflicts of interest to declare. * Correspondence to: Julia Honoroff, BA, New York University Steinhardt School of Culture, Institute of Human Development and Social Change, 627 Broadway, Room 711, New York, NY 10012. Phone: 201-655-1963. E-mail address: [email protected] (J. Honoroff).
(Bartick et al., 2017; Centers for Disease Control and Prevention, 2016). Decades of research has sought to understand the predictors of breastfeeding in the United States in an effort to support breastfeeding success. Exposure to racism, especially as an African American or Latina mother and especially in the U.S. South, has been shown to predict shorter breastfeeding durations and/ or lower breastfeeding exclusivity (Griswold et al., 2018; Ma & Magnus, 2012). Poverty and enrollment in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) have a complex relationship to breastfeeding success as well; formal WIC policies seem to promote exclusive breastfeeding, but common practices by WIC counselors and implementation of those policies may actually encourage infant formula use (Baumgartel & Spatz, 2013). Younger maternal age and lower maternal education, as well as certain infant health markersdsuch as late preterm or early term birth as compared
1049-3867/$ - see front matter Ó 2019 Jacobs Institute of Women's Health. Published by Elsevier Inc. https://doi.org/10.1016/j.whi.2019.08.006
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to full term birthdare also risk factors for early termination of breastfeeding (Radtke, 2011; Whipps, 2017). The context of a mother’s return to employment appears to one primary factor in long-term breastfeeding success for U.S. mothers. In the United States, approximately one-half of the women in the workforce are of childbearing age (between ages 16 and 44), and approximately 60% of mothers with children younger than 3 years old are employed full time (U.S. Department of Labor: Women’s Bureau, 2016). Despite this high rate of maternal employment, the United States remains one of only two nations in the world without some type of nationally mandated protected paid leave after childbirth (RossinSlater, 2017). Of course, maternal return to employment outside the home shortly after birth is necessary for many families. Because the U.S. lacks federally protected paid time to recover from childbirth and establish breastfeeding, women tend to return to employment much sooner than mothers in other high-income countries (Berger, Hill, & Waldfogel, 2005). Nationally representative studies have found that mothers who return to work before 6 weeks postpartum are at particularly high risk for truncated breastfeeding and are more likely to require supplementation with infant formula (Ogbuanu, Glover, Probst, Liu, & Hussey, 2011). However, the relationship between time off work and successful breastfeeding is not homogeneous. For instance, in Guendelman et al. (2009), early return to employment was associated with shorter breastfeeding durations for mothers of 4- to 5-month-old infants in Southern California, but the association was stronger for mothers who worked in nonmanagerial positions and with inflexible work schedules. Smaller studies conducted within particular organizational settings also point to this heterogeneity. Parsons, Duke, Snow, and Edwards (2009) found no association between time off work and likelihood of breastfeeding for more than 6 months for retrospectively surveyed physician mothers working in Canada. Other researchers have found no associations between time off and breastfeeding duration for mothers of any age children employed by WIC in Los Angeles County (Whaley, Meehan, Lange, Slusser, & Jenks, 2002). One hypothesis is that employed women in certain occupationsdlike in medical offices or social services agenciesdare less likely to experience breastfeeding benefits from time off work than those in other occupationsdlike manufacturing or agricultural work. However, when Kimbro (2006) used data from the low-income women in the Fragile Families study to explicitly test whether occupation type and timing of return to work after childbirth interacted in their associations with breastfeeding duration, they found no such moderation effect. Even though mothers working in manual labor and administrative vocations stopped breastfeeding earlier than those in professional positions or in the service industry, the relationship between time off and breastfeeding duration did not vary across these employment categories. An alternative explanation for the mixed findings across these disparate samples is that the impact of time off work is moderated by other features of the employment context. The stud by Kimbro (2006) suggests that, for low-income families, employment type per se does not moderate the relationship; however, the level of support for breastfeeding that a mother perceives from her employer could plausibly moderate this relationship, putting some mothers at a higher risk for early termination of breastfeeding or for introduction of infant formula owing to early return to work.
Studies have shown that higher perceived support for breastfeeding in the workplace is associated with longer breastfeeding duration (Balkam, Cadwell, & Fein, 2011). Importantly, it is not a given that a lactation-friendly workplace policy in fact leads to greater feelings of support by lactating women who are employed in an organization (Anderson et al., 2015). Different women can experience highly variable levels of support within a single employment context. Therefore, understanding the role of maternal perception is an important component of this work. This perception of support can reference support from superiors or managers, coworkers, or the general climate of support in the worksite or organization (Weber, Janson, Nolan, Wen, & Rissel, 2011). Understanding the role of each kind of support is essential for building policies and programs that can lead to effective changes. Studies suggest that the perception of support within an employment context is modifiable with training and education, and therefore represents a potential lever for change and an important area of research (Zhuang et al., 2018). Additionally, it remains unclear if these unique and potentially interacting features of the return to employment predict important breastfeeding outcomes other than breastfeeding duration. After all, duration is only one way to measure breastfeeding success. Trajectory-based analyses, for instance, are a way to view breastfeeding behaviors as a holistic pattern of change over time, which captures both exclusivity and duration features; however, only rarely do quantitative studies utilize this operationalization of breastfeeding success (Ventura, 2017). Trajectory of breastfeeding behaviors over timedparticularly a trajectory that conforms to both the promoted duration and promoted exclusivity recommendations in a given contextdis perhaps a more policy-relevant conceptualization of breastfeeding success (Whipps, Yoshikawa, & Godfrey, 2018b). A trajectory that most closely maps to biologically normal breastfeeding is also most likely to have lasting implications for maternal and child health (Dettwyler, 2017; Thorley, 2018). For example, in their 2015 metaanalysis, Sankar et al. found evidence that optimal breastfeeding (defined as exclusive breastfeeding for 6 months and continued breastfeeding for two years) was significantly related to infection-related morbidity and infant mortality worldwide. In a similar study, Bartick et al (2017) found that, in the United States specifically, increasing the optimal breastfeeding rate to 90%din other words, 90% of mothers meeting recommendations for both duration and exclusivitydwould prevent more than 3,000 deaths each year. Given the potential impact of promoting biologically normal breastfeeding, understanding the predictors of this type of trajectory is crucial. This study seeks to address these gaps in the literature, as well as to inform breastfeeding-supportive policy development at both the national and organizational levels, by examining the interactive association between features of the return to work and biologically normal breastfeeding behaviors in a large national sample of U.S. mothers. To accomplish this aim, we posed two research questions: (1) How do two features of the transition back to work after childbirth (perception of greater employer support for breastfeeding in the workplace and total length of time off work) independently predict likelihood of membership in an extended, exclusive breastfeeding trajectory during the first year of a child’s life? (2) To what extent do these factors interact in predicting likelihood of membership in this breastfeeding trajectory?
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Methods Participants This study uses data from the Infant Feeding Practices Study II (IFPS-II), a national, longitudinal study conducted by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration focusing on infant feeding behavior (Fein et al., 2008). IFPS-II administered surveys from 2005 to 2007, with a year 6 follow-up survey in 2012 with approximately 51% of the sample, spanning a time frame of prenatal through roughly the child’s sixth year of life. We used a subsample of 1,468 mothers who returned to paid employment within the first year, with a median child age at return to employment of 9.6 weeks. This original sample has a sample size of 3,033 mothers who returned at least the prenatal and neonatal surveys of the 4,902 who were recruited from a national consumer opinion panel. Mothers who qualified to participate in the study were at least 18 years old and healthy at the time of the prenatal questionnaire; infants must have been a healthy full-term or near full-term singleton (35 weeks gestational age) and weighed at least 5 pounds at birth (Fein et al., 2008). The initial IFPS-II mailed surveys in a stamped and addressed return envelope to the mother’s home at 30 weeks gestational age (the prenatal wave), 3 weeks of age (the neonatal wave), and continuing approximately monthly through the child’s first year. The questions focused on the mother’s health and dietary intake, infant feeding practices, sleeping arrangements, and WIC participation. The analytic sample for this study was restricted to mothers who were both employed before giving birth (and responded to the prenatal wave items on perceived workplace support), and who returned to work within the survey timeframe (and thus responded to the survey item on the infant age at return to employment). In total, this subsample is 1,468 participants. Demographic characteristics can be found in Table 1. Institutional review board approval for the study was sought by the working group responsible for the data collection. This study is a secondary analysis of that existing data and is exempt from additional institutional review board review. All data were collected in compliance with the relevant Protection of Human Subjects and Animals in Research, as described by the International Committee of Medical Journal Editors (Fein et al., 2008). Measures Outcome: Predicted probability of assignment to near-exclusive breastfeeding trajectory Based on initial descriptive trajectory analyses (Whipps, Yoshikawa, & Demirci, 2018a), there are four latent subgroups of mother–infant dyads within the larger sample of mothers from the IFPS-II, each following a distinct breastfeeding trajectory. The average breastfeeding trajectory of each group is graphed in Figure 1. The groups were labeled as 1) near-exclusive formula feeding, 2) early weaning combination feeding, 3) later weaning combination feeding, and 4) near-exclusive breastfeeding. The predicted probability of assignment into the nearexclusive breastfeeding trajectory, that is, trajectory 4, was the outcome of interest for this analysis. Each participant was assigned a posterior probability of belonging to this trajectory, ranging from 05 to 100%. Approximately 20% of respondents had more than 90% probability of membership in this trajectory, and approximately 70% of respondents had less than 10% probability of membership (Whipps et al., 2018a).
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Table 1 Participant Characteristics (N ¼ 1,468) Characteristic
%
Time off work (wk) <3 3–6 6.1–9 9.1–12 12.1–16 >16 Workplace support Very supportive Somewhat supportive Not too supportive Not at all supportive Race/ethnicity White Black/African American Hispanic/Latina Asian/Pacific Islander Maternal age (y) 18–24 25–30 >30 Maternal education Less than high school High school or GED Some college or more Household income (per year) <$30,000 $30,000–60,000 >$60,000 WIC Enrollment Lives in the southern United States Married Gestational age Late preterm (35–36.9 weeks) Early term (37–38.9 weeks) Full term (>39 weeks)
6.3 14.6 26.4 19.9 11.2 21.5 38.7 39.8 12.5 9.0 83.5 5.0 5.1 2.3 21.3 37.8 40.9 2.0 15.2 82.8 24.0 39.0 37.0 36.2 29.8 77.7 4.2 30.9 64.9
Abbreviations: GED, high school equivalency; WIC, Special Supplemental Nutrition Program for Women, Infants, and Children.
Predictor: Time off work after childbirth We calculated time off work in number of weeks postpartum using consolidated data from the 3-, 6-, 9-, and 12-month surveys; this calculation was based on the first return to employment after the birth of the target child. The raw variable was significantly positively skewed (skew ¼ 1.86); thus, we used a log transformation for further analysis. After transformation, the variable showed reasonably normal distributional properties (skew ¼ –0.34).
Figure 1. Four distinct breastfeeding trajectories.
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Predictor: Breastfeeding supportive employer During the prenatal wave, respondents reported their perceptions of support for breastfeeding in the workplace on a 1- to 4-point Likert-type scale ranging from 1 (not supportive at all) to 4 (very supportive) in response to the following question: “In your opinion, how supportive of breastfeeding is your place of employment?”. This variable had a negative skew (skew ¼ –0.83), with approximately 25% of participants responding with a 1 or 2. We treated this variable as continuous in analyses. Covariates We controlled for a number of exogenous confounding covariates, each coded from the prenatal wave: maternal race/ ethnicity indicators, years of maternal education (continuous), maternal age in years (continuous), household income (continuous), a dichotomous indicator for Southern region, and child gestational age (continuous, in weeks). We also included as a covariate an indicator for receipt of WIC services at any time postnatally, which was coded using all available waves of data. We dichotomously coded access to paid maternity leave from the prenatal wave, which was used as a covariate in the sensitivity analysis; 41% of respondents indicated access to at least 1 week of paid leave. As a sensitivity analysis, we also checked whether parity (either as a continuous measure, or as an indicator for primiparous birth) would alter the associations. Statistical Analyses We performed a multivariate ordinary least squares regression, predicting the probability of membership in the nearexclusive breastfeeding trajectory with a term for the interaction of log-transformed time off work and perceived support for breastfeeding in the workplace, controlling for confounding covariates. Marginal effects were then probed and graphed. For visualization, we dichotomized workplace support (not at all supportive and not too supportive were characterized as an unsupportive employer, whereas somewhat supportive and very supportive were characterized as a supportive employer), and we plotted the interaction effect. Access to paid maternity leave likely shares a significant amount of variance with both predictors of interest and may in fact represent the mechanism by which either or both influences later breastfeeding behaviors. In other words, the provision of paid leave may be seen by mothers as an aspect of support from the workplace for breastfeeding, and/or may be the mechanism by which time off work influences breastfeeding success. Therefore, simply controlling for access to paid leave would likely be a case of over-controlling for mediating mechanisms (Schisterman, Cole, & Platt, 2009). To address these concerns, we performed sensitivity analyses to test whether accounting for paid maternity leave as a covariate would alter the findings of the main analyses. Results Both time off work and the perception of a breastfeeding supportive workplace were independently positively related to probability of membership in the near-exclusive breastfeeding trajectory (b ¼ 0.16, p ¼ .019, and b ¼ 0.14, p ¼ .004, respectively). The interaction of these two factors was significantly negatively predictive of membership (b ¼ –0.05; p ¼ .029), suggesting an attenuation effect. In other words, at higher levels of perceived workplace support for breastfeeding, the predictive positive association between time off work and probability of membership
in the near-exclusive breastfeeding trajectory was reduced. See Table 2 for complete results. For mothers who indicated that their workplaces were not at all supportive or not too supportive, the association between time off work and probability of membership in the near-exclusive breastfeeding trajectory is significantly positive (b ¼ 0.12, p ¼ .018 and b ¼ 0.07, p ¼ .022, respectively). For women who perceived their workplaces as somewhat supportive or very supportive, there was no significant relationship between time off work and trajectory membership (b ¼ .027, p ¼ .155 and b ¼ – 0.018, p ¼ .454, respectively). See Figure 2 for a visualization of the moderation effect by dichotomous workplace support. Sensitivity Analysis Upon the addition of paid leave to the model, the main effects and interaction effects remained essentially the same: b (log time off work) ¼ 0.16, p ¼ .023; b (perception of support) ¼ 0.13, p ¼ .006; b (interaction) ¼ –0.04, p ¼ .039. The covariate itself was marginally negatively associated with membership in the near-exclusive trajectory (b ¼ –0.04; p ¼ .086). As an additional check, parity was included as a covariate to assess whether it altered the results. The addition of paritydas either an indicator for first-time motherhood, or as a continuous measure of number of previous birthsddid not alter the direction, magnitude, or significance of the any of the interpreted associations. Discussion To our knowledge, this is the first study to quantitatively examine the interactive associations between two features of mothers’ return to employment on later breastfeeding trajectories in the United States. We found that total time off work after the birth of a child predicted increased probability of following a breastfeeding trajectory characterized by nearexclusive breastfeeding for the first year. This association was attenuated, however, by the perception of workplace support for breastfeeding: the positive relationship between time off and trajectory membership was significant only for mothers who perceived their workplaces to be unsupportive of breastfeeding.
Table 2 Prediction of Probability of Membership in Near-Exclusive Breastfeeding Trajectory (N ¼ 1,031) Coefficient Predictors Time off work (log transformed) Perception of workplace support Interaction Time off * support Covariates Black/African American Hispanic/Latina Asian and Pacific Islander Maternal education Maternal age Household income Marital status Infant gestational age WIC enrollment Southern resident
Standard Error
p Value
0.163 0.135
0.07 0.05
.019 .004
0.045
0.02
.029
0.014 0.083 0.179 0.100 0.001 0.011 0.082 0.028 0.042 0.063
0.06 0.06 0.08 0.02 0.00 0.00 0.03 0.01 0.03 0.03
.825 .138 .019 .000 .703 .001 .016 .005 .227 .023
Abbreviation: WIC, Special Supplemental Nutrition Program for Women, Infants, and Children.
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Figure 2. Predicted membership in exclusive breastfeeding trajectory.
It is important to note that although this interaction effect is significant, the independent predictors of time off work and perceived workplace support remain significant in the full model as well. This pattern holds even when paid maternity leave, a potential mediator, is included as a covariate. Therefore, it would not be appropriate to conclude that if all women had support from employers that time off work would not be an important factor in breastfeeding success; nor would it be appropriate to conclude that if all women had adequate time off work to recover from childbirth, that they would not benefit from workplace support in combining breastfeeding with paid employment. This moderation finding merely allows for increased understanding of these two determinants of breastfeeding over time, and may inform the targeting of specific kinds of interventions to groups of mothers who may benefit most from them. Furthermore, because moderation analyses are in a sense symmetrical, it is not possible to know whether this finding indicates that breastfeeding support is particularly important for mothers returning to work early, or whether adequate time off work is particularly important for mothers with unsupportive employers. A review of qualitative and quantitative descriptive work suggests that both may be true (Johnston & Esposito, 2007). Regardless, knowing which confluence of contextual factors puts mothers most at risk for truncated breastfeeding trajectories is crucial for targeting policy and intervention efforts. Our findings suggest that those most at risk are mothers who have both low employer support and take fewer weeks off work after the birth of their child. A surprising finding of the current study is that the relationship between higher workplace support and membership in a near-exclusive breastfeeding trajectory seems to be negative for respondents who take off more than 16 weeks after childbirth. This may be a function of our particular sample; only approximately 21% of mothers who returned to paid employment in the first year did so after 16 weeks, and one-half of our sample returned before 10 weeks. It is plausible that there is a qualitatively different relationship between time off work, employer support, and breastfeeding trajectory at this end of the distribution, perhaps suggesting a nonlinear relationship. Further studies could examine this type of relationship using semiparametric analytic methods or using samples that returned to work later than mothers in the IFPS-II to probe this surprising finding.
Limitations and Future Directions The data used was from the IFPS-II, which is a dataset that was originally collected from 2005 to 2007. Although these are
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the only national data currently available with which this kind of trajectory analysis can be conducted, the age of the data represents a limitation for the current study, because the proportions of mothers in each trajectory or the overall level of support for breastfeeding may have shifted since they were collected. Future studies should use newer data to examine whether these patterns of association can be replicated, and explicitly test whether state-level parental leave policies and the 2010 Affordable Care Act has altered these findings. Additionally, in the IFPS-II, workplace support for breastfeeding is measured with only a single item. Although this item has face validity for measuring maternal perception of workplace support, it is unclear how reflective of actual workplace context (policies, interpersonal communications, etc.) this perception might be. Finally, the current study examines the interactive predictors of only one breastfeeding trajectory (near-exclusive breastfeeding with slow weaning for the first year postpartum). Understanding the associations between time off work, workplace support, and other types of infant feeding patterns is an important future direction. Implications for Practice and/or Policy Interventions aimed at increasing employer support for breastfeeding have sprung up in several places over the past decade. Some such programs exist at the national leveldfor instance, Australia has established a Breastfeeding Friendly Workplace Accreditation program that aims to identify and celebrate worksites with high levels of instrumental support for lactating employees (Croker & Eldrige, 2005). The Patient Protection and Affordable Care Act of 2010 mandated that U.S. employers must accommodate lactating employees; however, the mandate lacks an enforcement provision and does not apply to approximately 25% of U.S. employers (Lennon & Willis, 2017; U.S. Department of Labor, 2010). Additionally, sufficient data do not exist at the national level that could enable the evaluation of the impact of the lactation protection provisions of the Patient Protection and Affordable Care Act (Hawkins, Noble, & Baum, 2018). Furthermore, these policies do not necessarily lead to a feeling of support for lactating women in the workplace and have in some cases led to backlash and discrimination (Morris, Lee, & Williams, 2019). Large, national corporations have also endeavored to codify breastfeeding support by providing access to lactation consultants before and after birth, purchasing pumps and pump parts, and designating an adequate space for lactating mothers to express and store breast milk (e.g., Cardenas & Major, 2005; CIGNA, 2000). However, rigorous evaluations of these employer-support programs are rare (Abdulwadud & Snow, 2012; Dinour & Szaro, 2017). More research on the effectiveness of lactation protection programs is necessary before they can be brought to scale. In other words, we need more information about whether these system-level changes result in higher perceptions of support among breastfeeding workers, and whether they have an impact on the likelihood of engaging in breastfeeding behaviors that are most likely to have a positive impact on infant and maternal health (i.e., sustained, exclusive breastfeeding). Findings from the current study also suggest future policy directions. Given the rapidly changing state- and national-level family leave policy landscape in the United States, it is crucial for advocacy groups to be aware of who is most at risk of not meeting breastfeeding guidelines and how best to reach those dyads. This study suggests that mothers who do not perceive their workplaces as supportive are most vulnerable to the risks of
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early return to employment. This perception of support may be linked to occupation type, occupational prestige, or income in complex ways. Future research is necessary to identify which mothers, in which professions, are most likely to perceive low breastfeeding support from their employers so that advocacy efforts can efficiently target those populations for intervention development and policy change effort. Knowing which confluence of contextual factors puts mothers most at risk for truncated breastfeeding trajectories is crucial for targeting policy and intervention efforts.
Conclusions It is well-documented that combining breastfeeding with return to employment is difficult for many mothers in the United States. Few working mothers are able to establish a trajectory of breastfeeding over the first year that meets both the duration and exclusivity guidelines set forth by the AAP (*American Academy of Pediatrics, 2012; Eidelman, 2012). We found that greater time off work after childbirth predicted higher likelihood of membership in such a trajectory, but only for mothers who perceived their employers to be unsupportive of breastfeeding in the workplace. This finding has implications for both intervention development and policy development in the United States.
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Author Descriptions Mackenzie D.M. Whipps, BSc CLC, is a doctoral candidate in Psychology and Social Intervention at NYU Steinhardt School of Culture, Education, and Human Development. She has spent more than 10 years as a birth and postpartum doula, childbirth educator, and lactation counselor.
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Julia Honoroff, BA, is a Junior Research Scientist at New York University. Her research interests overlap psychology and social policy, specifically related to prevention and intervention research that improves access to services and care for low-income and underserved children and families.