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A nation‐wide study on the common reasons for infant formula supplementation among healthy, term, breastfed infants in US hospitals

Abstract In‐hospital infant formula supplementation of breastfed infants reduces breastfeeding duration, yet little is known about common reasons for infant formula supplementation. We examined the three most common reasons for in‐hospital infant formula supplementation of healthy, term, breastfed infants in the US reported by hospital staff. Hospital data were obtained from the 2018 Maternity Practices in Infant Nutrition and Care survey (n = 2045), which is completed by hospital staff. An open‐ended question on the top three reasons for in‐hospital infant formula supplementation was analyzed using thematic qualitative analysis and the frequencies for each reason were reported. The top three most common reasons for in‐hospital infant formula supplementation reported by hospital staff included medical indications (70.0%); maternal request/preference/feelings (55.9%); lactation management‐related issues (51.3%); physical but non‐medically indicated reasons (36.1%); social influences (18.8%); perceived cultural/societal/demographic factors (8.2%) and medical staff/institutional practices (4.7%). These findings suggest that a variety of factors should be considered to address unnecessary infant formula supplementation. Lactation management support delivered in a timely and culturally sensitive manner and targeted to mother‐infant dyads with potential medical and physical indications may reduce unnecessary in‐hospital infant formula supplementation.


| INTRODUCTION
Exclusive breastfeeding for the first 6 months of life has been established as the normative standard for infant feeding, with continued breastfeeding along with complementary foods for 1 year or beyond by the American Academy of Pediatrics (Eidelman, 2012)  Human Services, 2020). The introduction of infant formula is associated with adverse health consequences for infants including increased risks for infectious diseases (e.g., respiratory infections, gastrointestinal infections, otitis media, etc.) and noninfectious disease (e.g., sudden infant death syndrome, allergic disease, etc.) (Eidelman, 2012;Victora et al., 2016). National Healthy People 2030 goals are to increase the proportion of infants who are exclusively breastfed through 6 months to 42% and to increase the proportion of infants who are breastfed at 1 year to 54% (Office of Disease Prevention and Health Promotion, 2020). In the United States, 84% of children initiate breastfeeding; however, only 26% exclusively breastfeed for 6 months and 35% breastfeed for 1 year (Centers for Disease Control and Prevention, 2020a). In-hospital exclusive breastfeeding during the days immediately after birth has been shown to be important for continued duration (Chantry et al., 2014). Yet Infant formula supplementation of breastfed newborns often occurs during the intrapartum period, in which the mother-infant dyad remain in the hospital following birth (Nelson et al., 2016).
In-hospital infant formula supplementation has been associated with decreased breastfeeding duration at 2 months (Chantry et al., 2014), up to the first year of life (McCoy & Heggie, 2020). Brief episodes of in-hospital infant formula supplementation among breastfed newborns are associated with changes to the microbiota, and nonexclusive breastfeeding is associated with increased risks for allergic disease and type 1 diabetes (Eidelman, 2012;Forbes et al., 2018). Infant formula supplementation during this time can interfere with the supply and demand nature of this phase of lactogenesis (Pang & Hartmann, 2007) and can potentially lead to decreased supply and reduced breastfeeding duration, which is associated with adverse health impacts for the infant and mother (Feltner et al., 2018;Victora et al., 2016).
Infant formula supplementation of breastfed infants is necessary in some circumstances, after proper assessment identifies a medical indication, and when mothers' expressed milk or donor human milk are not available. The Academy of Breastfeeding Medicine (ABM) Clinical Protocol lists possible medical indications for supplementation such as hypoglycemia for the infant or chemotherapy treatment for the mother (Kellams et al., 2017). However, non-medically indicated factors have been found to be associated with unnecessary in-hospital infant formula supplementation such as caesarean section birth and large-forgestational age newborns (Garrison & Maisano, 2019). Lactation management-related factors have been previously reported as common reasons for in-hospital infant formula supplementation such as perceived insufficient milk supply, signs of inadequate intake and poor latch (Chantry et al., 2014). Personalised lactation care may minimise infant formula supplementation for these nonmedically indicated factors (Garrison & Maisano, 2019;Kellams et al., 2017;Medina Poeliniz et al., 2020
• Underlying many of the reported three most common reasons for infant formula supplementation is potentially lack of lactation management support that considers the social influences (e.g. from family and friends) and that is culturally relevant.
• These findings suggest that a variety of factors should be considered to address unnecessary infant formula supplementation.
(Centers for Disease Control and Prevention, 2020b

| Analysis
The responses to the open-ended question were analyzed using thematic analysis. We used the phases described by Braun and Clarke (2006), which include becoming familiar with the data (noting initial ideas), generating initial codes (systematically coding features of the data), searching for themes (gathering data relevant to the themes), reviewing themes (checking themes in relationship to the coded extracts), defining and naming themes (refining specifics of each theme) and producing a report (relating information back to the research question and literature) (Braun & Clarke, 2006). There were modifications to this process to accommodate our data set, considering the large volume of responses such as taking a simple random sample (SRS), developing a codebook and memo writing (Bazeley, 2013;Hennink et al., 2015). In addition, this process enabled the use of existing literature while also allowing flexibility to capture novel responses (Braun & Clarke, 2006).
To become familiar with the responses and to develop codes considering the large number of responses, a simple random sample (SRS) of 20% (n = 409) of the responses to the qualitative mPINC question were taken using SAS 9.4 and imported to MAXQDA2020 to begin qualitative analysis. For this 20% SRS, the first author (LB) and an additional qualitative analyst (DE) reviewed the data while noting initial concepts; developed codes and a codebook; and independently applied codes. LB and DE discussed coding discrepancies, overarching categories for codes and potential themes. LB wrote memos on the resolution to the discrepancies; LB updated the codebook; and LB and DE made corrections to previously coded data. LB coded the remaining 80% of the responses using the updated codes; themes were further reviewed and defined using memo writing while also considering ABM Clinical Protocols (Hernandez-Aguilar et al., 2018;Holmes et al., 2013;Kellams et al., 2017). Breastfeeding contraindications (e.g., illicit drug use, incompatible medication and HIV), higher level of care for infants, prematurity, offering donor human milk for supplementation instead of infant formula, and other extenuating circumstances were not included in further analysis due to the focus on infant formula supplementation of healthy, term, breastfed newborns. We wrote a report of our qualitative analysis, which included a description of our themes.
The results from the qualitative analysis were imported to SAS 9.4. Descriptive analysis was conducted to report the characteristics of the hospitals that responded to the mPINC survey. Descriptive analysis was also conducted to report the count and frequency of the themes and subcategories within the overarching themes. Some hospitals reported multiple subcategories from one theme; however, the descriptive statistics for themes only counted hospitals once if the theme was present.
For example, a hospital may list hypoglycemia, jaundice, and inadequate elimination as the three most common reasons for infant formula supplementation; however, this hospital would only be counted once in the frequency for the overarching theme of medical indications.

| RESULTS
Two thousand forty-five hospitals representing 70% of hospitals providing maternity care in the US responded to the question asking for the three most common reasons for infant formula supplementation in the 2018 mPINC survey. Hospitals were mostly non-profit (77%) and teaching hospitals (69%) and 25% were Baby-Friendly Hospital Initiative (BFHI) designated (Table 1)   and mothers' lack of confidence (0.3%).
Lactation management-related issues were reported by 51.3% of all hospitals. The most frequently mentioned subcategory for this theme was perceived low milk supply by the mother (16.5%), which encompassed mothers mentioning that they have 'no milk', and mothers mentioning not having 'enough milk' to provide to the infant. Many hospitals that reported perceived low milk supply also reported concerns about infant hunger (14.0%) as a separate common reason. The subcategory, concern about infant hunger, in contrast to perceived low milk supply included infants not 'getting enough' and additionally included the infant not appearing satisfied after feeding, which was expressed through infant crying. A variety of other concepts were mentioned related to lactation management including latching issues (10.0%); inconsolable infants (6.1%); cluster feeding (closely spaced nursing sessions) or feeding frequency (4.5%); difficulty breastfeeding (4.9%); breastfeeding concerns that arise during night hours (3.7%); lack of knowledge (3.2%) and soreness or discomfort of the breast or nipple (2.6%). The subcategory pain specific to breastfeeding (2.4%) consisted of responses that listed 'pain' due to concerns such as 'nipple damage' or 'cracked nipples'. In contrast, the subcategory soreness or discomfort of the breast or nipple (2.6%) included less severe breast and nipple-related issues.
A total of 36.1% of hospitals reported at least one of the most common situations leading to infant formula supplementation being physical but non-medically indicated. A previously conducted analysis using 2013 mPINC data among US maternity hospitals, reported that the average hospital reported 65% of infants were supplemented with infant formula due to maternal request (Nelson et al., 2016). A qualitative study conducted among low-income women found that maternal request for inhospital infant formula supplementation of healthy, breastfed infants was due to lack of preparation related to anticipatory guidance about infant behaviour (DaMota et al., 2012). Our analysis found that hospitals report that maternal requests are sometimes made after patient education is provided in the hospital setting, suggesting the need for more education before admission to the hospital for birth.
The most common lactation management concern reported was mothers' perceived low milk supply, which has been frequently reported by other studies (Boban & Zakarija-Grković, 2016;Pierro et al., 2016). In the early days following birth, low milk supply may be related to three potential factors, including (1) medical conditions that result in a delay in lactogenesis II, (2) practices that interrupt the normal physiology of breastfeeding and (3) mothers not understanding normal infant behaviour (Gatti, 2008;Kalmakoff et al., 2018;Nommsen-Rivers et al., 2012). Though research about primary insufficient breast milk supply related to concerns of the breast tissue is lacking, one older study suggests that it is rare, and is often secondary to practices that interrupt the normal physiology of breastfeeding (Neifert et al., 1990). The prevalence of pre-pregnancy obesity and older age at first birth are increasing nationally, and these factors may impact the onset of lactogenesis II, in which copious milk secretion occurs (Driscoll & Gregory, 2020;Mathews & Hamilton, 2016;Nommsen-Rivers et al., 2012). More research is needed to determine if low milk supply during the first few days following birth is primary (directly related to the physiology) or secondary (related to practices that interrupt the normal physiology of lactation). Practices such as skin-to-skin have been found to reduce the risk of infant formula supplementation among breastfed newborns, and this is a potential intervention to facilitate lactogenesis II and reduce infant formula supplementation (Kalmakoff et al., 2018;World Health Organization and UNICEF, 2018). Mothers' perceived low milk supply has been found to be related to perceived hunger of the child, which is expressed by crying and number or frequency of feedings (Gatti, 2008). Professional support that guides mothers to early optimal latching and informs signs of efficacious infant suckling may help to reduce mothers' perceived low milk supply and other related factors that potentially lead to infant formula supplementation (Galipeau et al., 2017;Gatti, 2008). In addition, some hospitals reported that many of the lactation management-related issues arise during the Note: Theme subcategories do not total to 100% because hospitals were counted once for frequency of themes and were counted more than once if applicable for each subcategory. (e.g., a hospital may list hypoglycemia, jaundice and inadequate elimination as the most common reasons for infant formula supplementation; however, this hospital would be counted once in the frequency for the overarching theme of medical indications).
Abbreviations: ABM, Academy of Breastfeeding Medicine; mPINC, Maternity Practices in Infant Nutrition and Care survey.
| 7 of 11 night hours. One study reported that infants born at night had double the odds of in-hospital infant formula supplementation compared to infants born during the day (Grassley et al., 2014). There have also been reported differences in night staff attitudes compared to day staff attitudes, in which night staff are reported to be less committed to providing breastfeeding support because of the perception that the benefits of providing rest for the mother outweigh the benefits of providing breastfeeding support (Nickel et al., 2013;Schmied et al., 2011). Lactation management support during the night hours may be an important support for breastfeeding mother-infant dyads (Nickel et al., 2013;Schmied et al., 2011).
Similar to other studies, we found that physical conditions such as exhaustion and mothers' desire for sleep were one of the three most common reasons for infant formula supplementation (Pierro et al., 2016). Although infant formula feeding enables others, including family and medical staff, to feed the infant while the mother rests, the potential consequence includes disrupting the normal physiology of lactation resulting in a decreased milk supply, shorter duration of breastfeeding and adverse consequences of exposure to infant formula (e.g., changes to the microbiota, increased risk of allergic disease, etc.) (Chantry et al., 2014;Eidelman, 2012;Forbes et al., 2018;McCoy & Heggie, 2020). Other physical conditions have been reported, in which infants born via caesarean section and largefor-gestational-age infants were at greater risk for non-medically indicated infant formula supplementation (Garrison & Maisano, 2019). Identifying mothers with these physical but non-medically indicated conditions and targeting breastfeeding support may enable lactation staff to promptly intervene to avoid unnecessary infant formula supplementation (Garrison & Maisano, 2019).
The role of social influences on infant formula supplementation and nonexclusive breastfeeding has been reported previously in qualitative literature which suggests that this may be due to limited family experience and limited family breastfeeding knowledge (Asiodu et al., 2017;Deubel et al., 2019). Another study found that fathers' preference for infant formula supplementation was significantly associated with in-hospital infant formula supplementation (Parry et al., 2013). Similarly, many hospitals in our analysis used the term 'parents', which suggests that mothers were not alone in their decision making, and that fathers or partners may also have a role in the decision-making process for in-hospital infant formula supplementation. Further work is needed to understand the influence of partners and the potential joint decisions made between mothers and partners. It is possible that in some cases that when hospitals referred to 'parents' decision' that they meant mothers rather than fathers or other partners. The language surrounding female reproduction may have been desexed to account for people who are giving birth but who, because of their gender identity, do not wish to be referred to as mothers' (Grasso et al., 2021). The use of desexed terms are important for providing individual care, and more sophisticated methods for collecting information related to social influences as a common reason for infant formula supplementation reported by hospital staff may be needed to make this distinction in medical records and research (Grasso et al., 2021).
In alignment with other studies, perceived culture was also found to influence in-hospital infant feeding decisions (Asiodu et al., 2017;Hawley et al., 2015;Hohl et al., 2016;Pierro et al., 2016). Bias and stereotyping in healthcare may influence medical staff perceptions and behaviour toward patients of specific backgrounds (FitzGerald & Hurst, 2017). There are some common racial and ethnically driven misconceptions and stereotyping in breastfeeding practices, such as 'Hispanics do las dos cosas (both infant formula feeding and breastfeeding)' or 'black women do not breastfeed' (Panchula, 2012).
Although this may be true in some cases, it is crucial not to generalise any behaviour for all mother-infant dyads of the same racial/ethnic group as this may negatively impact patient care (Hughes et al., 2020). A potential solution to dispelling myths includes maternity care staff training that focuses on the cultural humility approach, which is a lifelong commitment to building awareness about their own cultural biases and truly learning about patients as unique individuals with their own personal cultural background (Hughes et al., 2020;Tervalon & Murray-García, 1998). In addition, qualitative studies report that cultural differences may be related to factors such as lack of support networks that normalise breastfeeding among African American women and pressure to adopt the behaviours of US culture among Hispanic mothers (Deubel et al., 2019;Wambach et al., 2016).
Hispanic mothers who immigrate to the US are reported to continue the cultural traditions of their native countries of initiating breastfeeding (Cartagena et al., 2014). However, they are reported to supplement with infant formula due to cultural practices of providing prelacteal feedings because of the concern that colostrum lacks nutritional value (Pak-Gorstein et al., 2009). Hispanic mothers are also reported to supplement breastfeeding with infant formula due to the misperception that infant formula provides additional nutrients, without understanding the risks of infant formula supplementation (Bunik et al., 2006). Peer breastfeeding support may be useful in overcoming cultural barriers and may facilitate delivery of culturally relevant support in hospitals with limited access to trained lactation professionals (Chapman & Pérez-Escamilla, 2012;Lutenbacher et al., 2018).
In contrast to previously conducted studies, we found that rea-

| CONCLUSION
Lactation management support underlies many of the most common reasons hospitals provide for giving infant formula to healthy, term breastfed newborns. Timely and culturally sensitive lactation management support that is targeted to mother-infant dyads with potential medical indications and physical but non-medically indicated conditions could potentially reduce unnecessary in-hospital infant formula supplementation.