Key points

Introduction

Human milk (HM) feedings from the infant’s own mother reduce the risk of numerous short-term and long-term morbidities, their associated sequelae, and costs of care for premature and other at-risk infants. For premature infants, higher doses of HM are associated with a lower risk of enteral feeding intolerance, late-onset sepsis, necrotizing enterocolitis, chronic lung disease, retinopathy of prematurity, neurocognitive delay, and rehospitalization at 18 and 30 months of age. Further, the postnatal timing of high doses of HM may be important, because several studies suggest that high doses of HM during the first 14 to 28 days of life are associated with lower risk of various adverse outcomes in the neonatal intensive care unit (NICU). A separate line of research also suggests that the presence of bovine products (not merely the absence of HM feedings) negatively affects intestinal permeability and gut colonization, making the relationship between HM feedings and morbidities even more complex. However, the rapidly accumulating evidence suggests that the bioactive components of HM provide morbidity-specific protection via different mechanisms during different exposure periods in the NICU hospitalization.

Although these outcomes of HM feedings are well documented for infants in the NICU, families and health care providers struggle to translate this evidence into actionable policies, procedures, guidelines, and resource allocation to improve the use of HM in the NICU. This article summarizes the processes for creating a culture of evidence for increasing the dose and exposure period of HM feedings in the NICU, including the implementation of evidence-based quality indicators for measuring and benchmarking HM use. Best NICU practices for encouraging mothers to initiate and maintain lactation, protecting the maternal milk supply, caring for pumped HM, transferring from gavage to at-breast feeding, and using lactation technologies to solve common NICU problems with HM feedings are summarized.

Introduction

Human milk (HM) feedings from the infant’s own mother reduce the risk of numerous short-term and long-term morbidities, their associated sequelae, and costs of care for premature and other at-risk infants. For premature infants, higher doses of HM are associated with a lower risk of enteral feeding intolerance, late-onset sepsis, necrotizing enterocolitis, chronic lung disease, retinopathy of prematurity, neurocognitive delay, and rehospitalization at 18 and 30 months of age. Further, the postnatal timing of high doses of HM may be important, because several studies suggest that high doses of HM during the first 14 to 28 days of life are associated with lower risk of various adverse outcomes in the neonatal intensive care unit (NICU). A separate line of research also suggests that the presence of bovine products (not merely the absence of HM feedings) negatively affects intestinal permeability and gut colonization, making the relationship between HM feedings and morbidities even more complex. However, the rapidly accumulating evidence suggests that the bioactive components of HM provide morbidity-specific protection via different mechanisms during different exposure periods in the NICU hospitalization.

Although these outcomes of HM feedings are well documented for infants in the NICU, families and health care providers struggle to translate this evidence into actionable policies, procedures, guidelines, and resource allocation to improve the use of HM in the NICU. This article summarizes the processes for creating a culture of evidence for increasing the dose and exposure period of HM feedings in the NICU, including the implementation of evidence-based quality indicators for measuring and benchmarking HM use. Best NICU practices for encouraging mothers to initiate and maintain lactation, protecting the maternal milk supply, caring for pumped HM, transferring from gavage to at-breast feeding, and using lactation technologies to solve common NICU problems with HM feedings are summarized.

A culture of using the evidence about HM in the NICU

The Rush Mothers’ Milk Club is an evidence-based lactation program in the 57-bed NICU at Rush University in Chicago, in which 98% of mothers provide milk for their infants in the NICU, and the average daily dose of HM received during the NICU hospitalization by very low birth weight (VLBW; <1500 g birth weight) infants exceeds 60 mL/kg/d. This program translates the evidence about HM into understandable concepts and teaching materials for health care providers and families, and allocates resources, such as industrial freezers to store HM and the use of breastfeeding peer counselors (BPCs), to optimize the dose and exposure period of HM feedings for all infants in the NICU. Most fundamentally, the Rush program has established a culture of using the evidence, which has in turn led to high rates of HM feeding.

Of the various therapies used routinely in the NICU, HM use has among the most empiric support for safety, efficacy, availability and cost-effectiveness. When conceptualized within a culture of using the evidence, HM feedings are a therapeutic priority for compromised infants, implemented in a manner like other evidence-based practices that improve outcomes in the NICU. Specifically, this process entails engaged practitioners who knowledgeably discuss the evidence for use of HM in the NICU, policies and guidelines that translate the evidence into routine clinical practices, and quality improvement efforts that provide feedback about the achievement of evidence-based benchmarks. In the context of a culture of using the evidence, infrastructure or resource needs are addressed for HM feedings (eg, storage freezers and waterless milk warmers) and considered in the same manner as other evidence-based interventions known to improve neonatal health outcomes.

In contrast, we do not advocate conceptualizing the NICU as having a culture of breastfeeding, which may lead to use of non-evidenced strategies based on emotional or sociopolitical rationale and avoidance of lactation technologies (eg, creamatocrits, test weights, nipple shields, and special bottle units for feeding HM), making breastfeeding unnatural. The culture of using the evidence regarding breastfeeding is not based on changing staff attitudes and beliefs, does not accept staff indicating that they cannot help a mother feed her infant at the breast because they have not breastfed themselves, but is based on consistent dissemination of evidence that provides the highest standards of care for staff and families.

Evidence-based quality indicators for the use of HM in the NICU

A first step in translating the evidence about HM feedings in the NICU is to establish evidence-based quality indicators against which practice improvements can be benchmarked. Currently used quality indicators do not reflect the research that demonstrates the relationship between the dose and exposure period of HM feedings and the reduction in the risk of morbidities for infants in the NICU. Current indicators measure only the proportion of infants in the NICU who ever received HM and the proportion who were still receiving any HM at the time of NICU discharge, which does not adequately reflect the evidence about risk reduction. For example, the following 2 clinical scenarios both result in classification of an extremely low-birth-weight infant as receiving any HM in the NICU and no HM at discharge: (1) received exclusive HM feedings for 60 days followed by exclusive formula in the final week before NICU discharge, versus (2) received a single HM feeding while in NICU hospitalization. Simple-to use quality indicators that measure the amount and timing of HM feedings received by the infant in the NICU are needed in order to make the quality indicators consistent with the research.

The relationship between HM feeding status at the time of NICU discharge was recently explored as a part of an ongoing National Institutes of Health (NIH) cohort study in the Rush NICU that enrolled 400 VLBW infants between 2008 and 2012. Of the 295 VLBW infants for whom data had been analyzed at the time of this writing, 289 (98%) infants received some HM. The average daily dose of HM received during the NICU hospitalization was 60 mL/kg/d (range, 0–156), and total HM intake received during the first 28 days after birth was 51 mL/kg/d (range, 0–135) or 71% (0%–100%) of total enteral feeding volume. Of the infants who were discharged receiving no HM (62% of the cohort), we found that exclusive HM feedings were received for 24% of the NICU hospital days, and partial HM feedings were received for 38% of the NICU hospital days. HM feedings constituted 76% and 58% of total enteral feedings during the first 14 and 28 postnatal days, respectively, for infants in the group who received no HM at discharge. Given that studies have shown a beneficial impact of high doses of HM feedings during the first 14 or 28 days after birth in premature infants, we propose that evidence-based quality improvement measures incorporate these exposure periods ( Box 1 ).

Best practices for sharing evidence about HM with families of babies in the NICU

A major barrier to the initiation and maintenance of lactation in mothers whose infants are in the NICU is the inconsistent information that they receive regarding the importance of HM for their infants, strategies to pump and store their expressed milk, specific guidelines for transferring the infants to feeding at the breast, and combining pumping and feeding during the late NICU hospitalization and after discharge. When HM is used within a culture of evidence, addressing these issues becomes an NICU responsibility, not the job of a single lactation practitioner. Policies, procedures, and talking points that translate key HM research into understandable words and concepts are developed and implemented so that messaging and information are consistent for staff and families.

Consistency of information

In the Rush Mothers’ Milk Club, families receive standardized information about the importance of HM from perinatologists, neonatologists, nurses, nurse practitioners, NICU dietitians, and NICU-based BPCs before an infant’s birth and throughout the NICU hospitalization. One consistent message is, “Your milk is a medicine that helps protect your baby from health problems and complications during and after the NICU hospitalization.” Other talking points are summarized in Box 2 . With this strong message, 98% of mothers of infants in the NICU provide their milk although 50% of these women originally intended to feed formula. These mothers changed the decision to provide HM after the initial consultation with the neonatologist. Several studies have shown that this matter-of-fact messaging does not make mothers feel coerced, pressured, or guilty, and that the women indicate that they depend on NICU care providers to share this evidence with them. Further, in all of these studies, low-income African American mothers were disproportionately represented among the women who had initially chosen formula for their infants, but changed the decision to provide HM when the neonatologist indicated the advantages of HM for their own infant. The need for specific education of families at risk for premature birth, but unlikely to provide HM, resulted in the production of an educational DVD ( In Your Hands , Rush Mothers’ Milk Club, Chicago, IL) featuring families who detailed changing the decision to provide milk for their own infants and the beneficial outcomes that they noted. This DVD is played in the hospital educational television channel for all families of new infants in the NICU.

Parents of infants who were in the NICU provide direct lactation care for new families

Once mothers of infants in the NICU have made the decision to initiate lactation for their infants, lactation care must be consistent, individualized, and highly specialized to address the lactation challenges of breast pump-dependent mothers with fragile infants. In 2005, the Rush Mothers’ Milk Club implemented a program wherein parents of infants formerly cared for in the Rush NICU were hired as BPCs. These parents completed a 5-day training program in generic BPC practice and upon their employment at Rush, also completed a 12-week orientation that included NICU-specific evidence and practices. Contrary to other models of BPC practice, these former parents of infants in the NICU work as an integral part of the health care team, assuming many lactation interventions traditionally performed by lactation consultants, with the bedside nurse serving as their major resource. The BPCs also work as research assistants on the externally funded research projects of the program, manage the NICU milk storage procedures and make home visits after infants in the NICU are discharged from the hospital.

BPCs are available in the Rush NICU 7 days a week, morning to evening, and form peer relationships with new families because of the shared experience of providing HM for an infant in the NICU. The BPCs conduct an initial visit with all mothers of infants in the NICU in the antepartum, intrapartum, or postpartum units, at which time they share the story of their own infants in the NICU and explain the importance of providing HM. The BPCs do all of the initial teaching about pumping, collecting, storing, and labeling HM, and sit with the mother when she uses the breast pump for the first time, adjusting the pump suction pressure and fitting breast shields. The BPCs help mothers solve problems such as low milk volume, sore nipples, lack of family support, and making pumping a priority despite the stress of having an infant in the NICU. Two published studies have detailed the mothers’ and the health care providers’ experiences with the BPCs in the Rush NICU. The mothers reported that they preferred to receive lactation care from the BPCs, whom they perceived as knowledgeable, empathetic, and inspirational. The health care providers reported that the BPCs were a valuable part of the NICU health care team, who made their work easier and more satisfying.

Families learn the science of HM, lactation, and breastfeeding

Central to the Rush Mothers’ Milk Club program is the use of evidence to answer families’ questions and address their concerns about HM, lactation, and breastfeeding. To ensure staff consistency and competency with respect to these topics, the program has developed policies, procedure, talking points, and professionally produced products (eg, brochures and parent education sheets) for families that summarize common concerns. These products constitute an NICU toolkit for translating the evidence about HM into actionable practices, ensuring that information is shared accurately and consistently.

The Rush Mothers’ Milk Club luncheon meeting also provides a forum for group lactation care in which families learn scientific principles about HM and lactation, and can share their own concerns and experiences. The discussion is facilitated by staff and attended by the BPCs, current families, and parents whose infants were in the NICU who return to share their stories and seek additional information about providing HM via pumping or feeding at the breast. Although the group provides new families with much-needed support, the focus remains on sharing relevant scientific information, such as why a mother in the group might be at risk for delayed onset of lactation. Initiating lactation and maintaining an adequate milk supply despite the many obstacles to doing so are topics that always emerge, and the experienced mothers in the group share strategies with the newer mothers.

Protecting maternal milk supply in pump-dependent mothers with infants in the NICU

Most mothers who provide HM for their infants in the NICU are breast pump-dependent, meaning that they rely on the breast pump instead of a healthy breastfeeding infant for the initiation and maintenance of lactation. Breast pump-dependency, in combination with a myriad of factors that predispose to delayed onset of lactation and low milk volume, make mothers of infants in the NICU at greater risk for insufficient milk when compared with mothers with healthy breastfeeding infants. Because milk is medicine for infants in the NICU, the single most important priority in the NICU is to protect the maternal milk supply by applying knowledge of the physiology of lactation to the individual mother’s goals for providing her milk. This process is facilitated by the use of milk volume targets, milk diaries, easy-to-use assessment tools, and evidence-based milk expression protocols. Breast pumps, pumping kits, breast shields, and other supplies should be chosen based on their proven effectiveness, efficiency, and comfort in mothers of infants in the NICU.

Physiology of lactation applied to the pump-dependent mother of an infant in the NICU

In all mammals, the trigger for secretory activation (lactogenesis II) is the withdrawal of progesterone that occurs with the birth of the placenta, thus removing its inhibitory effect on serum prolactin. Colostrum, the initial milk product, is the transition from intrauterine to extrauterine nutrition for the infant, and is rich in bioactive factors that grow, mature, and protect the immature intestinal tract of the infant. A healthy term breastfeeding infant removes approximately 15 mL of colostrum in 10 breastfeedings during the first 24 hours after birth and does so using a uniquely human infant sucking pattern characterized by a rapid rate, relatively strong sucking pressures, and intermittent pauses. This early suckling on the part of the human infant is believed to provide a type of stimulus or programming during a critical window after birth that protects the maternal milk supply throughout lactation. Under the ideal conditions of unrestricted breastfeeds, the mother’s milk output increases from 15 mL during the first day of life to 500 to 600 mL of milk by days 4 to 7. The challenge in the NICU is to apply this physiology to the breast pump-dependent mother, for whom the early postbirth period is complicated by stress and anxiety about her fragile infant and her own medical and birth complications.

Milk volume targets

Although several lines of evidence suggest that the very early postbirth period is a critical time for the stimulation or programming of subsequent milk yield, mothers of infants in the NICU seldom receive this clear information in words that they can act on. For many mothers and care providers, an adequate maternal milk supply means that there is enough HM for the infant’s daily feedings. Mothers have heard that as their infants require more milk, they will make more milk, and health care providers are concerned about pressuring mothers about milk supply during this vulnerable time. However, research indicates that milk output during the first 2 postnatal weeks predicts the adequacy of milk volume during the late NICU hospitalization. Thus, it is of primary importance that mothers understand from the beginning that there are 2 milk volume targets, which are enough for: (1) their infant in the NICU at the time, which may be very small amounts because of prematurity, surgical complications, or fluid restrictions; and (2) protecting the milk supply by early programming that enables their infants to receive exclusive HM feedings after the NICU hospitalization. Protecting the milk supply translates into minimal milk volumes of 350 mL per day (adequate for a 2-kg infant at discharge), and volumes closer to 1000 mL per day ensure enough milk even if mothers experience later problems with their milk supply.