The benefits of feeding mother's own milk (MOM) to preterm and critically ill infants in the neonatal intensive care unit (NICU) for improved health are well established and include a decreased incidence of necrotizing enterocolitis, late-onset sepsis, retinopathy of prematurity, bronchopulmonary dysplasia, and neurodevelopmental delays.1–3 Earlier this year, the American Academy of Pediatrics released their updated policy on Breastfeeding and the use of Human Milk, which recommends exclusive breastfeeding for 6 months and continued breastfeeding for 2 years and beyond.4 However, for infants born preterm or critically ill, less than 20% receive any MOM at 6 months and this limited exposure is most often due to insufficient milk production by their mothers.5,6 Furthermore, significant racial disparities exist regarding preterm birth, provision of MOM, and health outcomes. Black women have a 2.6× greater risk of delivering a preterm infant than White, non-Hispanic women, are 7.6× less likely to provide MOM to their infant, and their infants are at highest risk of complications, which may be mitigated by consumption of MOM.7–9

Since the 2012 American Academy of Pediatrics recommendation that preterm infants be fed donor human milk (DHM) when MOM is unavailable, the use of DHM has become standard care in most NICUs.10,11 Although DHM and MOM are often considered interchangeable, evidence clearly supports the superiority of MOM in terms of protection against prematurity-related complications.12,13 Pasteurization of DHM reduces and/or eliminates many of the protective elements, including immunoglobulins, cytokines, and growth factors, as well as destroys the commensal microbiota.14,15 Furthermore, due to diminished protein content and decreased fat absorption from inactivation of bile salt-stimulating lipase by pasteurization, infants fed DHM are at risk for suboptimal growth.16,17 Finally, some studies suggest that the availability of DHM in NICUs may reduce MOM consumption in preterm infants.18 Thus, our focus should clearly be on increasing the amount of MOM consumed by infants in the NICU and this requires a systematic, multidisciplinary approach beginning antenatally and including both maternal and neonatal services.

It is well known that milk production in the first days postpartum is closely associated with the amount produced at 6 weeks and infants whose mother comes to volume (production of at least 500 mL of MOM by day 14 postpartum) are 11× more likely to be receiving MOM at NICU discharge.19 Thus, strategies to increase MOM production must begin immediately after delivery and focus on the first 14 days postpartum including initiation of expression soon after delivery and frequent MOM expression using an appropriate breast pump.

Initiation of milk expression should begin as soon as possible following delivery and no later than 6 hours postpartum.20 However, mothers delivering critically ill and/or preterm infants, often have underlying comorbidities and deliver via cesarean section making maternal self-initiated expression difficult. Because mothers often require extensive support to express, initiation is often delayed due to insufficient time and available staff.21 To facilitate timely expression initiation, it is possible that following a brief education session, the mother's support person could provide expression assistance.22 Because mothers delivering infants requiring NICU admission are often hospitalized for days prior to delivery, this education could take place antenatally.

However, beginning expression soon after delivery is not sufficient to establish a mother's milk supply. Frequent expression during the initial few days following delivery and through the first 14 days postpartum is also essential.19,23 Unfortunately, due to perceived maternal acuity and exhaustion, nursing time constraints, and lack of information regarding the importance of early frequent expression, mothers often express much less frequently than required to initiate lactation. The first 3 to 5 days are a critical window during which decreased expression frequency is associated with decreased long-term milk volume.19 It is necessary that both mothers and staff understand the potential negative effects of missed expression sessions on both short- and long-term milk production and make informed decisions based on this information. It is also possible that an appropriately trained support person could provide expression assistance as needed until the mothers have sufficiently recovered to independently express.

Finally, it is imperative that mothers have access to hospital-grade breast pumps beginning with one being available in her recovery and postpartum room to avoid delays or interruptions in expression. Unfortunately, mothers are often discharged home before obtaining an appropriate pump for home use and are thus dependent upon hand pumps or battery-operated breasts pumps. These types of pumps are inadequate for providing the necessary breast stimulation and milk removal needed to promote adequate lactation in the early days postpartum. It is therefore necessary that systems are developed to provide mothers of infants in the NICU with hospital-grade breast pumps prior to their discharge home.

Nurses are uniquely positioned to lead and facilitate lactation support programs, which optimize lactation success consistent with a mother's stated goals. It is essential that nurses who care for infants admitted to the NICU and/or their mothers create and support an environment conducive to lactation and utilize evidence-based strategies to optimize milk production in mothers of critically ill and preterm infants. These efforts are necessary to facilitate increased MOM production, reduce the need for DHM, and increase the likelihood that sufficient quantities of MOM are available for infant consumption thus improving health outcomes of vulnerable infants in the NICU.

—Leslie A. Parker, PhD, APRN, FAAN
University of Florida, College of Nursing,
Gainesville, Florida.

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