Even When Feeding Breastmilk There Are No Free Lunches

The recommendation that mothers' own milk, appropriately fortified, should be the primary enteral diet for all very low-birth-weight infants (i.e., birth weight less than 1.5 kg) has been universally accepted as the standard of care. ¹ But as the old adage proclaims, “there are no free lunches.” The feeding of mothers' fresh breastmilk has undoubtedly led to a decrease in necrotizing enterocolitis (NEC), but at the possible trade-off of an increased incidence of acquired cytomegalovirus (CMV) infection. Older reports had discounted the clinical significance of these infections, as to both short-term morbidity/mortality and long-term neurodevelopmental outcome. However, recent publications have presented data that this may be a much more serious clinical problem than previously realized. Although over 80% of mothers can be documented to be seropositive for CMV prior to pregnancy, minimizing the risk of an intrautero-acquired CMV infection, an equal percentage of seropositive mothers will have reactivation of the virus postnatally and will excrete live CMV in their milk within a few weeks after delivery. Thus, feeding such raw fresh milk has the potential for causing an acquired CMV infection in the neonate.

To date, there are no reports of any clinical significance to an “infection” in term infants; however, increasing numbers of recent reports indicate that for the vulnerable high-risk preterm infant such an infection is not always benign. Significant serious sepsis-like syndrome, respiratory failure, and death in the short term have been documented,^2,3 and long-term neurodevelopmental abnormalities have been suggested. ⁴ This concern regarding the CMV infectivity of fresh human milk has led to increasing numbers of recommendations, particularly in Europe, that the high-risk preterm infant be fed only pasteurized milk, even mother's own milk. Such a recommendation has led to a concern that there might be a trade-off with this policy, with the downside being an increase in infective and inflammatory processes resulting from the heating decreasing both the cellular and humoral protective value of raw milk.

As such, the report of Stock et al. ⁵ in this issue of Breastfeeding Medicine documenting that pasteurization decreases the rate of acquired CMV infection at the possible “expense” of increasing the rate of NEC is both disturbing and challenging. Although the study was not a randomized prospective study and the increased NEC rate was not statistically significant, the results are of sufficient concern to challenge investigators to organize a proper large multi-institutional prospective study that can delineate more accurately what is the health cost–benefit ratio of routine pasteurization and to what degree of worth is the trade-off. At this point in time, North American neonatologists, as opposed to their European colleagues, have chosen to favor the feeding of unpasteurized fresh milk, but it is clear that more data are urgently needed to set proper clinical guidelines for how and what to fed these most vulnerable infants.

Pasteurization is also the subject of the article by Naicker et al. ⁶ This article highlights how a combination of low-cost technology (a pot of boiling water) and a smartphone “app” can facilitate the preparation of bacteria-free donor milk for high-risk newborns in resource-limited settings. The reality that smartphones, which in a seeming paradox are nearly ubiquitously available even in the most impoverished parts of the globe, can be a proper substitute for high-cost sophisticated equipment is detailed in this study. Beyond the specifics of the issue of bacterial contamination of human milk and the infectious disease implications of such, this study should serve as a stimulus for creative use of the new digital technology. We should understand that smartphones are essentially highly advanced hand-held computers with the capacity for interactive communication with the patient, caretakers, and the worldwide medical community, and as such they should be creatively integrated into our medical toolkit.

Only in recent years have neonatologists focused on the needs, clinical course, and long-term prognosis of infants born in what is now called the late preterm period (35–37 weeks of gestation). Although these infants usually do not suffer like the very low-birth-weight infant from life-threatening conditions, such as severe respiratory distress syndrome and intraventricular hemorrhage, it has become increasing clear that they are not just small term infants and that they do have increased morbidity and mortality compared with full-term infants. Among the myriad of clinical problems of the late preterm infant, feeding difficulties stand out as the most common, and thus the challenges of establishing a successful mother–infant feeding dyad are all too real. Thus, the information from the study of Kair et al., ⁷ which focuses on LATCH scores as a guide to managing these vulnerable infants, is important. Surely, such data will assist in proper postpartum care of the mother and infant and in realistic discharge timing and planning.

That breastfeeding has implications beyond the infant's well-being is a given, but discussions on its effect on maternal health usually are limited to issues of maternal weight gain, cardiovascular status, and breast and ovarian cancer risk. That breastfeeding, in addition, perpetuates a hypoestrogenemia state that manifests itself with excessive vaginal dryness and maternal mood changes is the subject of the study of Agarwal et al. ⁸ Such information will assist the clinician in providing anticipatory guidance to mothers as to what they should expect with breastfeeding and will guide in the practitioner in providing appropriate therapy for the effects of low estrogen levels in the breastfeeding woman.

All in all, this is a most interesting, balanced, and practical issue of Breastfeeding Medicine.