Vol. 18 Issue 33
Comprehensive study on breast milk
Breast milk is known to boost brain development, prevent life-threatening infections, decrease allergies, and promote stronger bones and a higher IQ. However, premature infants that weigh only ounces may be unable to swallow the milk.
To address this issue, researchers at the University of California (UC) San Diego Medical Center have launched a comprehensive program to study how breast milk can be fed to preemies and to identify the ingredients that give human milk its life-boosting qualities. Supporting Premature Infant Nutrition (SPIN) is focused on the provision, analysis and research of human milk to improve nutritional and neurodevelopmental outcomes in preterm babies. The new program is believed to be the first of its kind in the United States.
"UC San Diego Medical Center is a 'Baby Friendly Hospital,' which means we encourage breastfeeding as the preferred method of infant nutrition for our newborns," said Neil Finer, MD, director of neonatology. The medical center became accredited as a "Baby Friendly Hospital" in 2006, one of a handful of academic hospitals to achieve this recognition.
"We are now applying this same model of care to our smallest, most vulnerable infants," explained Dr. Finer, who oversees the recently expanded 49-bed regional neonatal intensive care unit (NICU) in Hillcrest. "The goal is a better understanding of human milk to achieve healthier preemies who are breastfeeding when they leave our hospital."
SPIN is a multifaceted study to examine the chemistry of breast milk, how to best handle and preserve the milk, and how to offer maternal support for milk production in the NICU. The UC San Diego Medical Center labor and delivery service, which specializes in high-risk pregnancies, and its NICU are nationally recognized centers of excellence for maternity and newborn care. Team members in the SPIN program include neonatologists, gastroenterologists, intensive care nurses, and lactation and nutritional experts.
"Babies born prematurely are in a nutritional crisis," said Jae Kim, MD, PhD, a neonatologist and gastroenterologist at the medical center. "The baby is in a doubly difficult situation of dealing with life outside the womb while having a highly immature gastrointestinal system. This can lead to major bowel dysfunction or failure. While this is a critical time to care for the infant, it is also a pivotal time to help mom make breastfeeding a priority for the long-term health of the child."
"Breast milk can save infants' lives," said pediatrician Lisa Stellwagon, MD, director of SPIN. "While premature infants may not be capable of breastfeeding in the short term, we are identifying strategies and techniques to provide the infants the milk and to make the milk available in the long run. The data collected from this study will be shared globally with hospitals that would like to adopt similar programs for premature infants."
The NICU is a complex medical environment where the priority is on saving the lives of premature, sometimes critically ill infants. While the focus is on emergency respiratory, pulmonary and nutritional interventions, the act of breastfeeding may be ignored or overlooked.
The SPIN program has established a supportive environment where mothers are encouraged to pump milk around the clock. Frequent pumping keeps up the milk supply until the preemie achieves a coordinated sucking and swallowing reflex. Mothers pump their milk every two hours. The program provides support through ergonomic assessments of feeding positions, educational flashcards with breastfeeding tips, emotional and nutritional support, and education for fathers or life partners.
Pumped milk is labeled with the family name and an identification number and scanned into a database. The SPIN program is using a special near-infrared analyzer, which is traditionally used in the dairy industry to determine the nutritional content of cow's milk, to develop quick, simple methods for measuring the nutritional content of human milk.
The analyzer in the NICU at UC San Diego has been calibrated for human milk. Daily milk samples are analyzed for nutritional values such as calories, fat, protein and lactose to help the medical team determine the ideal amount of nutrient supplementation to add to mother's milk.
"Human breast milk is full of carbohydrates, lipids, vitamins and minerals," said Dr. Kim. "There are approximately 300 components to breast milk, including small, biologically active compounds that aid in the formation of the gastrointestinal tract. The contents vary dramatically from mother to mother and feeding to feeding depending on the baby's needs."
After identifying the contents of the milk, the SPIN team will evaluate the best way to feed the baby. The team is testing different aspects of manual feeding, such as the optimal size of the syringe and temperature of the milk. Once its exact chemistry is known, the milk can be fortified accurately to aid child growth. Currently, both cow- and human-based milk fortifiers are used as supplementation.
"We plan to look for correlations between the mother's diet and the nutritional characteristics of the breast milk," said Dr. Stellwagon. "We may be able to identify certain foods and supplements that aid in the infant's growth and development."
Infants born prematurely sometimes develop an infection called necrotizing enercolitis (NEC), the most common life-threatening gastrointestinal emergency in the newborn period. NEC causes intense inflammation and acute intestinal necrosis or death. Approximately 7 percent of the smallest preemies develop this infection, and it is fatal in one-third of cases. NEC compromises 1 percent to 5 percent of all NICU admissions and affects 10 percent of infants born at less than 3 pounds.
"Fortunately, breast milk contains enzymes that help protect against NEC," said Dr. Kim. "Babies born at 1 pound have their intestinal development in place, but all things attributed to function are either at the earliest phase or have not kicked in at all. Breast milk has growth factors that affect the ability of the gut to grow and can get the digestion process on track to prevent this dangerous infection."
"Every second counts for the growth rate of infants, especially in the first days when babies are gaining up to 20 grams per kilogram of weight per day," Dr. Kim said. "The brain increases 5 percent in size every 48 to 72 hours. Adequate and extra nutrients can improve brain growth, which is something the SPIN program is measuring."
The SPIN team calculates brain development of the infants by measuring the circumference of their head or performing magnetic resonance imaging (MRI) exams. The infants will receive developmental testing during follow-up visits to the NICU.
"Human milk provides benefits that are both nutritional and neurological. In our lifetime we will not be able to replicate its biological complexities," said Dr. Stellwagon. "The best thing for all newborns is breast milk. The SPIN program will help us learn how and why for preemies."
In addition to Drs. Finer, Kim and Stellwagen, members of the SPIN team include Tom Moore, MD; Yvonne Vaucher, MD, MPH; Corey Anaka, MD, RN; Laurel Lee, RD; Donna Posin, MPA, OTR/L; Samme Fuchs, RN; Jan Hebert, RN; Terry Lawson, RN; Linda Levy, RN; Alison Wolf, RN; Amy Yates, RN; and Liz Zborowski.
The United States has one of the highest pre-term birth rates in the world, with 12 percent of babies being born before 37 weeks gestation, according to the Centers for Disease Control and Prevention. The March of Dimes reports that premature births have been escalating steadily over the past two decades.ÊIn 2005 more than 525,000 infants were born prematurely, the highest number ever reported in this country. The rate of premature birth increased almost 35 percent in the past quarter century, from 9.4 percent in 1981 to 12.7 percent in 2005. n
Jackie Carr is on staff at UC San Diego Medical Center.