“Results suggested that an early supplementation with DHA to lactating mothers with low dietary DHA was successful in increasing DHA status in very preterm infants," said lead study author, Isabelle Marc, MD, PhD, an assistant professor in the Department of Pediatrics at Laval University in Quebec, Canada, and clinician researcher at Centre Hospitalier Universitaire de Québec.
Dr. Marc said she and her colleagues set out to uncover the possible link between the consumption of DHA and brain development for babies in general and preterms in particular. “DHA is a major component of brain cell structure,” she explained. “Intra-uterine accretion of DHA in tissues is absent in very preterm born with low reserves of fat. DHA milk concentration is low in Canadian women and very closed from their DHA consumption. So breastfed preterms are vulnerable to dietary deficiency since their growth rate is faster than at any other period of their life.”
The study followed breastfeeding mothers of 12 infants born at 29 weeks gestation or earlier. The mothers received 1200 mg of DHA (provided by Mead Johnson Nutrition) per day until 36 weeks post-conception. Researchers compared DHA levels in the mothers’ breast milk, mothers’ and babies’ plasma lipids, and daily DHA intakes in the preterm infants from birth to day 49 with a control group of very preterm infants and mothers who did not receive DHA supplements during lactation.
Researchers achieved a 1% DHA content in the milk provided to the preterm before reaching the third week of life and full enteral feeding. “Although there is no difference in the enteral feeding intake at day 49, infants of the DHA group received 55.2 ± 37.6 mg/kg/day of DHA compared with 7.2 ± 11.1 in the reference group,” they wrote. “In infants, the intervention results in a positive significant trend in the DHA plasma concentrations over the study period (p=0.0143) with a significant difference between the two groups at Day 49 (60.3ng/ml ± 23.5 in DHA group (n=12) and 31.7ng/ml ±10.7 in the reference group (n=21), p=0.0014). Changes in the fatty acid composition suggested that intervention did not significantly alter AA and EPA content in preterm’s plasma and mother’s milk.”
In summary, the study demonstrated that DHA levels in the breast milk of mothers who received supplements were almost 12 times higher than levels in the milk of mothers in the control group. Although there was no difference in the enteral (tube) feeding intake among both groups of infants, those in the intervention group received about seven times more DHA than the control group. In addition, plasma DHA concentrations in mothers and babies in the DHA group were two to three times higher than the control group.
Dr. Marc said the study underscored the developmental benefits of DHA supplementation for preterm babies. “In breastfed premature [infants], DHA intake is restricted entirely to the concentration available in mother’s breast milk,” she said. “Further studies must explore the role of DHA intake at all level of child development and growth particularly in at risk infants.
“Our results underline the urgent need for recommendations addressing dietary DHA intake during lactation of mothers of very preterm infants to reach optimal DHA level in milk to be delivered to the baby for optimal growth and neurodevelopment, since the human milk DHA content in mothers not consuming fish during this period is most probably insufficient,” she added.
The study, which was funded by a research grant from the Sick Kids Foundation, was presented at the recent annual meeting of the Pediatric Academic Societies (PAS) in Vancouver, British Columbia, Canada, and is presently under review for publication in the Journal of Nutrition.
Dr. Marc said she and her colleagues are planning to follow this research with a cohort study. They also plan to embark on future studies with the goal of examining the role of DHA on immediate and long term clinical outcome in very preterm infants.