THURSDAY, Aug. 22, 2002 (HealthDayNews) -- Pregnant women who eat more of a key fatty acid found in fish have babies who show signs of more mature brain development, a new study has found.
Those newborns whose mothers had more of it in their blood had heartier sleep patterns in the first 48 hours after delivery compared to those whose mothers consumed less of the compound, known as docosahexaenoic acid (DHA).
Infant sleep patterns are thought to reflect the maturity of their nervous system, and have been correlated with more rapid development in their first year of life. A report on the findings appears in the September issue of the American Journal of Clinical Nutrition.
An omega-3 fatty acid, DHA, along with another substance, arachidonic acid (AA), are key building blocks in breast milk that contribute to healthy brain and eye development. Indeed, acknowledging the advantages of these compounds, two of the nation's largest formula makers, Ross Products and Mead Johnson Nutritionals, announced earlier this year that they would begin adding them to select brands.
The two substances are also passed from mother to fetus across the placenta. Some 70 percent of brain cell development takes place during gestation.
In the new study, Carol Lammi-Keefe and her colleagues at the University of Connecticut compared DHA levels and newborn sleep patterns in 17 women and their babies. Ten of the women had high blood concentrations of DHA -- considered to be more than 3 percent of their total circulating fatty acids -- while seven had less than that amount.
Lammi-Keefe's group didn't ask the women about their diets. None of the subjects in the study had DHA levels that reflect eating three or more fish meals a week, what many experts recommend. Other foods, like eggs and red meat, contain modest amounts of the nutrient, but cold-water fish such as tuna and mackerel are considered the best source.
Women with low DHA were more likely to be minorities and to have received fewer years of education. They were also five years younger, on average, than those in the high DHA category -- 24 versus 29 years.
All the babies were delivered vaginally, and none of the women had been given drugs known to make newborns lethargic, the researchers say.
Using a motion-sensing pad to measure breathing and movement during sleep cycles, the researchers found babies of women in the low-DHA group had less advanced sleeping patterns than the other infants. They had a greater ratio of "active" to "quiet" sleep, spent more time transitioning between sleeping and waking, and spent less time fully awake than those of women with higher blood levels of the fatty acid.
"As an infant matures, normally you would see the infant spending more time in a wakeful state," Lammi-Keefe says. "Infants born to mothers with more DHA have sleep characteristics of a more mature central nervous system compared with the infants of mothers with lower DHA levels."
The researchers are now organizing a study that will look at dietary intake of DHA in pregnant women. It will follow their children over the course of a year to assess the substance's impact on development. Lammi-Keefe says she hopes to enroll between 140 and 160 women in the project.
June Machover Reinisch, director emerita of the Kinsey Institute and a child development expert, says the findings seem to echo the importance of breast feeding for optimal infant growth. However, she notes it's difficult to draw meaningful conclusions from the research.
After all, many factors, from method of delivery and the use of anesthesia during labor to the infant's gender, can influence a newborn's wakefulness.
"We have to be flexible in our definition of development," Machover Reinisch says. "With the child who sleeps not as well at two days, it may be related to the DHA, but it doesn't necessarily mean that there's going to be a problem with that child."
Researchers have correlated newborn sleep states with performance on mental and motor developmental tests at 9 months of age. However, both Lammi-Keefe and Reinisch say there's no way to predict whether a child with less mature sleeping habits in the first week of life will be anything other than healthy.
What To Do
For more on fatty acids and infant development, try Infant Canada. For more on infant sleep states, try Lamaze.com
