Triplets may face a greater risk of developmental delays during the first two years of life than other children, a new study suggests.
Researchers found triplet infants were more likely to have delays in mental development than similar infants born as single-birth infants or as twins. In addition, the smallest triplets may face the greatest risks.
The findings are reported by Ruth Feldman, PhD, of Yale University (search), and colleagues in the February issue of Pediatrics.
The researchers say that triplets who weigh at least 15 percent less than the heaviest triplet sibling were much more likely to experience delays in mental development; the small triplets also receive less sensitive mothering than their siblings.
Researchers say that infants born as triplets have an increased risk of being born prematurely. Premature infants are at risk of being born at low weight. They could have nerve impairment, mental delays and behavior problems later in life, and have a higher risk of death and disability.
The researchers say their findings are important because the number of triplets born in the U.S. has increased by tenfold since 1980. Yet little research has looked at the long-term development of triplets compared with similarly matched twins and single-birth infants.
Triplets Face Special Risks
In the study, researchers followed 23 sets of triplets, twins, and infants born in single births for two years. They collected data on the infants' birth weight, medical and demographic features and the number of weeks of pregnancy at birth.
At six, 12, and 24 months of age, researchers observed mother-infant interaction and tested the infants' mental development using a standardized test.
The researchers looked at the mothers' sensitivity to their infants in areas such as warm and positive emotions, affectionate tone, resourcefulness at dealing with the infants' negative state, and adaptation to the infants' signals.
Researchers found mothers of triplets showed less sensitivity toward their infants at all the age intervals and their infants were also less socially involved at six and 24 months.
The study also showed that triplets scored lower than the other infants on mental development tests at all intervals.
Researchers say these problems may be related to intrauterine growth factors and to the difficulty of providing sensitive mothering to three babies at the same time.
"Because the numbers of triplets are increasing, the need for financial and social support for parents during the first months of infant life is clear," write Feldman and colleagues. "Without such organized assistance, it cannot be expected that the mother will form the unique, sensitive, individualized relationship that is necessary for these high-risk infants."
By Jennifer Warner, reviewed by Brunilda Nazario, MD
SOURCE: Feldman, R. Pediatrics, February 2005; vol. 115: pp 443-452.