Triplet births in the United States. An epidemic of high-risk pregnancies

OBJECTIVE: To more precisely understand the changes in triplet births in recent years. STUDY DESIGN: Analysis of recent government and medical publications pertaining to triplets. RESULTS: Triplet births are at much greater risk than singletons of poor birth outcomes. More than 9 of 10 triplet births are born preterm (< 37 completed weeks of gestation) as compared with < 1 of 10 singleton infants. The average weight of a triplet newborn (1,698 g) is one-half that of a singleton newborn (3,358 g). The infant death rate for triplet and other higher-order multiple births is 12 times higher than that for singletons (93.7 as compared with 7.8 infant deaths per 1,000 live births). CONCLUSION: Based on their frequency of preterm birth, low birth weight and infant death rate, it is appropriate to characterize all triplet pregnancies as high risk.