Triplets and higher-order multiple births. Time trends and infant mortality

Area of Science:

• Reproductive Health
• Neonatalogy
• Epidemiology

Background:

• Higher-order multiple births (triplets and higher) have shown changing incidence rates.
• Infant mortality rates for multiple births require ongoing monitoring and comparison to singletons.
• Understanding trends in multiple births is crucial for public health planning.

Purpose of the Study:

• To analyze trends in higher-order multiple births (triplets and higher) in the US from 1972 to 1989.
• To compare infant mortality rates of higher-order multiples with singletons (1983-1985).
• To assess changes in infant mortality for higher-order multiples from 1960 to 1983-1985.

Main Methods:

• Population-based analysis of US live births (1972-1989) and infant deaths (1960, 1983-1985).
• Utilized national natality files and linked birth/infant death data sets.
• Calculated rates of higher-order multiple births per 100,000 live births.

Main Results:

• Higher-order multiple birth rates increased by 113% (white mothers) and 22% (black mothers) between 1972-1974 and 1985-1989.
• Increases in white mothers were age-specific, particularly in older age groups and more educated women.
• Infant mortality for higher-order multiples (1983-1985) was 15 times that of singletons, primarily due to lower birth weight; weight-specific mortality was comparable or lower.

Conclusions:

• Increased use of ovulation-inducing drugs is a likely driver of the rise in higher-order multiple births.
• Despite declining mortality, the increased incidence necessitates greater medical and social support for affected families.