The infant mortality rate in the United States has fallen to an all-time low, while life expectancy at birth has reached a new high, at 76.1 years.
In 1996, there were 7.2 infant deaths per 1,000 live births, according to a summary of preliminary 1996 government statistics published in the December issue of Pediatrics, the journal of the American Academy of Pediatrics. That’s 5 percent lower than in 1995 and the lowest ever recorded in the United States.
The life expectancy for children born in 1996 was 76.1 years, or 0.3 years longer than in 1995, according to the summary, which was based on data from the National Center for Health Statistics and the Census Bureau.
Medical developments were the main reasons for the decline in the infant mortality rate, said lead author Dr. Bernard Guyer of Johns Hopkins School of Hygiene and Public Health in Baltimore.
But while scientific progress is keeping more children alive, it is also contributing to the growing number of infants with low birth weights - 7.4 percent of all births in 1996, up from 7.3 percent in 1995 and the highest level reported since 1975.
The traditional risk factors did not appear to be to blame. Smoking during pregnancy was down, and early prenatal care rates were up.
Instead, the trend was attributed to increased use of fertility treatments and the growing number of women in their 40s giving birth.
Fertility treatments and giving birth late in life raise the chances of multiple births, which almost always result in premature, underweight babies. Also, individual babies born to older women are more likely to be underweight.
“It is a problem we have created ourselves with our technology,” Guyer said.
The number of multiple births has been increasing by an average of 2 percent per year since 1980, according to the report.
Despite its steady decline in infant mortality rates, the United States continues to rank poorly compared with other industrialized countries because of the number of babies born weighing less than 5.5 pounds. Underweight babies accounted for nearly two-thirds of all infant deaths in 1995.
The report also noted the fifth consecutive drop in the birth rate for teenagers in 1996, including the first substantial decline for Hispanic teens.
Preliminary 1996 statistics indicate that the level of teen births dropped 4 percent to 54.7 births per 1,000 women ages 15 to 19. The rate for Hispanic teens fell 5 percent to 101.6 per 1,000.
The birth rate for unmarried women also declined 1 percent in 1996 to 44.6 births per 1,000 unmarried women. This continues a trend noted last year for the first time in two decades.