Health >> Infant Mortality >> Mother's Age

Babies born to mothers age 25-39 were more likely to survive their first year of life than infants with younger mothers.

If a baby dies before his or her first birthday, that death is counted as an infant death. The number of infant deaths per 1,000 live births is known as the infant mortality rate, and is widely regarded as an indicator of the overall health of a community. 

In 2010, the infant mortality rate for King County was 4.2 deaths per 1,000 live births. Averaging 5 years of data to make demographic comparisons, the 2006-2010 rate was 4.1 per 1,000.

Infants born to mothers aged 25 to 39 had the best chance of surviving past their 1st birthday.

  • Infant mortality was more than 1.5 times higher among babies born to younger mothers.
  • The risk of death was also higher for babies born to older mothers, but the difference did not reach statistical significance in analysis of the most recent data.
  • Infant mortality was highest among teen mothers (<18 years old), but this rate was very unstable.  From 2006 to 2010, an average of 3 infant deaths per 1,000 live births occurred to mothers in this age group.