Over the past 40 years, the average age of women having first births has risen, according to a report from the National Center for Health Statistics (NCHS). An analysis of data from the Natality Data File from the National Vital Statistics System (NVSS) has shown that in 2012 alone, there were more than 9 times as many first births to women aged >35 years than there were the 4 previous decades.

Key findings include:

  • The first birth rate for women aged 35–39 increased from 1970 to 2006, decreased from 2006 to 2010, and increased again in both 2011 and 2012.
  • The first birth rate for women aged 40–44 was steady in the 1970s and started increasing in the 1980s; the rate more than doubled from 1990 to 2012.
  • For women aged 35–39 and 40–44, all race and Hispanic origin groups had increasing first birth rates from 1990 to 2012.
  • Since 2000, 46 states and D.C. had an increase in the first birth rate for women aged 35–39.
  • For women aged 40–44, rates increased in 31 states and D.C.

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The report highlighted the increased health risks to older mothers, especially those >40 years old. Overall, first time older mothers are better educated and more likely to have more resources (eg, higher incomes) than those at the youngest childbearing ages. For women aged <30 years, particularly those aged <20 years, first birth rates have declined in the past decade. However, the increase in first births to older mothers from 2000–2012 has been sustained even as total births have gone down.

The CDC and NCHS note how these trends in first births to older women impact population structure such as composition, future growth, lower total fertility, and family size.

For more information visit CDC.gov.