California Maternal Mortality

Over half a million women give birth each year in California --- almost one in eight births nationally.   After several decades of declining rates of maternal mortality in California, rates began to rise in 1999 and proceeded to double in the next seven years.

Rates of maternal deaths in California rose from 8.0 deaths per 100,000 live births in 1999 to 16.9 deaths per 100,000 live births in 2006. Rates dropped slightly to 11.0 in 2007 but rose again to 14.0 in 2008 (see Figure below).

Figure 1: Maternal Mortality Rate, California residents; 1970-2008

Although there were fluctuations from year to year, on average there was a statistically significant increase in annual maternal mortality from 1999 to 2008. (REF 3,4)  The significant rise remains when maternal deaths among African-Americans are excluded from the calculation, suggesting that rising maternal mortality rates in California are not wholly explained by rising rates among African-American women.

When the statewide data is presented as a three-year moving average, the annual fluctuations inherent to rates for rare events disappears and the upward trend in maternal deaths is more clearly evident (see Figure below).

For graphs on Maternal Mortality Rates for California Residents by Race/Ethnicity, and Age, click here. 

 

REFERENCES
1. National Report Card on Women's Health: State Ranking for Maternal Mortality. http://hrc.nwlc.org/Status-Indicators/Key-Conditions/Maternal-Mortality-Rate.aspx. Accessed June 12, 2009.
2. WHO. Trends in maternal mortality: 1990 to 2008 estimates developed by WHO, UNICEF, UNFPA and The World Bank, World Health Organization 2010, Annex 1. 2010. http://whqlibdoc.who.int/publications/2010/9789241500265_eng.pdf.

3. Armitage P. Tests for linear trends in proportions and frequencies. Biometrics. 1955;11:375-386.
4. Kuhn L, Davidson L, Durkin M. Use of Poisson regression and time series analysis for detecting changes over time in rates of child injury following a prevention program. American Journal of Epidemiology. 1994;140(10):943-955.