LOS ANGELES (AP) — California health officials say maternal mortality is on the rise, with African-American mothers roughly four times more likely to die from pregnancy-related causes than women in all other racial or ethnic groups.

The California Department of Public Health study released Tuesday says the rate of maternal deaths in 1999 was eight deaths per 100,000 live births and by 2008 that number had risen to 14 deaths per 100,000.

A number of factors affect the statistics, including better tracking, increasing age of mothers and increasing prevalence of maternal chronic conditions such as obesity.

The study notes cesarean section delivery rates have been rising simultaneous to increases in maternal morbidity.

C-sections are surgical procedures, with higher risk of complications like infection, bleeding or blood clots when compared to vaginal births.

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