Deaths from pregnancy-related causes, which usually occur around the time of childbirth, have risen dramatically in the United States in the last decade. In a report released Tuesday, a committee investigating such deaths in California cited an increase in caesarean-section births as a major contributor to the disturbing trend. The report was issued by the California Pregnancy-Related and Pregnancy-Associated Mortality Review, a committee of experts who investigated the increase in maternal mortality. Deaths related to pregnancy in California have risen from 8.0 deaths per 100,000 live births in 1999 to 14.0 deaths per 100,000 births in 2008. The report reflects only data from 2002 to 2003 but shows a marked change in the safety of giving birth in California, especially for black women and poor women.