California Pregnancy-Associated Mortality Review: California Pregnancy-Related Deaths

Maternal mortality is a key indicator of population health. Deaths in pregnancy and postpartum should be rare events, so routine and accurate surveillance of pregnancy-related deaths is an essential public health responsibility.

California Pregnancy-Related Deaths, 2011-2019

Released in June 2022, data from the California Pregnancy Mortality Surveillance System (CA-PMSS) provides the most accurate information on California’s pregnancy-related deaths (including those up to one year after the end of pregnancy) occurring from 2011 through 2019. Highlights include:

• California’s pregnancy-related mortality ratio (PRMR) in 2019 was 12.8 deaths per 100,000 live births and was lower than the PRMR of 16.1 in 2018. California’s PRMR began to rise gradually in 2013 and peaked in 2018.
• California’s PRMR was consistently lower than the U.S. PRMR from 2011 through 2017 (latest available national data).
• The rate of pregnancy-related deaths from hypertensive disorders of pregnancy (preeclampsia/eclampsia) decreased significantly in 2017-2019. For the first time, hypertensive disorders are no longer among the top five leading causes of pregnancy-related deaths in California.
• Cardiovascular disease continued to be the leading cause of pregnancy-related deaths in 2017-2019, followed by hemorrhage, sepsis or infection, thrombotic pulmonary embolism, and amniotic fluid embolism.
• Racial/ethnic disparities in the rates of pregnancy-related deaths narrowed in 2017-2019 but persist. The PRMR for Black birthing people was three to four times higher than the PRMRs for all other racial/ethnic groups in California. The PRMRs for Asian/Pacific Islander and Hispanic/Latina birthing people gradually increased from 2011 through 2019.
• The gap in the rates of pregnancy-related deaths by type of health coverage increased significantly from 2011 through 2019. In 2017-2019, the PRMR for those covered by Medi-Cal or another public program was nearly double the PRMR for those with private insurance (17.5 vs. 9.1 deaths per 100,000 live births). In 2011-2013, the PRMR did not differ by type of health coverage.
• From 2011 through 2019, the rate of pregnancy-related deaths was consistently higher for birthing people living in less advantaged community conditions than for those living in more advantaged community conditions.

California Pregnancy-Related Deaths, 2008-2016

Released in September 2021, a California Pregnancy Mortality Surveillance System (CA-PMSS) report finds that California’s rate of pregnancy-related deaths has remained low compared with the U.S. rate and has been largely stable from 2008 to 2016. However, racial/ethnic disparities in pregnancy-related mortality ratios appear to be worsening, particularly among Black women. Black women were overrepresented among pregnancy-related deaths from all causes, especially deaths that occurred in pregnancy prior to birth or after delivery hospitalization.

While California has made progress to reduce maternal mortality through investment in maternal health programs, strong leadership and engagement of the maternity care community and targeted hospital quality improvement, more needs to be done to narrow racial/ethnic disparities.

The California Pregnancy Mortality Surveillance System (CA-PMSS) is a statewide surveillance of deaths among Californians who were pregnant within the prior year. Funded by the federal Title V Maternal and Child Health Block Grant, the Maternal, Child and Adolescent Health (MCAH) Division of the California Department of Public Health (CDPH) initiated CA-PMSS and relies on a collaboration with three key partners: The Public Health Institute, Stanford University’s California Maternal Quality Care Collaborative, and a volunteer review committee of experts.

Explore key findings from the report:

Pregnancy-related deaths in California:

• In 2008-2016, 1,934 women died while pregnant or within one year of the end of a pregnancy; 31% (608) of these deaths were related to pregnancy or its management.
• California’s annual pregnancy-related mortality ratios remained low and largely stable in 2008-2016, fluctuating between 9.5 and 14.9 deaths per 100,000 live births. One exception was a spike in pregnancy-related deaths caused by influenza A (H1N1) during the 2009 pandemic, which resulted in an elevated pregnancy-related mortality ratio of 17.1 in 2009.

By cause and timing to death:

• The top five leading causes of pregnancy-related deaths were cardiovascular disease (28%), sepsis or infection (17%), hemorrhage (15%), hypertensive disorders (13%) and thrombotic pulmonary embolism (7%).
• Eighteen percent (18%) of pregnancy-related deaths occurred while pregnant, and of the remaining 82% that occurred after pregnancy ended, nearly half (44%) of the deaths were within six days of childbirth (or end of pregnancy), 24% occurred 7-42 days after pregnancy ended and 14% were 43-365 days after pregnancy. Timing to death varied greatly depending on the cause of death.

By sociodemographic and place-based characteristics:

• Pregnancy-related mortality ratios were elevated for women with the following characteristics: older age (35 years or older), pre-pregnancy obesity (body mass index 30 or greater), public insurance (e.g., Medi-Cal) and no high school diploma.
• The pregnancy-related mortality ratio was highest for women living in the least advantaged communities (16.4 deaths per 100,000 live births), more than twice the mortality ratio for women living in the most advantaged communities (6.8).
• Pregnancy-related mortality ratios varied by geographic region, from 10.8 to 17.8 deaths per 100,000 live births; the Southern Central Valley region (includes Fresno, Kern, Kings, Madera, Mariposa, Merced, Stanislaus, Tulare and Tuolumne counties) had the highest pregnancy related mortality ratio of 17.8.

By race/ethnicity:

• Racial/ethnic disparities in pregnancy-related mortality ratios widened between 2008 and 2016. From 2014-2016, the pregnancy-related mortality ratio for Black women was 56.2 deaths per 100,000 live births, four to six times greater than the mortality ratios for women of other racial/ethnic groups including White (9.4), Hispanic (11.0) and Asian/Pacific Islander (13.3).
• Black women were overrepresented among pregnancy-related deaths from all causes, especially deaths that occurred in pregnancy prior to birth or after delivery hospitalization (7-42 days and 43-365 days after pregnancy ended).Hispanic/Latina women were the least likely to die during pregnancy or the late post-pregnancy periods.

Originally published by The California Pregnancy Mortality Surveillance System