News: Pregnancy checkbox on death certificates changed rate of maternal deaths, data shows

The addition of the pregnancy checkbox on death certificates in 2003 correlated with an increase of 6.78 maternal deaths per 100,000 live births in the U.S., according to a new analysis published in JAMA Pediatrics. Since then, the maternal death rate has remained consistent between 6.75 and 10.24, except for a brief jump to 18.86 in 2021 that is attributed to the COVID-19 pandemic; the rate dropped back down to 10.23 in 2022, MedPage Today reported.

Researchers used data from both the National Vital Statistics System and the CDC Wide-Ranging Online Data for Epidemiologic Research (WONDER) database. They calculated maternal deaths using various ICD codes including those for:

• Maternal mortality, or deaths within 42 days postpartum
• Late maternal mortality, or deaths between 43 and 365 days postpartum
• Unspecified maternal mortality, or deaths from unspecified causes
• Maternal mortality excluding cause unspecified, or cases without unspecified maternal death codes

The study also analyzed infant and fetal death rates, extracting all-cause deaths for those younger than one year as well as deaths at 20 weeks' gestation or more (excluding terminations of pregnancy). They found infant deaths decreased from 6.93 in 2000 to 5.44 in 2020, and then slightly increased in 2021 to 2023; fetal death rates dropped from 6.28 in 2005 to 5.53 in 2022.

“Our work is the first to quantitatively separate out the effect of change in data collection from actual trends in maternal mortality,” co-author Robin Park, MSc, of the University of Oxford, told MedPage Today. “Adjusting for the change in data collection, we find that the rate of maternal mortality has been relatively constant since 2000.”

Park also noted that anecdotal evidence suggests that the pregnancy checkbox can make coders more likely to add a maternal or pregnancy-related cause of death, so it has been difficult for researchers to accurately track trends due to the changes in data collection. Across all time periods, however, the researchers found notable racial disparities in maternal and infant mortality.

For instance, maternal death rates for Native American or Alaska Native women rose during the pandemic, from 10.70 (2011-2019) to 27.47 (2020-2022). Black women had the highest maternal mortality rates, approximately three times the rate of white women in each time period the researchers analyzed.

Editor’s note: To read MedPage Today’s coverage of this story, click here. To read the JAMA Pediatrics study, click here.