Maternal Mortality Due to Cardiac Disease in Pregnancy.

Maternal mortality worldwide has vastly improved over the last several decades. Unfortunately, maternal mortality in the United States has been increasing and now cardiovascular conditions are the leading case of maternal death. The calculation of maternal mortality ratios and pregnancy-related mortality ratios is accomplished by several different organizations and this data collection is often complex, tedious, and poorly understood. Here we review the history of maternal mortality in the United States and aim to better understand how this data are collected.