A recent article published jointly by Pro Publica and NPR trained a giant spotlight on the rising rates of maternal mortality in the United States.1 It got all of my colleagues talking.  

Though the article hit a nerve especially in the OB community, the trend has not gone unnoticed elsewhere, as recent features in The New York Times, Time Health, and CNN bear witness.  It is a topic that gets people’s attention, but is not so easily understood.

Maternal death is defined as a death while pregnant or within 42 days of delivery. The maternal-mortality ratio is the number of maternal deaths per 100,000 live births2. Data sources for this number may include vital registration, health service records, household surveys, and census.  Accurate comparisons are often difficult due to inaccurate reporting, postpartum deaths not attributed to pregnancy, and lack of accurate medical records.

The Centers for Disease Control and Prevention (CDC) began monitoring US pregnancy-related deaths in 19863.  Since then, the number of “reported pregnancy-related deaths in the United States steadily increased from 7.2 deaths per 100,000 live births in 1987 to a high of 17.8 deaths per 100,000 live births in 2009 and 2011.”3 The 2014 stats are quoted as 23.8 maternal deaths per 100,000 live births.4 The US now has a higher maternal mortality rate than most high-income countries, and it is estimated that half of these deaths are preventable.5 

The CDC collects data by sending requests to all 52 reporting areas (the 50 states, the District of Columbia, and New York City), asking for copies of death certificates for all women who died during pregnancy or within 1 year of pregnancy, and copies of matching birth certificates or fetal death certificates when available. However, despite the effort to collect this data, good data and analysis of maternal-health outcomes5 is still lacking.

Why is maternal mortality increasing in the US? Like most complicated issues, there is no simple answer. One issue has to do with the statistics themselves.  Maternal mortality numbers go up and down as ICD codes and use of computerized linkages change. Improved detection and reporting of pregnancy-related deaths in the US also could have contributed to the rising rates.

The quality of medical care certainly plays a role.5 Some argue that inconsistent obstetric practice and lack of standardization of care is a contributing factor. Many studies show that pregnant women in the US are becoming increasingly unhealthy, evidenced by their higher incidence of obesity, diabetes, hypertension, and chronic heart disease. Spikes in the rates also have been associated with specific illnesses, such as the influenza A (H1N1) pandemic in 2009-2010.3 

Fifty percent of pregnancies in the US are unplanned, which means that women may not be as healthy as they could be when they become pregnant. And pregnancy can be a dangerous condition in and of itself.