For decades, biology characterised the pregnancy's risk zone as high blood pressure, serious bleeding, infection, and heart issues. However, a major new study from Columbia University calls into question that notion. The research shows that the primary causes of mortality among pregnant and newly delivered women in the United States are unintentional drug overdose, homicide, and suicide, rather than medical issues. 

The study, published in the New England Journal of Medicine, looked at death certificate data from pregnant and postpartum women who died within 42 days of birth between 2018 and 2023. 

The investigation revealed that accidental overdose was the top cause of death, accounting for 5.2 fatalities per 100,000 births. Homicide and suicide followed, accounting for 3.9 fatalities per 100,000 births. More than half of all overdose and violence deaths occurred during pregnancy. In contrast, the following most common reasons – cardiovascular disease, infection, hypertension, and haemorrhage – were more prevalent in the immediate postpartum period: cardiovascular disease, infection, hypertension, and haemorrhage. 

"Overdose and violence are not typically on our radar when it comes to thinking about approaches to reducing maternal morbidity and mortality, but these events are far more common among pregnant and postpartum women than we think," says Hooman Azad, the study's leader and a maternal-foetal medicine fellow in the Department of Obstetrics and Gynaecology at Columbia University Vagelos College of Physicians and Surgeons. 

Maternal mortality refers to deaths resulting from pregnancy or childbirth. Maternal morbidity refers to serious disease or difficulties during pregnancy. Traditionally, public health programs have concentrated on preventing physical consequences, like preeclampsia (a hazardous increase in blood pressure) and excessive bleeding. 

The study indicates that this model may have a clinical blind spot. 

Is there an increased risk of suicide or overdose during pregnancy? The results do not indicate that pregnancy directly causes these incidents, but it does reveal that women are sensitive during this time. Regular medical interaction gives opportunities for detection that might otherwise be missed. 

Why are maternal fatalities increasing despite improved hospitals? The general maternal death rate remained relatively stable during the six-year period, with the exception of an increase during the COVID-19 pandemic. However, while medical therapy of traditional problems has improved, social reasons such as violence and substance abuse are now responsible for an increasing proportion of deaths. 

Racial differences were also present. White women were more likely to experience accidental overdoses and suicide, but Black women were more likely to commit homicides. Moreover, over three-quarters of violent deaths used weapons. 

How prevalent is domestic violence when pregnant? The study did not explicitly quantify prevalence, but it recognised homicide as a major cause of death. This raises problems about screening for intimate partner violence during prenatal visits. 

"The take-home message is that we may not do as good a job in screening for drug use and intimate partner violence among our pregnant patients as we do for medical complications," adds Azad. "We have an opportunity to refocus our efforts on preventing drug overdose and violence with multidisciplinary care that includes referrals to mental health care and social services throughout pregnancy—which could save hundreds of lives." 

Psychosocial screening, which includes routine examinations for mental health distress, substance use, and home safety, is often done only once. The data indicate that screening may need to be repeated during each trimester. 

Can doctors identify mental health issues early in pregnancy? Experts believe they can—but only if systematic protocols exist. 

The study redefines maternal safety. It suggests that protecting pregnant women now necessitates not only monitoring blood pressure and foetal heart rate but also considering mental health, addiction risk, and personal safety.