Pregnant women today are more likely to have chronic conditions that could cause life-threatening complications than at any other time in the past decade — particularly poor women and those living in rural communities, a new Michigan Medicine study suggests.

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Using a national sample of 8.2 million childbirth deliveries over 10 years, researchers analyzed the prevalence of common chronic conditions, including asthma, diabetes, hypertension, heart disease and substance-abuse disorders.

Although frequency of these conditions increased over time among every socio-economic group studied, the largest spikes occurred among women from rural and low-income communities and among patients with deliveries funded by Medicaid.

The findings were published in The Green Journal, the official publication of the American College of Obstetricians and Gynecologists.

"Chronic conditions that increase the risk of adverse health outcomes for moms and their newborns are increasingly prevalent among childbearing women," says lead author Lindsay Admon, M.D., an obstetrician-gynecologist at University of Michigan Von Voigtlander Women's Hospital and a clinician-scholar at the U-M Institute for Healthcare Policy and Innovation.  

"Historically, the leading causes of maternal morbidity and mortality in the U.S. have been related to delivery, such as infection or hemorrhage. For the first time in our country, we are seeing complications from pre-existing conditions causing the most harm."

A growing problem

The research stems from stunning reports over recent years finding that the U.S. continues to defy global trends as one of the only developed countries with a rising maternal mortality rate. The fastest rising, and now most common, cause of maternal death in the country is complications occurring as a result of a mother's pre-existing, chronic condition (such conditions are now attributed to half of all maternal deaths in the U.S.)

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Michigan researchers identified at least one chronic condition among 10 percent of women delivering babies in 2013-14 (92 per 1,000 hospitalizations). That's an increase of nearly 40 percent from 2005-06 (when it was 67 per 1,000).

Although less common, cases involving multiple pre-existing, chronic conditions increased from 5 to 8 per 1,000 deliveries over the same period.

"The highest prevalence of chronic conditions tied to maternal morbidity and mortality was identified among already vulnerable populations—those living in rural areas and in the poorest communities," says Admon.

"These findings highlight stark and growing health disparities in maternal health."

Among the most concerning trends was the increase in substance-abuse disorders. Among all deliveries in 2005-06, substance abuse was identified in 13 per 1,000 hospitalizations, compared to 20 per 1,000 in 2013-14.

For rural women, that rise was far more dramatic: It increased from 11 to 25 per 1,000 deliveries.

As the nation faces an opioid epidemic, Admon says more resources must be devoted to addressing substance abuse, particularly for childbearing women in rural communities that often do not have the same access to care for substance use disorders as urban areas.

Taking early action

The new study underscores the need to address pre-existing conditions among childbearing women during prenatal care, Admon says. She notes for women who are on Medicaid, which finances half of all births in the United States, insurance coverage usually lasts from conception to 60 days postpartum.

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"During prenatal care, we have the unique opportunity to have frequent contact with a patient throughout her pregnancy and postpartum recovery.  Ideally, in addition to addressing obstetric care, we can also use this time to help her optimize her long-term health," Admon says. "This is especially important for the growing segment of the population with chronic conditions and among those who may lose insurance coverage between pregnancies."

Admon notes that having conditions such as diabetes and hypertension under control not only benefits women but also their newborns, who as a result also are at an increased risk of adverse outcomes, including poor growth, preterm delivery and stillbirth.

In 2005, 23 mothers per 100,000 live births died from complications related to pregnancy or childbirth in the U.S. In 2015, that number rose to 25. That compares to less than 9 deaths per 100,000 births in the United Kingdom and less than 7 in Canada.

"We wanted to better understand the trends, prevalence and socio-economic distribution of chronic conditions among women giving birth in the United States to help providers and policymakers better take care of this population," Admon says. "In describing what populations are more likely to have certain conditions, we can better understand where interventions may have the most impact." 

Physicians should seek to diagnose and address chronic conditions as early as possible, Admon says.

"As maternal health providers, we need to be aware of the increasing burden of chronic conditions complicating our patients' pregnancies and deliveries," she says. "That means actively screening for these conditions and educating our patients about optimal management both during pregnancy and for the long term."

"Identifying and managing chronic conditions at the beginning of a pregnancy gives women the best chance of having a healthy pregnancy and the outcome we always strive for — a healthy mom and healthy baby."