Gestational Diabetes Increasing AmongUS Women

Women in the United States are developing gestational diabetes at a higher rate than a decade ago, and disparities have persisted between White women and women of other races, researchers say.

In a study of 12.6 million women who had given birth, the overall age-adjusted prevalence of gestational diabetes increased from 47.6 per 1000 live births (95% CI, 47.1 – 48.0) in 2011 to 63.5 (95% CI, 63.1 – 64.0) in 2019, for a mean annual increase of 3.7% per year.

“Given that gestational diabetes is associated with increased short-term and long-term risks for individuals and their offspring, the observed trends and disparities may portend a greater burden of future cardiometabolic disease,” warned Nilay S. Shah, MD, MPH, of Northwestern University in Chicago, Illinois, and colleagues in a recent article in the Journal of the American Medical Association. 

Documenting differences by ethnic and racial categories could yield better understanding of the causes behind the trends, the researchers reasoned. Therefore, they analyzed the data on birth certificates collected by the National Center for Health Statistics (NCHS).

They found increases in gestational diabetes in every group analyzed.

Table. Gestational Diabetes Rate by Ethnicity

Although gestational diabetes rates were lower among non-Hispanic Black women than among non-Hispanic White women, non-Hispanic Black women had a higher rate of diabetes before becoming pregnant.

Zeroing in on ethnic subcategories, Shah and colleagues found that absolute rates of gestational diabetes in women giving birth for the first time were highest among women of Asian Indian heritage, increasing from 90.8 (95% CI, 85.9 – 95.9) to 129.1 (95% CI, 124.1 – 134.2) per 1000 live births.

The researchers noted that the trend toward gestational diabetes parallels increasing trends in risk factors such as obesity, inactivity, and poor diet.

Thus, the differences in gestational diabetes rates among ethnic groups could be related to differences in risk factors, they theorized. For example, Hispanic/Latinx women at first live birth had higher body mass indexes and lower educational attainment than non-Hispanic White women, the researchers found. Non-Hispanic Asian women, on the other hand have “dysregulated visceral fat deposition at lower BMI values” than white women.

However, based on previous research, racism could also account for differences among the ethnic groups, write Camille E. Powe, MD, of Harvard Medical School in Boston, Massachusetts, and Ebony B. Carter, MD, MPH, of Washington University School of Medicine in St. Louis, Missouri, in an accompanying editorial. Racism limits access to “housing, healthy food, living environments conducive to physical activity, education and high-quality health care,” they write.

The study’s findings underscore the need for greater efforts to identify women at risk for gestational diabetes, they write. “Because of the strong links between glucose intolerance during pregnancy and future diabetes, these observations ominously foreshadow a potential future increase in diabetes incidence.”

The US Preventive Services Task Force now recommends that pregnant women with no previous diagnosis of diabetes should be screened for gestational diabetes at 24 weeks’ gestation or later.

The study was supported by grants from the National Institutes of Health. Shah reported receiving one such grant. The authors and editorialists have disclosed no relevant financial relationships.

JAMA. Published online August 17, 2021. Full text, Editorial

Laird Harrison writes about science, health, and culture. His work has appeared in national magazines, in newspapers, on public radio and on websites. He is at work on a novel about alternate realities in physics. Harrison teaches writing at the Writers Grotto. Visit him at www.lairdharrison.com or follow him on Twitter: @LairdH