As diabetes during pregnancy grows more common, experts point to a need for preventive care

Gestational diabetes is on the rise, climbing 30% between 2016 and 2020, according to a new study published Tuesday by the Centers for Disease Control and Prevention.

“There is a growing maternal health crisis in the United States, and gestational diabetes is an important and common complication that requires new focus,” said Sadiya Khan, an assistant professor of medicine and preventive medicine at the Northwestern University Feinberg School of Medicine, who was not involved in the new study. “That inflection point there is really striking and something that we’re going to want to follow up [on].”

During pregnancy, particularly in the third trimester, the body purposefully muffles insulin signaling. To meet the increased energy demands of the fetus, hormones such as estrogen, cortisol, and human placental lactogen may increase the blood sugar to more than twice their normal levels. Though normal in moderation, this process sometimes goes haywire and develops into gestational diabetes, which can lead to difficulties during labor and ongoing health issues in infants.

The new analysis of 3.25 million birth records follows a string of studies that suggest gestational diabetes has become increasingly prevalent over the last three decades, which may be attributable to long-standing trends in the rising age of women giving birth, changing ethnic demographics of mothers, and, before 2014, the growing rate of twin births.

“It certainly confirms what a lot of people have seen so far,” said Elizabeth Morgan, a maternal-fetal medicine specialist at Baystate Medical Center in Springfield, Massachusetts, who was not involved in the study. “And it’s certainly concerning in terms of what it means for future pregnancies from this point.”

Margaret Delaney, a nurse at Baystate Medical Center who was not involved in the study, has seen that rise first-hand. She used to manage 40 to 60 patients with gestational diabetes at Baystate’s maternal-fetal clinic 15 years ago. Now, she sees 130 to 140 patients at any given time, an uptick that has primarily happened over the past 5 years. “Our numbers for gestational diabetics in the last few years have gone through the roof,” she said. “We can’t manage the amount that we have.”

The CDC analysis showed that cases increased 13% during the first year of the pandemic alone, a much larger spike than the previous annual increases of about 5%. Experts say that the sharp increase during Covid may be because the disease accelerated people’s adoption of a sedentary lifestyle and led to pandemic-related physical and emotional stress. “Either, it’s from Covid-19 itself, but probably more likely from stress, from people being more sedentary,” said Morgan. And experts are concerned outcomes in 2021 may be worse, when Covid hit harder.

If anything, the authors and experts said, the new finding is likely an undercount. Relying on birth certificate data, which the CDC study did, can miss cases that are not captured by a physician on those forms. “If you think about it, somebody who’s doing 20 deliveries in a night, or ten deliveries in a night, is just kind of trying to get those reports and certificates out there,” said Morgan. “They’re not paying as much attention to some of those details.”

The CDC lists several risk factors for gestational diabetes, including a family history of diabetes, being overweight, and having had a baby over 9 pounds. For Asian Americans, the condition is nearly twice as common, including a rate of nearly 17% for Asian Indians — the equivalent of one in six live births. In 2020, there was an average of 7.8 cases per 100 births.

Experts said there is a need for earlier diagnosis and, generally, far more awareness about the condition among patients and their providers. “We often wait till this 24- to 28-week period to identify gestational diabetes,” said Khan. “But there may be some undiagnosed babies or prediabetes that precedes that, that could be identified in early pregnancy.”

Studies are rarer in the U.S., but a study at a hospital in the capital of Samoa found that one-fifth of patients did not think diabetes could arise during a pregnancy and one-quarter of patients were unsure. Anecdotally, Morgan feels that fewer than half of her patients come in aware of gestational diabetes. “A lot of people find out about a lot of these things during their pregnancies,” she said. “We need to move towards preventative health care. And I just don’t think we’re there yet.” Experts said some interventions, such as physical activity and changes in diet, help in prevention and treatment, but are not used widely enough.

Other experts see significant problems with treatment, starting with the need for more trained providers to match the increase in gestational diabetes diagnoses. “I’m concerned at a national level [about] the number of medical providers who are trained to take care of people with gestational diabetes,” said Irl Hirsch, an internist, endocrinologist, and professor at the University of Washington Medicine Diabetes Institute, who was not involved in the study. It is an issue that is also relevant to caring for patients with type 1 and type 2 diabetes, he said. But “if we look at these curves that were in that article, are we going to have enough providers, not just the OB-GYN, but also family practice who are trained to take care of this?”

“We need to make sure that all of the providers who manage these pregnant women have state-of-the-art training for gestational diabetes,” he added. “Right now, I don’t think that’s the case.”

For patients, there are additional barriers to care, including being able to afford enough glucose test strips and insulin. “It’s exceptionally hard right now, depending on a patient’s insurance,” Morgan said. 

The study authors, for their part, plan to look at trends in type 1 and type 2 diabetes while following up on the gestational diabetes data next year. “We’ll continue to monitor and publish on trends on gestational diabetes in the future, to see what is going on with the rate,” said Elizabeth Gregory, a health scientist at the CDC and first author of the new report. “I think it’s an important thing to continue to monitor.”

Experts are particularly worried that too many people still view gestational diabetes as a short-term problem, rather than an issue with ripple effects for the next generation. Up to 70% of mothers with gestational diabetes develop type 2 diabetes within 20 years. Their children are more likely to have type 2 diabetes, too. Diabetes, in turn, doubles or triples the risk of developing heart disease and stroke, as well as of death due to cardiovascular diseases.

It is an issue experts are concerned will only get worse as the birth rate ticks up and as maternal health care services are expected to grow more strained, especially in under-resourced communities.

“This is a growing problem, and one that requires focused attention and increased awareness,” said Khan. “This issue does not resolve with the pregnancy and is really one that we need to focus on before, during, and after pregnancy for those at risk.”