Gestational Diabetes: Latest Research Updates
Key takeaways:
- Gestational diabetes (GDM) was a hot topic of discussion at this year’s American Diabetes Association (ADA) scientific sessions.
- Medical journal The Lancet published a series of papers on gestational diabetes that were presented at ADA 2024. The papers challenged current approaches to managing the condition and called for earlier intervention to avoid complications.
- Other gestational diabetes research highlights this year included a push for CGM use and CGM metrics in all gestational diabetes pregnancies, use of CGM on GDM newborns, and a potential need for tighter time in pregnancy range targets.
One of the most prominent highlights at this year’s American Diabetes Association conference was the significant research headway made in the study of gestational diabetes mellitus (also known as GDM). Gestational diabetes is a type of diabetes that occurs in those without a prior diagnosis of diabetes where blood glucose levels are higher than normal during pregnancy; this condition can impact both the mother and the baby.
GDM was a hot topic of discussion at many presentations: Some presenters lobbied for earlier screening of the condition; others discussed the use of continuous glucose monitors (CGMs) in gestational diabetes; and a growing body of research focused specifically on the outcomes of both the newborn child as well as the pregnant woman. Read on for some of the top gestational diabetes research highlights out of this year’s conference.
Screening earlier and monitoring women post-pregnancy
Peer-reviewed medical journal The Lancet released a new series on gestational diabetes in tandem with the conference. The authors of the new series, who presented their findings in several ADA sessions, discussed characteristics associated with GDM before, during, and post-pregnancy; the prevalence of gestational diabetes; and the idea of viewing gestational diabetes as a life course disease that will affect patients far beyond the duration of a pregnancy.
The series authors, who urged the industry to “shift to a holistic life-course approach in how we manage the disease,” had several main takeaways.
Detecting GDM earlier to avoid complications
Detecting and managing diabetes much earlier in pregnancy can not only prevent complications during pregnancy but also impact long-term outcomes, presenters said.
While the World Health Organization’s current approach calls for GDM testing at 24-28 weeks of pregnancy, presenters urgently stressed that screening needs to begin significantly earlier – before 14 weeks of gestation – to reduce not only prenatal complications. They cited TOBOGM, a study that showed treating GDM before week 20 reduced the risk of severe pregnancy complications like preterm birth, low birthweight, stillbirth, and respiratory distress.
Changes in body function due to GDM occur not only in early pregnancy but also before pregnancy
One of the papers presented detailed new evidence suggesting gestational diabetes and its changes in physiology can occur not only in early pregnancy but also before pregnancy, with metabolic changes detectable as early as before 14 weeks. Thinking about prevention of GDM pre-pregnancy, the presenters said, is crucial to minimizing gestational diabetes risk.
An earlier GDM diagnosis for better lifelong health outcomes
Screening for GDM also needs to happen earlier to reduce the risk of developing other health conditions later in life beyond pregnancy, scientists said. These conditions include obesity, high blood pressure, high cholesterol, liver disease, and cardiovascular disease.
As metabolic conditions continue to rise worldwide and type 2 diabetes increases in women of reproductive age, the authors argued that a better understanding and monitoring of pre-pregnancy, early pregnancy, late pregnancy, and post-pregnancy changes in the mother and fetus is needed. This lifelong approach needs to be taken with an individual’s genetics, lifestyle, and environment in mind.
“The benefits of early GDM detection are clear – we can keep mothers and babies healthier during pregnancy and hopefully continue that path for a lifetime. What is needed now is earlier testing and an approach to managing GDM that takes the available resources, circumstances, and personal wishes of the patient into consideration,” said Series author Dr Helena Backman of Örebro University in Sweden.
A louder call for CGM use and its metrics
While the latest ADA Standards of Care recommends CGM use in all pregnant women with type 1 diabetes, the same standard has not yet been set for pregnant women with GDM, and many pushed for the use of CGMs in all cases of gestational diabetes.
Prof. Eleanor Scott of the University of Leeds highlighted data that illustrated how gestational diabetes patients often use blood glucose meter testing inconsistently – yet another reason why CGMs should be used across the board in pregnancies that have been complicated by gestational diabetes, she argued in one debate. The use of a CGM in gestational diabetes, she argued, is as inevitable as the move from urine glucose testing to blood glucose meters more than 40 years ago.
A potential need for stricter GDM time in range targets
While the latest international consensus established a time in pregnancy range (TIPR) of 63-140 mg/dl, many researchers brought up the topic of adopting a tighter, more stringent time in pregnancy range.
At last year’s ADA conference, Dr. Celeste Durnwald presented results of the GLAM study, which evaluated a narrower time in range target of 63-120 mg/dl for participants with gestational diabetes. This year, Prof. Claire Meek examined it yet again in a secondary analysis of a recently-concluded trial known as the DiGest study. It suggested that the stricter time in pregnancy range was associated with the absence of preeclampsia, a potentially dangerous pregnancy complication, and was also associated with positive gestational diabetes pregnancy outcomes.
The case for using CGM-derived metrics in newborns
A related study, the DiGest Newborn Study, showed CGM may be an alternative technique for the identification of neonatal hypoglycemia. Danielle Jones, a PhD candidate at the U.K.’s University of Cambridge, presented findings that suggested that use of a continuous glucose monitor and time in range metrics may be a useful technique for identifying GDM babies with hypoglycemia.
In a separate presentation, Dr. Kathleen Page of USC’s Keck School of Medicine discussed results of her lab’s BrainChild study. The study, which followed children whose mothers had GDM during pregnancy, found that abnormally high blood sugars in the womb appear to affect child brain development and metabolic health.
Growing use of AID during and before pregnancy
An increasing body of work has supported the use of automated insulin delivery (AID), and this includes in pregnancy.
Last fall, Prof. Helen Murphy of the U.K.’s University of East Anglia presented full results of a noteworthy study, AiDAPT, which found that the CamAPS FX AID system improved both outcomes for type 1 diabetes pregnant mothers and their babies.
In May of 2024, the FDA officially cleared the use of the CamDiab’s CamAPS FX algorithm in pregnancy, making the CamAPS FX the first ever automated insulin delivery system approved by the FDA during pregnancy.
New poster data at this year’s ADA continued to support the use of AID in type 1 and pregnancy; research on AID systems for gestational diabetes is still needed. While it was specific to type 1 women who were pregnant or trying to conceive, one data set demonstrated a 2.4 hour per day improvement in time in range among people who were either pregnant or trying to conceive.
Read more about pregnancy and diabetes: