Ideal 1-hour 50-g glucose challenge test cutoff ≥135 mg/dL, say researchers in the American Journal of Obstetrics & Gynecology
A common complication, gestational diabetes affects approximately 6-7% of pregnant women. Currently, screening is done in two steps to help identify patients most at risk; however, the suggested levels for additional testing were based on singleton pregnancy data.
Now investigators have analyzed data from twin pregnancies and have determined that the optimal first step cutoff for additional screening appears to be a blood sugar level equal to or greater than 135 mg/dL for women carrying twins. Their findings are published in the American Journal of Obstetrics & Gynecology.
Gestational diabetes mellitus (GDM) is believed to be caused by increased levels of human placental lactogen, estrogen, cortisol, prolactin, and progesterone. GDM is linked to several adverse birth outcomes such as preeclampsia, macrosomia, birth injury, and cesarean delivery. Because of the possible negative effects, screening for GDM is an important component of prenatal care.
Representing approximately 3.3% of all live births in the United States, twin pregnancies present unique medical challenges; however, most of the available data regarding GDM testing thresholds are based on singleton pregnancies. Since carrying twins amplifies the normal physical changes that accompany pregnancy, a team of researchers from the Icahn School of Medicine at Mount Sinai and the New York University School of Medicine set out to pinpoint the most effective screening cutoff for women pregnant with twins.
Currently, the American Congress of Obstetricians and Gynecologists advocates a two-step diagnostic approach. Women are screened between 24-28 weeks, using a nonfasting 1-hour 50-g glucose challenge test (GCT). If a patient exceeds the recommended cutoff (between ≥130 mg/dL and ≥140 mg/dL), additional testing is performed to diagnose or rule out GDM.
In this study, doctors analyzed data from 475 women pregnant with twins who were treated at their hospitals between 2005 and 2013. Specifically, they focused on three potential cutoff thresholds for the GCT: ≥130 mg/dL, ≥135 mg/dL, and ≥140 mg/dL. The investigators found that the optimal cutoff for the 1-hour 50-g GCT screening was ≥135 mg/dL. The data revealed that the 130 mg/dL cutoff did not show any additional predictive value, yet increased the test positive rate. The 140 mg/dL cutoff would have failed to identify 6.5% of patients with GDM.
"With the increasing prevalence of twin pregnancies, understanding how to better screen for GDM is important in this population because of the unique circumstances that may put this group at increased risk for development of insulin resistance, as well as their altered physiology, which would limit the ability to extrapolate from data derived from singleton pregnancies," says investigator Nathan S. Fox, MD, Associate Clinical Professor, Obstetrics, Gynecology and Reproductive Science, Icahn School of Medicine at Mount Sinai. "We found that the optimal GCT cutoff appears to be ≥ 135 mg/dL. This cutoff yielded 100% sensitivity with only a 28.6% test positive rate."
While early detection and screening are essential for effective treatment and control of GDM, unnecessary follow-up testing can cause mental stress for the mother and result in additional out-of-pocket expenditures. "As opposed to a cutoff of ≥130 mg/dL, a cutoff of ≥135 mg/dL could potentially decrease cost and anxiety, without decreasing the sensitivity of the test," explains Dr. Fox.
For now, this study represents an important first step in addressing the distinctive differences between GDM in twin and singleton pregnancies, but more research is needed to fully develop guidelines to better serve mothers carrying twins. "There is much more to learn regarding GDM in twin pregnancies that could be addressed with future prospective studies," concludes Dr. Fox. "More research is needed in twin pregnancies to confirm this finding in other populations, as well as to establish the optimal GDM screening and treatment paradigm in twin pregnancies."
Eileen Leahy | EurekAlert!
Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
18.10.2017 | Materials Sciences
18.10.2017 | Physics and Astronomy
18.10.2017 | Physics and Astronomy