The earlier tests, Nahum said, allow women at highest risk for gestational diabetes to be identified and treated earlier, possibly heading off complications in both mother and baby. He is lead author of a study on the findings that appears in the August 2002 issue of the Journal of Reproductive Medicine.
Obstetricians have usually screened women in their third trimester because most doctors believe that screening later in pregnancy is more accurate. However, he said, "Screening at 16 weeks is a better predictor of gestational diabetes. It's more sensitive than screening later, and allows us to focus earlier on women who are at greatest risk. It's also a more practical screening technique because blood samples drawn during early pregnancy for other tests can also be used for this purpose."
Nahum and colleagues from the University of Hawaii School of Medicine and California State University studied 255 pregnant women who visited a private obstetrics practice in Honolulu.
All of the women were given a glucose screening test between 14 and 18 weeks of pregnancy. At initial screening, 14 of the 255 women had blood plasma glucose levels higher than 135 milligrams of glucose per deciliter of blood (mg/dL)and were sent for additional testing to confirm a gestational diabetes diagnosis.
The remaining 241 women were screened again at between 24 and 32 weeks. At either point, if women tested higher than 135 mg/dL, they were sent for additional formal glucose tolerance testing.
"Women who had a 16-week glucose screening test result of less than 110 mg/dL had a 99.4 percent chance of not dev
Contact: Amy Austell
Duke University Medical Center