Washington, June 15 : A new study has suggested that testing pregnant women for insulin resistance with a simple blood test may be a new tool for predicting problems during pregnancy.
Insulin resistance is a condition in which the body blocks the effects of the hormone insulin. As a result, glucose, or sugar, builds up in the blood, and diabetes can develop. nsulin resistance lies behind the development of gestational diabetes, diabetes that develops during pregnancy, which increases the risk of pregnancy and birth complications.
Therefore, lead author, Weerapan Khovidhunkit, MD, PhD, of Chulalongkorn University, Bangkok, Thailand, and colleagues set out to determine whether insulin resistance is associated with poor outcomes in pregnant women and newborns.
According to The Hormone Foundation, the public education affiliate of The Endocrine Society, it is standard for pregnant women to get a blood test for gestational diabetes between the 24th and 28th weeks of pregnancy.
This test is known as the glucose challenge test or glucose challenge screening.
If this test result is positive, the woman then has an oral glucose tolerance test (OGTT), in which her blood sugar levels are tested 3 hours after she drinks a glucose drink.
"The OGTT is time-consuming. Also, many women cannot tolerate an OGTT due to nausea and vomiting," Khovidhunkit said.
According to Khovidhunkit, it is possible for women to have high insulin resistance without having gestational diabetes.
He said that a special test of insulin resistance, called HOMA, is not part of standard pregnancy tests, but it is quick and easy. This test relies on a fasting blood test of glucose and insulin levels.
The researchers examined 538 pregnant women who had positive glucose challenge tests and then underwent the OGTT. The researchers also assessed insulin resistance using HOMA.
They tracked pregnancy complications, including preeclampsia, a condition involving high blood pressure; excess amniotic fluid (called polyhydramnios); premature rupture of the membranes, in which the woman's water breaks before she goes into labor; and need for a cesarean section.
The researchers found that even if women did not have gestational diabetes, those who had the highest degree of insulin resistance (above 2.44) had nearly 1.5 times the rate of pregnancy complications than those with the lowest insulin resistance.
According to Khovidhunkit, the most common maternal complication was need for a cesarean section.
Similarly, babies born to women in the group that had the highest degree of insulin resistance had a complication rate at birth 1.75 times higher than babies born to women with the lowest insulin resistance.
The authors reported that the most common newborn complications were macrosomia, an abnormally large size, as well as low blood sugar (hypoglycemia).
"Before we can advise pregnant women to undergo this testing, further studies are needed in other patient populations," Khovidhunkit said
The results will be presented at The Endocrine Society's 90th Annual Meeting in San Francisco.