In identifying women with symptoms of preterm labor (PTL) that are at risk for preterm birth within days, a 2D measurement of the fetal zone of the adrenal gland was found to perform significantly better than the commonly used cervical length measurement, according to a study that will be presented today at the Society for Maternal-Fetal Medicine's (SMFM) annual meeting in Chicago.
Ozhan Turan, MD, and colleagues from the University of Maryland at Baltimore and Yale University in New Haven, Conn., designed this study based on a previous study they conducted utilizing 3D ultrasound methods. The prior study, the researchers reported, confirmed 3D adrenal gland volume is a very accurate predictor of preterm birth.
“Most people around the world don't have access to [3D] technology, therefore, we have created measurements that can be done with 2D ultrasound that are very effective to predict preterm birth," explained Turan.
The researchers included 62 women, each presenting with a singelton pregnancy and PTL symptoms between 23 to 37 weeks gestation. Each woman underwent both an ultrasound cervical length measurement and fetal adrenal gland dimension.
Using 3D ultrasound, 2D depth of the whole-gland and fetal zone dimension were measured and Turan and colleagues compared cervical length measurements to adrenal gland measurement of the fetal zone for prediction of preterm birth within seven days of the original assessment.
The researchers found that 20 women delivered preterm at less than seven days following the initial assessment and 42 women experienced preterm birth at the seven-day mark or more. While fetal adrenal gland measurement in predicting preterm birth was noted as more significant within the first group of women, this method was proven more effective than cervical length measurement in both groups of women.
"Prior to this we haven't had a good method to predict who will present with PTL." said Turan. "Measuring the cervical length leads to a high percentage of false positives and also it has limited sensitivity. Hopefully, if adopted, this method will allow for an easy, inexpensive way to identify real pre-term deliveries. Therefore, we will be better managing these pregnancies."