Three-dimensional Ultrasound Estimation of Fetal Adrenal gland Enlargement Compared to Assessment of Cervical Changes Alone &Prediction of Impending Preterm birth

Abstract

Summary P retermlabourcontinuestobeamajorpublic healthproblemwithlast¬ingfamily andsocietalrepercussions. Despitetremendousresearcheffort, preventionstrategieshavefailed,andtheprevalenceofpretermbirthintheUnitedStatesreached 12.3% in 2003. In this study, fetal adrenal gland volume and fetal zone enlargement were used as predictors of preterm birth in comparisonwithcervicallengthmeasurementalone. This study was carried out in Ain Shams University Maternity Hospital, oversix months starting from August 2014tillJanuary2015. This study included seventy-eight pregnant women presented to the Maternity Hospital Emergency Room with signs and symptoms of threatened preterm labour according tothepreviouslyapproved inclusion and exclusion criteria. Each eligible women had undergone full history taking, general examination, local examination, fetal ultrasound biometry, cervical length measurement, and fetal adrenal gland acquisitions. Afterwards, all the enrolled patients had been followed up till delivery, and according to delivery interval from the day of enrollment, patients were categorized into two groups forstatisticalanalysispurposes. The first group (n=36) represented the patients that delivered within 7 days of enrollment into the study, and the second group (n=42) represented patients delivered after 7 daysofenrollment. A cervical length of ≤ 20mm was significantly associated with preterm delivery within 7 days of enrollment with sensitivity 77.8%, specificity 59.5%, positive predictive value (PPV) 62.2%, and negative predictivevalue(NPV) 75.8%. A corrected fetal adrenal gland volume (cAGV) of > 345.3 mm3/kg was significantly associated with preterm delivery within 7 days of enrollment with sensitivity 100%, specificity 100%, positive predictive value (PPV) 100%, andnegativepredictivevalue (NPV) 100%. A fetal zone enlargement (FZE) of > 43.16% was significantly associated with preterm delivery within 7 days of enrollment with sensitivity 100%, specificity 97.6%, positive predictive value (PPV) 97.3%, and negative predictivevalue(NPV) 100%. Statistical analysis of the collected data concluded that fetal adrenal gland volume is the perfect predictor of preterm birth in patients with threatened preterm labour within 7 days of ultrasound scan, followed by fetal zone enlargement, and the cervical length was the least significantpredictorcomparedtotheother twovariables.