Comparative study between lamellar body counts and shake test for detection of fetal lung maturity

ABSTRACT

This study was designed to quantify the amniotic fluid lamellar body counts during the third trimester of pregnancy and compare this count with the bubble stability test in prediction of fetal lung maturity and occurrence of respiratory distress syndrome [RDS]. The study was conducted on 25 pregnant women attending Ain Shams University Maternity Hospital. The patients were in the third trimester and the gestational age ranged from 30 to 37 weeks.The gestational age was determined by the date of the last menstrual period and serial ultrasonography. New born Dubowitz assessment was also performed. Amniotic fluid samples were collected either by ultrasound guided amniocentesis or at the time of caesarean section. The present study showed that the choice of 30,000 particles/ul as a decision threshold for lamellar body counts gives the best prediction of respiratory distress syndrome. The sensitivity and specificity of lamellar body counting were 100%. It is more accurate in prediction of RDS than bubble stability test which have a sensitivity of 77.7% and a specificity of 93.4% at cut off point 2 test tubes positive bubble stability test. The present study showed a highly significant relation between lamellar body counts and bubble stability test, gestational age and birth weight. There was also a linear correlation between lamellar body counts and Apgar score at one and five minutes