Serial fetal lung volume measurement using three-dimensional ultrasound.

Abstract

To establish reference intervals for fetal lung growth. Longitudinal observational study. Fifty-eight women with initially uncomplicated singleton pregnancies were recruited from the antenatal population of a teaching hospital. Four women were excluded from the final analysis because of complications arising in their pregnancy. Each subject was serially scanned at monthly intervals. At each visit lung volume was measured using an ultrasound-based computerized three-dimensional imaging system. Multilevel models were used to determine conditional and unconditional reference intervals. Reference intervals for fetal lung growth were derived. Fetal lung volume increases in a non-linear way with gestation. Our computerized system has the capacity to be used in conjunction with any standard two-dimensional ultrasound scanner in order to measure volume. Lung volume measurement may be useful in predicting pulmonary hypoplasia.