Determination of fetal maturity and of development of the fetal lungs by means of combined methods.

The validity of the assessment of the fetal age and pulmonary maturity was evaluated on 369 patients at various stages of normal pregnancy and complicated by diabetes, toxemia and fetal anencephaly. Gestational maturity was assessed by ultrasonic measurement of the fetal biparietal diameter and by analysing constituents of amniotic fluid (creatinine, bilirubin, fat cells) while pulmonary maturity was assessed from the L/S ratio in the amniotic fluid. Each individual method has a wide margin of error, however, ultrasound cephalometry gave the best prediction for determination of fetal age.