Assessment of fetal lung maturity by estimation of amniotic fluid palmitic acid.

The measurement of palmitic acid in amniotic fluid has been shown to be a rapid means of assessing the lecithin concentration. The level of palmitic acid increases quickly when the fetal lung matures at about 35 weeks' gestation, and the level in amniotic fluid obtained 24 hours or less before delivery clearly distinguishes which infants are likely to develop respiratory distress syndrome and which are mature.