Cholesterol in amniotic fluid, determined by gas chromatography.

Cholesterol was extracted from amniotic fluid, saponified, converted to its trimethylsilyl derivative, and gas chromatographed, with cholesteryl acetate as the internal standard. The method is sufficiently accurate and precise for use with the range of concentrations of cholesterol found in amniotic fluid (5 to 48 mg/litre). Total cholesterol was measured in amniotic fluids collected at different stages of gestation. No significant trend or change was observed nor was cholesterol in the amniotic fluid and the mother's serum correlated at any stage of gestation. Thus we conclude that cholesterol is not a useful indicator of fetal age or maturity. Cholesterol concentrations in amniotic fluid from complicated pregnancies were within the range found for normal pregnancies.