Prediction of fetal lung maturity from near-infrared spectra of amniotic fluid.

OBJECTIVE

The aim of this study was to attempt to correlate the quantitative data obtained from the near-infrared (near-IR) spectra of amniotic fluid with the lecithin/sphingomyelin (L/S) ratio determined from thin layer chromatographic analysis on the same samples, in order to establish the feasibility of near-IR spectroscopy as an alternate method for the prediction of fetal lung development.

METHODS

Samples of amniotic fluid were obtained by amniocentesis from 52 patients between the 26th and 41st week of pregnancy. About 350 microliters of amniotic fluid was required to record the near-IR spectrum over the entire spectral range between 400 and 2500 nm using a commercial spectrometer. The L/S ratio was determined independently by thin layer chromatography (TLC) for each sample. For correlating the infrared spectra with the TLC-based L/S ratios, a partial least squares analysis was used.

RESULTS

The L/S ratios predicted from the near-IR spectra of amniotic fluid were highly correlated and in excellent agreement with those determined by TLC (r = 0.91).

CONCLUSION

Near-IR spectroscopy has the potential to become an alternate method to TLC for prediction of fetal pulmonary maturity.