[Ultrasonographic density of amniotic fluid and its correlation with fetal pulmonary maturity]

In order to determine if the amniotic fluid density is correlated with fetal lung maturity, we carried out a prospective study in the Hospital de Gineco-Obstetricia del Centro Médico León del Instituto Mexicano del Seguro Social. One hundred and forty one patients with pregnancies between 13 and 41 gestation weeks were included. The amniotic fluid density was calculated by counting the level of echoes (free-floating particles) in the amniotic fluid. We found a significant correlation (P < 0.05) between the level of echoes and the gestation age, nevertheless, the correlation coefficient was very low (R = 0.28), therefore we concluded that this procedure is not a reliable predictor of fetal lung maturity.