Association between maternal-fetal Doppler velocimetry and fetal lung maturity.

Aims: To correlate maternal-fetal Doppler velocimetry parameters to indices of fetal lung maturity (FLM). Methods: Fifty-five consecutive third trimester pregnancies in which a pulsed-wave Doppler study, including uterine resistance index (Ut RI), umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI) and the UA/MCA ratio was performed within 24 hours before amniocentesis and within a week from birth. FLM was determined by amniotic fluid lamellar bodies count (LBs). Results: A positive correlation between MCA PI and LBs (p 0.64 was correlated to delayed FLM (LBs < 20,000/μl; sensitivity: 90.9%, specificity: 90.3%; positive predictive value: 76.9%, negative predictive value: 96.6 %). Comment: In third trimester pregnancies abnormal uterine artery waveforms may be associated to a delayed FLM, as expressed by decreased amniotic fluid LBs.