Lactate detection in the brain of growth-restricted fetuses with magnetic resonance spectroscopy

OBJECTIVE: The objective of the study was to determine the feasibility of detecting fetal brain lactate, a marker of fetal metabolic acidemia, using a noninvasive technique, proton magnetic resonance spectroscopy (H-1 MRS), in intrauterine growth-restricted (IUGR) fetuses. STUDY DESIGN: In vivo human fetal brain lactate detection was determined by H-1 MRS in 5 fetuses with IUGR. Oxygenation and acid-base balance data were obtained at birth. RESULTS: H-1 MRS analysis showed the presence of a lactate peak in the brain of the most severely affected IUGR fetus, with abnormal umbilical artery Doppler and fetal heart rate tracing. This finding was consistent with the low oxygen content and high lactic acid concentration observed in umbilical blood obtained at delivery. CONCLUSION: H-1 MRS allows the noninvasive detection of cerebral lactate in IUGR fetuses. Lactate detected by H-1 MRS may represent a possible marker of in utero cerebral injury or underperfusion.