The assessment of metabolites in the human fetal brain in utero could have diagnostic value. We explored the feasibility and potentials of proton magnetic resonance spectroscopy ((1)H MRS) for this purpose.(1)H MRS was successfully performed in the third trimester of pregnancy without using sedation. Signals for inositol, choline, creatine, and N-acetylasparatate (NAA) compounds were detected in MR spectra from single voxels in the brain. Absolute tissue levels of these metabolites resemble values measured in preterm and term babies, especially of relatively more mature brain regions, from which most of the MR spectra have been obtained. Brain maturation between 30 and 41 weeks of gestation was most clearly reflected by increasing levels of the neuronal marker NAA.With proper care for the methodological aspects, antenatal (1)H MRS clearly has the potential to evolve into a clinical tool for assessing a number of key metabolites in the human fetal brain in utero.