ANALYSIS OF FETAL AND NEONATAL URINE USING PROTON NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY

.Aim-To use high field proton nuclear magnetic resonance spectroscopy (H-1 NMR) to characterise the low molecular weight metabolite composit ion of neonatal and fetal urine in relation to gestational age and per inatal outcome. Methods-The first urine passed by two neonatal groups, six full term and five preterm infants with normal renal function, wa s analysed by 1H NMR and compared with fetal urine from 14 cases with obstructive uropathy. Results-The mean ratios of taurine, myo-inositol , and trimethylamine-N-oxide (TMAO) to creatinine were 4.3, 10.1, and 14.1 times higher, respectively, in the preterm group when compared wi th those of the full term group. Fetal obstructive uropathy was charac terised by glycosuria, amino and organic aciduria, regardless of gesta tional age (13-30 weeks). Conclusions-Samples of the first urine passe d - that is, urine produced in fetal life - by normal preterm infants are useful controls for cases of obstructive uropathy detected in the third timester. H-1 NMR will become a clinically useful tool for monit oring renal development and abnormalities in utero.