Monitoring placental metabolism is of particular interest for the early-detection of complications during pregnancy. This study discusses the use of dynamic nuclear polarization (DNP) enhanced 13C MRSI of hyperpolarized pyruvate, that has been injected into pregnant rats. The enzymatic conversion of pyruvate to lactate was followed in real-time in maternal and fetal compartments –including placentas. Lactate 13C signals in placentas could be observed; they peaked significantly later and were longer-lived than both placental 13C pyruvate and 13C signals in maternal organs. Single-voxel analyses for both metabolites in different organs revealed the T1 relaxation times and kinetics of the Pyr -> Lac transformation.