Advances in fetal cardiovascular MRI have been limited by the absence of a reliable cardiac gating signal. Recently, metric optimized gating (MOG) has been proposed as a solution to this limitation. In this thesis, I have developed and validated MOG for cine imaging of the fetal heart. ECG gated cine MR data of the adult heart were acquired from a healthy volunteer to compare MOG reconstructions to conventional ECG reconstructions. The image quality of ECG and MOG reconstructions was compared as was the difference between MOG and ECG trigger times. Fetal images were also acquired, their quality evaluated by experienced radiologists, and the theoretical error in the MOG trigger times calculated. Excellent agreement between ECG and MOG reconstructions was observed. Using MOG, the world’s first gated MR images of the human fetal heart were obtained. Small moving structures were visualized during radial contraction, thus capturing normal fetal cardiac wall motion.