1. Autopsy will be performed at Mount Sinai Hospital according to accepted current standards, based on clinical indications. Macroscopic examination of the fetus will be performed initially, followed by organ removal for tissue fixation for a period of two weeks. The brain is then scanned with MRI at the Hospital for Sick Children. The brain is transported in an air-tight container containing 10% formalin and sealed with paraffin lined tape. All brains will be anonymised and coded with a number prior to MRI examination. Following MR imaging, the tissue will be examined, sampled and reported in the usual fashion at Mount Sinai Hospital.