Fetal MRI Acquisition and Sequence Development

Eligibility will be determined prior to the scan session by a pre-screening interview conducted either via telephone or in person asking about MR contraindications. Participants will be excluded from study entry or study completion when any of the following exclusion criteria are met at any time of screening or enrollment: * Claustrophobia sufficient to interfere with MRI or render the subject unable to complete an MRI scan * MRI contraindications (e.g., magnetically or mechanically activated implants) * Weight greater than or equal to 300lbs (weight limit of the MRI table) * Non-English speaking * Neurological conditions (i.e. epilepsy, multiple sclerosis, neurodegenerative diseases, memory disorders, brain tumor) * Past incidence of stroke or heart attack * Severe hypertension, blood disorders, advanced diabetes mellitus, or advanced cardiovascular disease * Hospitalization within 6 weeks prior to enrollment * Significant acute and/or chronic medical conditions, current use of medications that indicate the existence of significant medical conditions, and other unspecified reasons that make the subject unsuitable for enrollment at the discretion at the PI and a consulting MD. Pregnant mothers with the following features will be excluded. * Mothers with contraindication to MRI (such as pacemaker, metal in body, exceeding scanner weight or bore diameter limits (550lbs, 70cm)) * Mothers with claustrophobia * Mothers medically unstable for the MRI study