Ovary and testicle and everything in between: lesions and imaging in the newborn.

Assessment of the neonatal reproductive tract requires an understanding of embryology, awareness of common clinical presentations, and familiarity with normal newborn variation. This review of the neonatal reproductive tract emphasizes the use of sonography in the evaluation of developmental, acquired, and neoplastic conditions in male and female newborns. Anchored in embryologic origins, the discussion also includes descriptions of findings that may be encountered in prenatal imaging. Comments on clinical correlation are included to guide appropriate triaging of these complex cases. Imaging pearls and pitfalls are incorporated into this review, including the recognized effects of maternal hormones in female infants.