PD55-10 MACROSCOPIC WHOLE-MOUNTS CHARACTERIZING SEXUAL DIFFERENTIATION OF THE HUMAN FETAL UROGENITAL TRACT

Abstract

You have accessJournal of UrologyBladder & Urethra: Anatomy, Physiology & Pharmacology II1 Apr 2018PD55-10 MACROSCOPIC WHOLE-MOUNTS CHARACTERIZING SEXUAL DIFFERENTIATION OF THE HUMAN FETAL UROGENITAL TRACT Joel Shen, Dylan S. Isaacson, Mei Cao, Adriane W. Sinclair, Gerald R. Cunha, and Laurence S. Baskin Joel ShenJoel Shen More articles by this author , Dylan S. IsaacsonDylan S. Isaacson More articles by this author , Mei CaoMei Cao More articles by this author , Adriane W. SinclairAdriane W. Sinclair More articles by this author , Gerald R. CunhaGerald R. Cunha More articles by this author , and Laurence S. BaskinLaurence S. Baskin More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.2630AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES An appreciation of normal development of the male and female human urogenital tracts is required to understand congenital anomalies and their clinical implications. Herein we present macroscopic imaging of human fetal urogenital organs from 8 weeks (indifferent stage) to 21 weeks gestation (well differentiated). METHODS Fetal age of first and second trimester human fetal specimens was determined using heel-toe measurement. Gender was determined by Wolffian and Mullerian duct morphology and PCR for the Y chromosome. Length and width measurements from 3 unique specimens were taken at each time point from 8 to 22 weeks. RESULTS The external genitalia, reproductive tract, and gonads show distinct male and female features. External genitalia sex differentiation begins at 10 weeks and is complete at ~17 weeks. The clitoris is close to the size of the penis but lacks a distal urethra and remains close to the body wall. The male and female bladder grows similar in size during development with the male developing a prostate inferior to the bladder. The vas deferens, shown in the posterior view of the male bladder, inserts into the superior aspect of the prostate, medial to the ureters. In contrast to the male, the female reproductive tract is mostly derived from the midline uterovaginal canal (fused Müllerian ducts) and consists of the uterine tubes joining with the uterine body, the cervix and vagina. Gonad sex differentiation begins at 9 weeks at which the testis develops into an egg shape, while the ovary remains oblong. By ~16 weeks, the ovary surpasses the testis in length. Fetal lobulation of the kidney is first seen at ~12 weeks, and no sexual differences were observed. CONCLUSIONS Macroscopic imaging of the developing human fetus shows sex differences in the penis and clitoris, reproductive tract and gonads. The bladder and kidneys were identical in the sexes. Normal sexual differentiation allows an understanding of disorders of sex development. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e1060-e1061 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Joel Shen More articles by this author Dylan S. Isaacson More articles by this author Mei Cao More articles by this author Adriane W. Sinclair More articles by this author Gerald R. Cunha More articles by this author Laurence S. Baskin More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...