Normal Development of the Penis and Urethra

Abstract

The embryology of the penis and urogenital region remains controversial. This is due to several factors including extrapolation of animal studies to the human, considerable differences in length or age of the embryos at the same developmental stage among different authors, and different terminologies used by different authors. The description in this chapter is based on the available description of the embryological development of the human penis and urethra, the histochemical study of 15 human embryos and fetuses, and the clinical and operative findings of more than 8000 patients with hypospadias. The chapter starts by describing the developmental process, supported by intrauterine photos and histological sections. Review of literature and current theories of urethral development are discussed in Sect. 3.3. The “migration hypothesis” is described in detail to explain the development of the human penis and urethra.