The anatomy of the caudal vas deferens in patients with a genital anomaly

We propose that testosterone and Müllerian-inhibiting substance/anti-Müllerian hormone reach the Wolffian and Müllerian ducts by exocrine passage through the Wolffian duct. Thus, where the gonad is a dysgenetic testis the ipsilateral Wolffian duct will be preserved in proportion to the amount of testosterone available. Where a fetus has adequate exocrine secretion of androgen down the Wolffian duct, but inadequate endocrine blood levels of androgen, the vas deferens and vagina can coexist, with incorporation of the vas into the wall of the vagina.