Hysterosalpingographic diagnosis of a single cervical ectopic ureter.

Single ectopic ureters terminating in the female genital tract are rare congenital anomalies caused by an abnormally lateral origin of the ureteric bud from the mesonephric duct in the three- to four-week embryo. The ureter remains intimately involved with mesonephric duct remnants, which acquire a communication with müllerian structures. Hysterosalpingography in a continent infertile patient outlined a single cervical ureter from a hypoplastic kidney draining into Gartner's duct remnants. No previous case of single cervical ectopic ureter has been reported without a müllerian anomaly, nor has a single cervical ureter been demonstrated on hysterosalpingography.