AFTER FORMATION OF THE UTEROVAGINAL CANAL, the segment of each paramesonephric (m?llerian) duct, which
is cranial to the junction of the inguinal ligament and the urogenital cord, becomes the uterine
(fallopian) tubes
The cranial opening of the paramesonephric duct, which is open to the peritoneal cavity, becomes the
fimbriae of the uterine tube
The uterine tube eventually moves caudally and becomes horizontal
THE MESONEPHRIC (WOLFFIAN) DUCTS REGRESS almost completely, leaving only a short segment connected with
the mesonephric tubes adjacent to the ovary which persists as the epo?phoron or Rosenm?ller's body
Other mesonephric tubules caudal to the ovary form the paroophoron
AFTER THE MESONEPHRIC DUCT REGRESSES, the diaphragmatic ligament is attached directly to the ovary at
its cephalic pole and becomes the suspensory ligament of the ovary
The inguinal ligament, which is also attached to the ovary but at its caudal pole, becomes the proper
ligament of the ovary
THE MESONEPHRIC BODY flattens and atrophies beginning in month 3, and only a vestige persists between
the urogenital and the mesonephric mesenteries. These 3 structures together form the mesosalpinx,
which connects the urogenital cord and the uterine tube to the abdominal wall
The mesovarium is thus attached definitively to the inside of the mesosalpinx and is also continuous
caudally with the mesometrium, forming with it, the broad ligament
The lower portion of the genital tract
TWO REGIONS CAN BE DISTINGUISHED on either side of the openings of the mesonephric and paramesonephric
ducts, in the urogenital sinus
The urinary or cranial region (described with the urinary system)
The genital or caudal region, which in turn, has 2 major parts
The interior or deep vertical portion is the pelvic portion of the urogenital sinus
In the female fetus, its cranial end contains the urethral orifice ventrally, and the termination of
the vaginal epithelial plate dorsally
The pelvic portion of the urogenital sinus becomes less deep, bringing to the surface the urethral orifice
(or urinary meatus) and the hymen
The pelvic portion is finally incorporated with the phallic portion, to form with it the vestibule,
which is surrounded by the external genital organs
The superficial or horizontal portion is the phallic portion of the urogenital sinus
It is bordered by the genital tubercle, cranially; and the urogenital membrane, caudally
After resorption of the membrane in week 9, the phallic portion of the urogenital sinus becomes open
to the exterior
Differentiation of the genital portion of the urogenital sinus in the female follows that of the urogenital
excretory system and begins in month 3, paralleling the formation of the vagina and the external genital
organs