Pseudohermaphroditism In individuals with pseudohermaphroditism, the genetic gender indicates one gender, whereas the external genitalia have characteristics of the other gender. Males with pseudohermaphroditism are genetic males with feminized external genitalia, most commonly manifesting as hypospadias (urethral opening on the ventral surface of the penis) or incomplete fusion of the urogenital or labioscrotal folds. Females with pseudohermaphroditism are genetic females with virilized external genitalia, including clitoral hypertrophy and some degree of fusion of the urogenital or labioscrotal folds. Both types of pseudohermaphroditism are caused either by abnormal levels of sex hormones or abnormalities in the sex hormone receptors.
Another major category of genital tract abnormalities involves various types of uterovaginal malformations, which occur in 0.16% of women (Fig. 5.13) (26). These malformations are believed to result from one or more of the following situations: 1.
Improper fusion of the paramesonephric ducts.
2.
Incomplete development of one paramesonephric duct.
3.
Failure of part of the paramesonephric duct on one or both sides to develop.
4.
Absent or incomplete canalization of the vaginal plate.
Figure 5.13 Types of congenital abnormalities. A: Double uterus (uterus didelphys) and double vagina. B: Double uterus with single vagina. C: Bicornuate uterus. D: Bicornuate uterus with a rudimentary left horn. E: Septate uterus. F: Unicornuate uterus.
Vagina A sagittal section of the female pelvis is presented in Fig. 5.14.
The vagina is a hollow fibromuscular tube extending from the vulvar vestibule to the uterus.
In the dorsal lithotomy position, the vagina is directed posteriorly toward the sacrum, but its axis is almost horizontal in the upright position. It is attached at its upper end to the uterus just above the cervix. The spaces between the cervix and vagina are known as the anterior, posterior, and lateral vaginal fornices. Because the vagina is attached at a higher point posteriorly than anteriorly, the posterior vaginal wall is about 3 cm longer than the anterior wall.
The posterior vaginal fornix is separated from the posterior cul-de-sac and peritoneal cavity by the vaginal wall and peritoneum. This proximity is clinically useful, both diagnostically and therapeutically. Culdocentesis, a technique in which a needle is inserted just posterior to the cervix through the vaginal wall into the peritoneal cavity, is used to evaluate intraperitoneal hemorrhage (e.g., ruptured ectopic pregnancy, hemorrhagic corpus luteum, other intraabdominal bleeding), pus (e.g., pelvic inﬂammatory disease, ruptured intra-abdominal abscess), or other intra-abdominal ﬂuid (e.g., ascites). Incision into the peritoneal cavity from this location in the vagina, known as a posterior colpotomy, can be used as an adjunct to laparoscopic excision of adnexal masses, with removal of the mass intact through the posterior vagina.
Figure 5.14 The pelvic viscera. A sagittal section of the female pelvis with the pelvic viscera and their relationships.
The vagina is attached to the lateral pelvic wall with endopelvic fascial connections to the arcus tendineus (white line), which extends from the pubic bone to the ischial spine.
This connection converts the vaginal lumen into a transverse slit with the anterior and posterior walls in apposition; the lateral space where the two walls meet is the vaginal sulcus. Lateral detachments of the vagina are recognized in some cystocele formations (lateral cystoceles or paravaginal defects).