General Medical Information

Examination Techniques in Evaluation of Prepubertal Female Genitalia

Andrew S. Cook

Explanation to both the mother and child of the examination process and the instruments (if any) used is an important precursor to the genital examination. The perception that the virginal introitus is completely covered by the hymen is not uncommon. Newborn hymenal configurations include annular hymen with a central or ventrally displaced orifice (80%), fimbriated hymen (19%), and a septated or cribriform hymen (1%).

Reassurance that the examination will not alter the hymen should help to alleviate potential fears and increase the cooperation of both the patient and her mother. A great deal of information about the female genitalia can be gained during the office examination. The goal of the examination is to obtain the necessary information without causing long-term emotional sequelae. In many cases, the necessary information can be obtained in the office without instrumentation. Occasionally the use of general anesthesia will be necessary to perform an adequate examination. Use of the colposcope can provide detailed information not available without magnification. If vaginal instrumentation is necessary, the preferred type of instrument is dependent on the age of the patient. The Cameron-Miller vaginoscope is both financially economical and efficient.

An initial evaluation of hormonally sensitive tissue will provide a guide of the patient’s endocrine status. Stage of breast development, vaginal mucosal maturation index, pattern of hair growth, and apocrine gland activity will provide information as to sex steroid production. In the child, an ovarian cyst or mass will present as an abdominal rather than pelvic mass, underscoring the importance of a good abdominal examination. The inguinal areas should be examined for the presence of an inguinal hernia or gonad. An inguinal gonad may represent the undescended testes of an undiagnosed male pseudohermaphrodite.

A prepubertal gynecologic examination should include evaluation of the external genitalia, including the clitoris, labia, perineal body and hymen, vagina, and cervix. A rectoabdominal examination or sonographic evaluation may determine the presence and size of the uterus. The normal values and findings of prepubertal female genitalia will be detailed subsequently.

Three different methods used in examination of the prepubertal female genitalia have been compared. Initially 172 children were each examined colposcopically using all three techniques. The examination techniques included (a) the supine position with labial separation, (b) the supine position with labial traction, and (c) the knee-chest position. Each technique was evaluated for the ability to open the vaginal introitus.

For examination in the supine position, the child is placed in a frog-leg position, with her legs abducted and the soles of her feet together. The supine separation method involves the examiner separating the labia with the fingertips in a lateral and downward direction until the introitus opens. The lower aspect of the labia majora are grasped between the thumb and index fingers and with gentle traction pulled, outward and slightly upward with the supine traction technique. The knee-chest examination technique uses the knee-chest position, with the child’s chest on the table and knees separated by 6 to 8 inches. The introitus is opened by placing the examiner’s thumbs on the gluteus maximus at the level of the introitus and lifting, moving the perineal body and posterior fourchette dorsally.

The ability of the three examination techniques to open the introitus was compared. The knee-chest and supine traction techniques (98% and 96%) were superior to the supine separation technique (86%) in the overall ability to open the vaginal introitus. The difference in the ability to open the introitus was especially marked in the younger children. The separation technique opened the introitus in only 29% of infants and 76% of preschoolers. The knee-chest examination method is most successful in opening the vaginal orifice and providing visualization of the cervix but requires an increased level of cooperation from the child. The vertical transhymenal diameters obtained with the knee-chest technique were consistently greater than with the other two techniques.