Testing & Diagnosis for Mixed Gonadal Dysgenesis in Children


The first step in treating a child with mixed gonadal dysgenesis (MGD) is forming an accurate diagnosis. A baby can be diagnosed with MGD soon after birth, when a through physical examination and a series of tests are performed.

How can doctors tell if my child has MGD?

MGD is diagnosed based on the presence of the two abnormal gonads: the undescended testis on one side and the streak gonad on the other. During a physical exam, a physician is only able to feel the testis because the streak gonad isn’t something that can be felt.

If doctors suspect MGD on the initial newborn exam, pediatric specialists in urology and endocrinology will examine your baby right away.

These tests may include:

  • Pelvic ultrasounds to look for female reproductive structures, such as fallopian tubes and a uterus.
  • Blood tests to determine the level of sex hormones in the blood.
  • Gonadal biopsy to assist in gender assignment
  • Karyotyping, a type of analysis that allows doctors to determine the genetic sex of the baby.
  • Genitogram, a type of test that allows doctors to visualize the outline of the reproductive structures.

Can MGD be detected prenatally?

No, MGD is extremely difficult to detect prenatally. Amniocentesis, a procedure doctors use to identify chromosomal disorders in fetuses, isn’t able to accurately detect MGD. This is because a person can have the mosaic 45 XO karyotype involved in MGD and still look normal. A diagnosis of MGD is made based on the presence of the two abnormal gonads, which don’t necessarily result from having the mosaic karyotype.