Sonographic diagnosis of abnormal fetal genitalia.

Sonographic fetal gender determination is undertaken as part of many prenatal ultrasound examinations. We describe three abnormalities of the fetal phallus, two that were related to family history and one that was associated with other genitourinary tract abnormalities of the fetus. Examination of the fetal genitalia is an important part of the sonographic examination, particularly when there is a genitourinary fetal anomaly or a family history of abnormal genitalia, because the external genitals are a part of the genitourinary tract that can occasionally be malformed. Caution is advisable in the sonographic gender determination in these cases.