Testicular feminization occurs in a person who is genetically male and has the external appearance of a female.
The male hormone testosterone works by binding to a protein in cells of the body. If there is a defect in this protein, the cells do not respond to testosterone. This is what happens in testicular feminization.
The female hormone is present in both sexes. So someone with testicular feminization will develop on the outside as a female. Inside, there is a vagina, but the upper part of the uterus and the fallopian tubes are missing. There are underdeveloped testicles in the pelvis. Externally, the person looks like a completely normal female.
The complete form of testicular feminization is a genetic defect. No other problems are associated with it. Incomplete forms may happen along with a variety of unusual genetic syndromes.