Here are some examples of being intersexed. Occurring about once in 2500 births, the child typically develops normal female gender identity. She has a higher probability of mental retardation, especially if with more than 3 X-chromosomes. He will typically have small external genitals, female secondary sex characteristics, reduced sex drive, erection problems, gender identity problems, be sterile, and have a greater likelihood of mental retardation. Since an X chromosome is necessary for survival, YO is not viable.
Gonadal Sex is related to having either ovaries or testes.
At about 6 weeks prenatal, testes start producing testosterone. Hormonal sex is the same for the first 6 weeks prenatal. Prenatal hormones influence development of external genitals, depending on the ratio of estrogens to androgens, and brain dimorphism. Pseudo-hermaphrodites have normal gonads of one sex with ambiguous genitals. The latter occur about 1.5 times per 100,000 births.