However, developmental embryology, as well as the existence of intersexuals, proves this to be a cultural construction. The sex chromosomes determine the differentiation of the gonads into ovaries, testes, ovo-testes, or nonfunctioning streaks. Intersexual genitals may look nearly female, with a large clitoris, or with some degree of posterior labial fusion. They may look nearly male, with a small penis, or with hypospadias.
Some individuals have partial androgen insensitivity.
In an individual with complete AIS and karyotype 46 XY, testes develop during gestation. As in typical male fetuses, the MIH causes the fetal mullerian ducts to regress, so the fetus lacks uterus, fallopian tubes, and cervix plus upper part of vagina. The newborn AIS infant has genitals of normal female appearance, undescended or partially descended testes, and usually a short vagina with no cervix. Occasionally the vagina is nearly absent. AIS individuals are clearly women.