This problem is like a joke, but in fact, in clinical work, we have encountered many times the problem of unclear gender. For example, my patients: a pair of dragon and phoenix fetuses were born “male unlike male, female unlike female”; another couple’s first child was induced with severe congenital heart malformation, and then a fetus was born prematurely in a natural pregnancy, “the obstetrician and gynecologist thought it was a boy, the pediatrician thought it was a girl, and the patient reported that eventually she did not know what she was giving birth to “Is it a boy? Or a girl?” . Other patients are chronically misdiagnosed and mistreated or raised as the wrong gender. In order to raise the awareness of medical professionals and parents about the gender of the child born, the following is a paragraph summary for your reference: 1. Classification of gender: social gender, phenotypic gender, endocrine hormone gender, gonadal gender, chromosomal gender at five levels. Normal people remain consistent in the above five levels. 2, sex reversal: chromosomal sex and gonadal sex do not agree, that is, 46XY patients with gonads for ovaries can not produce androgens, external genitalia and social phenotype are female; or 46XX patients with gonads for testes, produce androgens, external genitalia and social sex are male. These problems are associated with defects, loss, duplication or haploinsufficiency of genes such as SRY, SOX9, DAX1 and SF1, which play a role in gonadal development. Androgen insensitivity syndrome: new subtypes; complete: female presentation; partial: basic female presentation, hermaphroditism, and basic male presentation; mild: male presentation.