In human society, there is also an individual who is neither a man nor a woman. Say that you are male and have the characteristics of women; Said she looks like a woman, but in fact she has the characteristics of a man. Medically, these men and women are called "hermaphrodites". There are not a few hermaphrodites. A survey in the United States shows that about 2,600 people are born in the United States every year. Due to the severe social reality, they are only identified as men or women, so they will undergo surgery soon after birth. In the United States, there are five such operations every day on average, so that they can be classified as male or female. People with hermaphroditism can be divided into "true hermaphroditism" and "false hermaphroditism". The distinction between true and false is judged according to the main gonads in the body. "True hermaphroditism" people are on the same person's body, with both male testicles and female ovaries. Both the ovary and testis in the body can have endocrine function, that is, estrogen and androgen exist at the same time in the body, but often one of them is dominant. Most of the external genitalia are of unknown sex, and may be female or male, while the development of secondary sexual characteristics often depends on the dominant hormones. If estrogen is dominant in the body, the secondary sexual characteristics tend to be female. If androgens are dominant, the secondary sexual characteristics tend to be male. This vulva has a smaller penis above the urethra and two separate labia majora below. There is a small mouth between the two labia majora that looks like a vaginal opening, but it is actually a place to urinate. This true hermaphrodite will have both male and female characteristics, full breasts, erect penis, sometimes nocturnal emission and no beard. If as a woman, the vagina is shallow and small, and the uterus is small, so there is no fertility. However, there are also reports that people with reproductive functions have been found. The difference between "pseudohermaphroditism" and "true hermaphroditism" is that this human body actually has only one kind of gonad, either male or female. For male gonads, the appearance of external genitalia is female; The external genitalia of female gonads is male. So there are false hermaphrodites, who look like women but are actually men, or who look like men but are actually women.