Abnormal sexual differentiation used to be called hermaphroditism, including true hermaphroditism, male pseudohermaphroditism, female pseudohermaphroditism, Turner’s syndrome, and anorchidism syndrome. I. What is true hermaphroditism? True hermaphroditism is a rare condition in which there are two different gonads (ovaries and testes) in an individual. There are several different cases: 1. one side is testis and the other is ovary or oviduct; 2. one side is ovary and the other is oviduct; 3. both sides are oviduct. There is an infantile uterus in the pelvis. Sex chromosomes were 80% positive. The karyotype is 60% 46,XX, 20% as 46,XY, and the others are 45XO or 46,XX/XY chimeric. H-Y antigen is positive. Serum female hormones are cyclically elevated, consistent with changes in the female menstrual cycle. The external genitalia of these patients are phenotypically different due to different hormone levels in the body. The goal of treatment is to have a suitable sex for social life and then to have children. Therefore, it is necessary to decide the sex of the child at an early age according to the appearance, parents’ requirements, the psychology of the child, and the approval of the society itself, and to remove the gonads of the opposite sex in the body, regardless of the sex, and the oviduct must be removed. In male pseudohermaphroditism, the patient has Y chromosome, and the internal genitalia are a single incompletely developed testis, with different degrees of external genitalia feminization. According to the degree of external genitalia hermaphroditism, there are 2 types: 1. Male external genitalia type The development of penis is close to normal, with male body shape and severe type of hypospadias; there is often cryptorchidism or inguinal hernia, and very few may have vaginal vestiges or infantile uterus and fallopian tubes, but no ovaries. The cause is the failure of the male fetus to inhibit the development of the paramedian tube during embryonic life, resulting in the formation of an underdeveloped uterus and fallopian tubes. This type is also known as paramedian tubular storage syndrome. This type of pediatric patient is usually treated as hypospadias, both repairing the urethra. 2. The female external genital type is also known as complete testis, feminine, with a karyotype of 46, XY. There are testes, normal testosterone biosynthesis, and normal levels of testosterone concentration in the blood. The testes may be in the abdominal cavity, labia majora or inguinal hernia sac. Epididymis and vas deferens may be present at the same time, and some patients are missing. The external genitalia are completely female in shape, with poorly developed penis resembling the clitoris, labia and pseudovagina, but without ovaries, fallopian tubes and uterus. The lesion is due to the complete lack of androgen receptor adhesion protein in the cells of the sexual organs of the patient during the embryonic stage, so that the urogenital sinuses and the external genital progenitor develop into female external genitalia from an early age. In adolescence, normal female breasts and body shape may develop. However, there is no menstrual flow. Since the external genitalia are completely female, parents usually raise the child as a girl at birth and diagnose it only when the testicles are found in the hospital during growth. This type of children cannot grow male organs, so they are not suitable to be male, and the suitable sex is female, and later they need to remove testicles and take estrogen replacement therapy for life. Patients with female pseudohermaphroditism have positive chromatin, karyotype 46,XX, ovaries, fallopian tubes and uterus in vivo, but have external genital malformations and masculine manifestations of shape and precociousness. Both congenital adrenocortical hyperplasia and adrenocortical tumors can secrete excessive androgens, or the administration of male hormonal drugs by the pregnant mother can differentiate the primordial genital ducts and external genital progenitors in the male direction during embryonic life. Congenital adrenocortical hyperplasia is an autosomal invisible genetic disorder in which a congenital defect in one or more enzymes in the synthesis of corticosteroids causes an increase in the secretion of adrenocorticotropic hormones and an increase in the precursors of various cortisols. The patient’s external genital deformity is characterized by an enlarged clitoris, fusion of the labia majora in the shape of a split scrotum, and a common opening between the vagina and urethra, with a residual funnel-shaped urogenital sinus. Masculinity is manifested by rapid growth and epiphyseal age prematurity; early appearance of pubic hair. The hair in the armpit and beard, enlargement of the laryngeal nodes, and thickening of the voice; the breasts do not develop. There is no menstruation and the clitoris can be erect. In addition, a few patients may develop hypertension. This type is best treated with surgery, including clitoroplasty and vaginoplasty, before the age of 3.5 years. And lifelong corticosteroids.