Infant and Toddler Section: Diagnosis, Treatment, and Genital Care of Intersex Conditions

7. What is intersex?

Intersexuality is a sex abnormality caused by abnormal differentiation during embryonic development. It refers to an individual's sex organs exhibiting characteristics of both male and female sexes. Generally, based on inconsistencies in sex chromosomes, chromatin, gonads, and external genitalia, it can be divided into male pseudohermaphroditism, female pseudohermaphroditism, and true hermaphroditism. If a single individual possesses both testes and ovaries, and their external genitalia and secondary sexual characteristics are intermediate between the sexes, it is called true hermaphroditism. If the gonads and external genitalia are inconsistent, it is called pseudohermaphroditism. If the external genitalia resemble those of a woman but the internal genitalia are testes, it is called male pseudohermaphroditism. If the external genitalia resemble those of a man but the internal genitalia are ovaries, it is called female pseudohermaphroditism.

The pathogenesis of intersex conditions mainly includes:

(1) Sex chromosome aberrations: During embryonic development, the differentiation of sex organs into male or female is initially determined by genetic factors. For example, if the karyotype of a newborn individual is 46XX, it will develop into a female; if the karyotype is 46XY, it will develop into a male. This is because the Y chromosome contains the gene that determines the differentiation of the primordial gonads into testes, while the X chromosome lacks this gene. If the number and structure of sex chromosomes are aberrated, it will inevitably lead to disordered sex differentiation.

(2) Abnormal Androgen Secretion During the Embryonic Period: When the primordial gonads differentiate towards the testes under the control of genetic factors, their cortex degenerates, but the medulla develops well. Therefore, the interstitial cells and adrenal cortex both produce a considerable amount of androgens. Due to the action of androgens, the primordial reproductive tract and external genitalia primordia differentiate towards males. The adrenal cortex produces less androgens, and the reproductive tract and external genitalia primordia differentiate towards females. When the genetic sex is male, and androgen deficiency occurs due to certain reasons; or when the genetic sex is female, and androgen excess occurs, the differentiation of the reproductive tract and external genitalia primordia will be disordered.

(3) Other factors: A decrease in the number of primordial germ cells in the embryo can also lead to masculinization of genetically modified females. A decrease in the number of primordial germ cells can cause the development of the primordial gonadal cortex to be hindered, the deep medulla to form testicular components, and its interstitial cells to produce androgens, causing the primordial reproductive ducts and external genitalia primordia to differentiate in a male direction.

**8. What tests are needed to diagnose intersex conditions?**

Intersexuality is a sex abnormality caused by abnormal differentiation during embryonic development. It refers to an individual's sex organs exhibiting characteristics of both male and female sexes. Generally, based on inconsistencies in sex chromosomes, chromatin, gonads, and external genitalia, it can be divided into male pseudohermaphroditism, female pseudohermaphroditism, and true hermaphroditism.

The diagnosis of intersex conditions mainly includes:

(1) Inquire in detail about the medical history whether there are similar patients in the family and whether the mother has a history of taking male hormones during pregnancy.

(2) Symptoms and signs: Observe the patient's physical characteristics, physical development and secondary sexual characteristics; understand the patient's menstrual status and conduct a detailed examination of the external genitalia.

(3) Laboratory examination of chromatin and karyotype analysis; determination of plasma testosterone, 5-α-dihydrotestosterone, serum estradiol, progesterone, luteinizing hormone, 24-hour urinary 17-ketosteroids, pregnanetriol and HY antigen serological examination.

(4) X-ray examination: wrist X-ray, urogenital sinusography, retroperitoneal pneumography, CT scan of adrenal gland size, etc., to further clarify the specific malformation and etiology, so as to guide the next step of treatment.

**9. How is intersex treatment possible?**

Intersexuality is a type of sex abnormality caused by abnormal embryonic development and differentiation. Patients usually seek medical attention for "abnormal appearance of external genitalia." If not treated early, it will have a great psychological impact on both parents and children.

The most important aspect of treating intersex conditions is determining the sex of the child, ideally as early as possible, generally between 2 and 3 years old. Sex determination is crucial and requires a comprehensive consideration of social gender, psychological gender, biological sex, the wishes of the parents and the patient, and the dominance of the external genitalia, reproductive tract, and gonads. It cannot be solely based on biological sex (i.e., chromosome number). Furthermore, the consistency of the patient's long-term gender roles in society, their psychological identification with those roles, and the wishes of the parents and the patient are equally important. Only by considering all these factors can the most appropriate decision be made. Parents must not impose their own wishes on their child. For example, some parents may have traditional ideas about carrying on the family line and insist on having a boy, which will be detrimental to the child's healthy development.

Drug treatment for intersex conditions mainly involves oral hormones; surgical treatment primarily involves external genital reconstruction and gonadal management, including penile reconstruction, penile correction, urethroplasty, vaginoplasty, hypospadias repair, clitoral and labial reconstruction, and urethral meatus widening, among other procedures. The specific surgical approach must be determined based on the patient's specific abnormalities in the external genitalia, reproductive tract, and gonads.

Intersexuality is not a terrible thing; early treatment is crucial for treatment effectiveness and the patient's quality of life. At the same time, after the sex of the child is determined, parents should help the child develop a correct understanding of gender roles.