**2.7 Bilateral congenital anorchia**

Congenital anorchia often called as prepubertal castrate or vanishing testis syndrome. It is a condition with one or both testes absent in the otherwise normal male (phenotypically and genotypically) [20]. The prevalence of bilateral congenital anorchia is reported to be 1 in 20,000 and that of unilateral congenital anorchia being 1in 5000 males. Anorchia is a case of absence of testicular tissue, monorchia a condition in which only one testis is absent and polyorchia although exceedingly rare refers to the presence of one or more supernumerary testis.

#### **Figure 2.**

*The hormonal role in reproductive development. https://www.urologynews.uk.com/features/features/post/ male-infertility.*

## **2.8 Hormonal defects**

The reproductive hormone axis of males often called as hypothalamic–pituitary axis keeps three important domains. Hypothalamic, pituitary and testicular glands (gonad axis) [21]. The axis regularly works to provide the optimum concentration of hormones much required for smooth reproductive development of males. **Figure 2** sums up the role of hormones in the reproductive development of human males. Malfunction of this system pave way to infertility. Absence of the normal levels of hormones like GnRH leads to the lack of testosterone and is potent enough to cause a group of disorders like hypogonadotrophic hypogonadism [22]. One of the common examples in this case is Kallman syndrome, linked with impaired sense of smell and immaturity. Another common defect that occurs in the gonadal axis includes the inability of pituitary to produce the required levels of luteinizing hormones and Follicular stimulating Hormone that impairs the stimulation of the testes and has direct bearings on the production of the sperms and testosterone [23].
