Screening and diagnosis

Classification and risk stratification

Perioperative care

Quality improvement

Patient education

Nonpharmacologic interventions

Therapeutic procedures

Respiratory support

Follow-up and surveillance

Specific circumstances

Preventative measures

Medical management

Surgical interventions

Inpatient care

Diagnostic procedures

Diagnostic investigations

Insufficient evidence to make a recommendation.

Strongly favor this test or intervention.

The Prader staging system provides a structured way to assess the degree of virilization in female external genitalia, categorizing them into five distinct stages. This system utilizes a single input, which describes the observed characteristics of the male-appearing genitalia. Each description matches a particular stage on the Prader scale. Here's how the classification works:

- If the finding is "Clitoromegaly, no labial fusion," this is categorized as Stage I. This stage represents the least virilization, where the clitoris is enlarged but there's no fusion of the labia.
  
- "Clitoromegaly, posterior labial fusion" corresponds to Stage II. In this stage, there is a noticeable enlargement of the clitoris along with fusion at the backside of the labia.
  
- Stage III is allocated to "Greater clitoromegaly, near-complete labial fusion, single perineal urogenital orifice." Here, the clitoris is even more enlarged, the labial fusion is almost complete, and a single opening serves both urinary and genital functions.
  
- When the description is "Phallus-like clitoris, complete labial fusion, urogenital sinus at the base of the clitoris," it is classified as Stage IV. The clitoris appears more like a phallus, the labia are fully fused, and the urogenital sinus, a common channel for the urinary and genital tracts, is located at the base of the enlarged clitoris.
  
- Lastly, a "Penile clitoris, scrotum-like labia without palpable testes, urethral meatus at the tip of the phallus" results in Stage V. This stage reflects the most advanced virilization, where the clitoris resembles a small penis, the labia mimic a scrotum, but there are no testes. The urethral opening is positioned at the tip of this phallic structure.

By systematically matching these observations with the established criteria, the Prader staging system allows for clear and precise classification, providing a foundational understanding of the extent of virilization in affected individuals.

The Prader staging system is a clinical calculator used to assess the degree of virilization of the external genitalia in females. This system is primarily used in patients with disorders of sex development (DSD), particularly those with conditions such as congenital adrenal hyperplasia (CAH) or androgen insensitivity syndrome (AIS). 

The Prader staging system ranges from stage 0, which represents typical female genitalia, to stage 5, which represents typical male genitalia. The stages in between describe varying degrees of virilization. 

The clinical utility of this calculator is to provide a standardized method of describing the degree of virilization, which can assist in diagnosis, management decisions, and communication between healthcare providers. It can also be used to monitor the progression of virilization over time.

There are no specific exclusion criteria for the use of the Prader staging system, but it is most relevant in patients with suspected or confirmed DSD. It is not typically used in individuals without these conditions.

Prader staging for virilization of female genitalia

Congenital adrenal hyperplasia

Emergency self-injection kit

Transition to adult care

Management of classic CAH

Management of classic CAH, dose adjustments

As per JES/JSNS/JSPE/JSPU 2022 guidelines, 

General counseling

Prenatal treatment

Management of classic CAH, choice of agent

Medical alert bracelet

Genetic counseling

Genetic testing

Pregnant patients

Gender assignment

Adrenal imaging

Clinical follow-up

Management of classic CAH, initiation of treatment

Complete adrenocortical profile

Management of non-classic CAH

Management of non-classic CAH, discontinuation of treatment

Management of non-classic CAH, initiation of treatment

Indications for surgery

Screening for non-classic CAH

Surveillance for treatment-related complications

Cosyntropin stimulation test

Neonatal screening

Management of non-classic CAH, stress dosing

Clinical assessment

Surveillance for testicular tumor

17-hydroxyprogesterone

Assessment of treatment response

Indications for referral

Psychological support

Congenital adrenal hyperplasia

Guidelines

Key sources