Clinical Gynecology: Primary Amenorrhea Flashcards
Androgen Insensitivity Syndrome
Epidemiology
- Incidence: 1/60,000
- 9% of primary amenorrhea cases
- Genetics: X-linked recessive
- Genotype: XY
- Phenotype: female
Androgen Insensitivity Syndrome
Pathophysiology
X-linked recessive mutation in androgen receptor
* Testosterone is produced but cannot activate receptor
- Amenorrhea
- Female external genitalia with small vaginal dimple
- Absent uterus & cerviox
- Cryptorchidic gonads
- Absent axillary & pubic hair
- Large breasts with juvenile nipples
- Labs: testosterone in normal to high male range
Clinical Presentation
Androgen Insensitivity Syndrome
Androgen Insensitivity Syndrome
Approach to Therapy
Removal of gonads
* Recommended after completion of pubertal development
* Once removed, treat with HRT
Mullerian Agenesis
Epidemiology
- Incidence: 1/5000
- Normal XX karyotype
Mullerian Agenesis
Pathophysiology
Absence of uterus, cervix, and upper 2/3 of vagina
* Caused by mutations in Antimullerian Hormone or Antimullerian Hormone Receptor
- Amenorrhea
- Normal external genitalia + vaginal dimple
- Normal breast development
- Normal secondary sex characteristics
- Absence of internal midline structures (pelvic exam)
Clinical Presentation
Mullerian Agenesis
Imperforate Hymen
Epidemiology
Most common obstructive lesion of the female genital tract: 1/1000 female births
Bulging, blue-domed, translucent membrane
* Can present with hematocolpos or urinary retention
* Membrane will bulge with valsalva
Clinical Presentation
Imperforate Hymen
Imperforate Hymen
Approach to Therapy
Surgical resection
Failure of canalization of the distal third of vagina
* Most common in upper & middle third of vagina
Transverse Vaginal Septum
Gonadal Dysgenesis
Pathophysiology
Characterized by congenital loss or underdevelopment of germ cells within gonad during organogenesis
* Gonads usually contain only fibrous tissue (streak gonads)
Most common form of gonadal dysgenesis
Etiology
Turner’s Syndrome (45, X)
Turner’s Syndrome
Epidemiology
Incidence: 1/2,000 female live births
Turner’s Syndrome
Pathophysiology
Absence of ovarian determinant genes result in premature loss of germ cells
* 45,X fetuses have same amount of germ cells as 46,XX at midgestation
* As gestation continues, accelerated loss of germ cells occurs in 45,X fetuses
* Many 45,X individuals lose all germ cells prior to birth