CAUSES OF AMENORRHOEA :
DEPENDING ON THE STATUS OF THE SERUM FSH LEVELS
1. HYPERGONADOTROPIC PRIMARY AMENORRHOEA ( FSH > 40 MLU/ML )
* ABNORMAL SEX CHROMOSOMES
- GONADAL DYSGENESIS : 45 OX, TURNER SYNDROME, MOSAICS, ABNORMAL X
* NORMAL SEX CHROMOSOMES :
- 46 XX PURE GONADAL DYSGENESIS
- 46 XY GONADAL DYSGENESIS- SWYER SYNDROME
- GONADOTROPIN-RESISTANT OVARY SYNDROME - SAVAGE SYNDROME
2. EUGONADOTROPIC PRIMARY AMENORRHOEA
* ABSENCE OF MULLERIAN EVELOPMENT
- ANDROGEN INSENSITIVITY SYNDROME ( TESTICULAR FEMINIZATION )
- MULLERIAN AGENESIS - ABSENCE OF UTERUS/ VAGINA
* NORMAL MULLERIAN DEVELOPMENT:
- FEMALE OR TRUE INTERSEX
- POLYCYSTIC OVARIAN SYNDROME
- ADRENAL OR THYROID DISEASES
* CRYPTOMENORRHOEA
- VAGINAL SEPTUM
- IMPERFORATE VAGINA, HYMEN, CERVIX
- ABSENCE OF VAGINA
- DOUBLE UTERUS WITH RETENTION
- HAEMATOCOLPOS
- HAEMATOMETRA
3. HYPOGONADOTROPIC PRIMARY AMENORRHOEA
* HYPOTHALAMIC CAUSES:
- DELAYED MENARCHE
- HYPOTHALAMIC HYPOGONADISM ( KALLMAN SYNDROME )
- PSYCHOGENIC / WEIGHT LOSS
* PITUITARY CAUSES :
- NEOPLASM - PROLACTINOMAS , CRANIOPHARYNGIOMAS
- HYPOPITUITARY STATES: SIMMONDS DISEASE, CHIARI-FROMMEL SYNDROME, FORBES-ALBRIGHT SYNDROME, FROHLICH SYNDROME, LAURENCE-MOON BIEDL SYNDROME
* SEVERE SYSTEMIC DISEASES LIKE TUBERCULOSIS
OTHER TESTS :
* SERUM FSH LEVELS - > 40 MLU/ ML & LOW ESTRADIOL LEVELS ( <25 PG/ML ) -> HYPERGONADOTROPIC PRIMARY AMENORRHOEA
* 200 MG PROGESTERONE IN OIL ( A PROGESTATIONAL AGENT WHICH HAS NO OESTROGEN ACTIVITY) SHOULD BE GIVEN I.M. , OR 10 MG MEDROXYPROGESTERONE ACETATE BY MOUTH FOR 5 DAYS, IF BLEEDING OCCURS WITH 2-7 DAYS OF STOPPING TREATMENT, IT SHOWS THAT THERE IS FUNCTIONAL UTERUS WITH REACTIVE ENDOMETRIUM. THE TEST IS NEGATIVE ( NO BLEEDING ) IN HYPERGONADOTROPIC CASES. IF THERE IS NO GALACTORRHOEA & SERUM PROLACTIN IS NORMAL, NO FURTHER TESTS ARE REQUIRED.
* IF SERUM PROLACTIN IS RAISED WITH GALACTORRHOEA, CT SCAN OF HEAD IS DONE TO SEE SELLA TURSICA FOR EVIDENCE OF PROLACTINOMA.
* IF BLEEDING DOESNT OCCUR AFTER PROGESTERONE INJ. THERE MAY BE ABNORMALITY OF UTERUS OR VAGINA LIKE CONGENITAL ABSENCE , VAGINAL ATRESIA , TESTICULAR FEMINIZATION , ASHERMAN SYNDROME. CONFIRMATION OF THESE CONDITIONS IS OBTAINED BY PRIMING THE ENDOMETRIUM WITH OESTROGEN ( 20 MCG ETHINYL OESTRADIOL DAILY FOR 20 DAYS ) BEFORE ADDING PROGESTERON & NO BLEEDING WILL OCCUR. IF BLEEDING OCCURS WITH EOSTROGEN + PROGESTERONE COMBINATION & NOT WITH PROGESTERONE ALONE, THE FAULT LIES IN THE OVARIES, PITUITARY OR HYPOTHALAMUS.
* SERUM GONADOTROPHINS SHOULD BE MEASURED - A RAISED FSH & LH LEVELS INDICATE OVARIAN FAILURE WITH ABSENT FOLLICLES FROM A PREMATURE MENOPAUSE, TURNER SYNDROME , OTHER FORMS OF OVARIAN DYSGENESIS , OVARIAN AGENESIS ( VERY RARE ) , RESISTANT OVARY SYNDROME
* IF PELVIC ORGANS, PROLACTIN LEVELS , CT SKULL & GONADOTROPHINS ARE NORMAL, THE AMENORRHOEA THEN BEING HYPOTHALAMIC IN ORIGIN WHICH MOST COMMONLY FOLLOWS WEIGHT LOSS OR CONTRACEPTIVE PILLS.
* KARYOTYPING TO SEE CHROMOSOMAL PATTERN.