8. Menstrual disorders Flashcards
Define amenorrhoea
absence of menstruation
what are physiological periods of amenorrhoea?
ildhood, during pregnancy, during lactation and after the menopause.
WHat is primary amenorrhoea?
Absence of menstruation by age 16 in the presence of normal secondary sexual characteristics, or 14 years in the absence of other evidence of puberty.
What is secondary amenorrhoea?
absent periods for at least 6 months in a woman who has previously had regular periods
What are 4 causes of primary amenorrhoea and which is most common?
- Turner’s syndrome
- Anatomical causes (most common)
- Complete Androgen Insensitivity Syndrome
- Hypothalamic and pituitary disease
What are 3 different anatomical causes of primary amenorrhoea?
- Imperforate hymen
- transverse vaginal septum
- absent vagina or uterus
What is the hymen?
Thin piece of mucosal tissue that surrounds or partially covers the external vaginal opening
What is imperforate hymen?
•An imperforate hymen is a congenital disorder where a hymen without an opening completely obstructs the vagina. It is caused by a failure of the hymen to perforate during fetal development. It is most often diagnosed in adolescent girls when menstrual blood accumulates in the vagina and sometimes also in the uterus.
How does a transverse vaginal septum form?
Due to improper fusion of the mullerian ducts and the urogential sinus
when is an underlying hormonal or chromosomal cause suspected in primary amenorrhea?
If there are no secondary sexual characteristics with primary amenorrhoea
What is Turner Syndrome and how often does it occur?
45XO, missing X chromosome. 1:2500 live female births
Why does primary amenorrhoea occur in Turner’s syndrome?
Ovary does not complete its normal development (ovarian dysgenesis)
No oestrogen = no pubertal changes
How do the ovaries appear on examination?
“streak” ovaries/gonads
What would be the typical lab values of a patient with turner’s syndrome?
- Low estradiol
* High FSH and LH
What other symptoms of Turner’s syndrome are seen as a result of ovarian dysgenesis?
No secondary pubertal changes:
- short stature
- poor breast development
- no pubic hair
Other than amenorrhoea, what will patients with anatomical causes also present with and why?
Cyclical pain due to blood pooling in the uterus or upper vagina every month
What is Complete Androgen Insensitivity Syndrome?
• X-linked recessive disorder
• Resistant to testosterone due to a defect in
the androgen receptor
What would be an individuals genotype and phenotype in CAIS?
46XY but normal female phenotype (female externally)
- insensitive to testosterone so oestrogen causes female characteristics
Why would a person with CAIS have primary amenorrhoea?
Absence of upper vagina, uterus and fallopian tubes. The gonads would be testes, which may be palpable in the labia or inguinal area (surgically removed post puberty)
What hypothalamic/pituitary disorder can cause primary amenorrhoea?
Isolated GnRH deficiency (“Idiopathic hypogonadotrophic hypogonadism”)
• Autosomal dominant or x-linked autosomal
recessive
What does GnRH deficiency also result in?
Poor development of secondary sexual characteristics
What is isolated GnRH deficiency with anosmia called?
Kallman syndrome
What is the diagnosis of GnRH deficiency for primary amenorrhoea?
Constitutional delay of puberty - all aspects of puberty delayed
What are 4 possible causes of secondary amenorrhoea?
- Anatomical causes
- PCOS
- Endocrine
- Hypothalamic and pituitary
What are 2 anatomical causes of secondary amenorrhoea?
Scarring and ovarian disorders
What type of scarring can cause secondary amenorrhoea?
- Cervical stenosis
* Asherman syndrome (intrauterine adhesions)
What are Asherman syndrome and what can cause it?
Intrauterine adhesions (scarring) due to repeated surgeries or instrumentation of the uterus or even repeated infections
What ovarian disorder can cause secondary amenorrhoea?
Primary ovarian insufficiency (POI) - “Premature menopause”
What is primary ovarian insufficiency, what hormone levels would you expect?
Depletion of oocytes before age 40,
• No oestrogen, no inhibin = High FSH (loss of negative
feedback)
What is PCOS and what percent does it contribute to amenorrhoea and oligomenorrhoea?
Polycystic ovarian syndrome
- 20% of amenorrhoea
- 50% of oligomenorrhoea
What the is triad associated with PCOS?
Menstrual irregularity, Androgen excess, obesity
What results from androgen excess in PCOS?
Hirsutism (male pattern hair growth in women), acne
Which hormone is elevated in PCOS?
Elevated LH, causes imbalance of other hormones as well leading to problems with ovulation.