Infrequent Or Absent Periods Flashcards
What does oligomenorrhoea mean?
Infrequent periods
With intervals between menstrual cycles of more than 35 days but less than 6 months
What is amenorrhoea?
Absence of menstrual periods
What is primary amenorrhoea?
Failure to commence menses - no menarche by 16
What is secondary amenorrhoea?
Absent periods for at least 3/12 if previously regular
Absent periods for at least 6/12 if previously oligomenorrhoea
What needs to be functioning to achieve regular menstrual cycles?
All functions of the hypothalamus- pituitary - ovarian axis
What causes oligomenorrhoea?
Constitutional - long cycle then period every 2 weeks and no pathology on investigation
Anovulation - PCOS, thyroid disease, prolactinoma, CAH
Contraceptive/ hormonal treatment
Perimenopause
Eating disorders / excessive exercise
Medications - anti psychotics, AEDs
What causes amenorrhoea?
Physiological - prepubertal, pregnancy, menopause Crytomenorrhoea Uterine/ endometrial causes Ovarian causes Pituitary causes Hypothalamic causes
Why can disease of the hypothalamus cause amenorrhoea?
They can reduce the secretion of GnRH in turn decreasing the pulsatile release of LH and FSH from anterior pituitary, causing anovulation
What can cause hypothalamic amenorrhoea?
Functional disorders - eating disorders, exercise - suppress GnRH production
Severe chronic conditions - psychiatric disorders, thyroid disease, sarcoidosis
Kallmann syndrome - an x linked recessive disorder characterised by failure of migration of GnRH cells
What can cause pituitary amenorrhoea?
Prolactinomas - tumours that secrete high levels of prolactin, which suppresses GnRH secretion
Other pituitary tumours
Sheehan’s syndrome
Destruction of pituitary gland - radiation or autoimmune disease
Post contraception amenorrhoea - prolonged use can cause down regulation of pituitary gland (most commonly seen with depo provera)
What is Sheehan’s syndrome?
Post partum pituitary necrosis secondary to massive obstetric haemorrhage
What can cause ovarian amenorrhoea?
PCOS - more commonly causes oligomenorrhoea, but can present with amenorrhoea Turners syndrome (45X0) Premature ovarian failure - primary ovarian insufficiency before 40
What is Turner’s syndrome?
A genetic condition - female is partially or completely missing an X chromosome.
Symptoms: amenorrhoea, failure to develop secondary sexual characteristics and almost universal infertility.
Many other features - short stature, webbed neck…
How can diseases of adrenal gland cause amenorrhoea?
They can affect ovulation
Late onset /mild congenital adrenal hyperplasia
(An autosomal recessive inherited condition, caused by a partial deficiency of 21 hydroxylase - an enzyme required for synthesis of cortisol and aldosterone)
- may present with early development of pubic hair, irregular or absent periods, hirsutism and acne
- high levels of 17- hydroxyprogesterone present in blood
What is crytomenorrhoea?
When menstruation occurs but is not visible due to obstruction of outflow tract
What examples of crytomenorrhoea are there?
Imperforate hymen
Transverse vaginal septum
Absent vagina
What PRIMARY amenorrhoea causes are there?
Delayed puberty Imperforate hymen/ transverse septum Absent vagina Mullerian agenesis - no uterus Gonadal dysgenesis - Turners syndrome PCOS (but less common primary) CAH
What SECONDARY causes of amenorrhoea are there?
Pregnancy - could be primary PCOS Premature menopause Prolactinoma Thyroid disease Cushing’s Eating disorder Exercise induced Severe stress e.g war zone, famine Ashermann’s syndrome - interuterine adhesions Sheehan syndrome
How does Cushing’s syndrome cause amenorrhoea?
High levels of adrenal hormones e.g cortisol and androgens suppress the normal GnRH production, and therefore LH and FSH
If the disorder is of higher order centres e.g hypothalamus or pituitary, how will FSH and ovarian hormones be affected?
FSH low
No significant ovarian stimulation, so low levels of oestrogen and progesterone secretion
If there is ovarian dysfunction, what will the levels of FSH, oestrogen and progesterone be?
FSH high
Oestrogen low
Virtually no progesterone
What baseline investigations should be done?
Pregnancy test TFT Prolactin FSH, LH 17 hydroxyprogesterone (CAH) USS to visualise ovaries and pelvic anatomy
When investigating primary amenorrhoea, if FSH is low what does this suggest?
Constitutional delay Eating disorder Exercise induced Stress (severe) Chronic illness
When investigating primary amenorrhoea, if FSH is high what should be done?
A karyotype
46XX : premature ovarian failure
45XO : Turners syndrome
