Menstruation + Disorders Flashcards
Describe the anatomy of the female reproductive tract
*Refer to Netters/web for further pictures
Explain the physiology of the menstrual cycle
Refer to menstrual cycle lecture notes in SEM4 Repro for further info/understanding
What happens in menstruation itself?
- endometrium develops secondary to ovarian cycle
- oestrogen proliferates endometrium
- progesterone maintains endometrium
- failure of conception
- regression of corpus luteum
- fall in oestrogen and progesterone
- distal ischaemia + vasodilatation leads to tissue breakdown + bleeding
- 36 hours after bleeding, endometrial regeneration begins
What is important to ask about in a menstrual history?
- LMP
- cycle length
- menarche
- regularity
- quantity of blood loss
- associated clots
- duration of menses
- IMB/PCB/PMB
- associated pain (dysmenorrhoea)
What is menopause and when does it happen?
- permanent cessation of menstruation due to loss of ovarian follicular function
- there is a transitional period (perimenopause) from approx 5 years prior to final menstrual period (FMP) up to one year after the FMP
- avg age of menopause = 51
What is premature menopause?
Defined as menopause before age of 40
What are the symptoms of menopause?
- reduced fertility
- menstrual irregularities (shortening -> irregular -> absent)
- vaso-motor -> hot flushes, sweats, palpitations
- oestrogen dependent tissue atrophy -> vaginal dryness
- osteoporosis
Menopause results from diminished ovarian reserve -> reduced primordial follicles lead to lower ovarian function, which results in lower oestrogen levels giving rise to symptoms.
What is primary amenorrhoea?
- failure to start menstruating (by age 16)
- in the presence of normal growth and secondary sexual characteristics
- avg age of menarche in UK = ~12
- needs investigation in:
- 16yr old
- 14yr old with no breast development
What is secondary amenorrhoea?
- when periods stop for >6 months*
- in a woman who has previously menstruated
- other than due to pregnancy
*some sources say 3 months
What is oligomenorrhoea?
- infrequent periods
- with a cycle of >35 days
Primary amenorrhoea can cause great anxiety. In most patients puberty is just late (often familial), and reassurance is all that is needed. In some the cause is structural or genetic.
So what needs to be asked/checked?
- has she got normal external secondary sexual characteristics? if so, are the internal genitalia normal?
- causes can be the same as for secondary amenorrhoea (coming up)
- if she’s not developing normally, examination and karyotyping may reveal Turner’s syndrome or AIS - the aim of treatment is to help the patient to look normal, to function sexually and if possible, to enable her to reproduce if she wishes
What are the 5 categories of causes of oligo-menorrhoea?
- physiological
- hypothalamic
- pituitary
- ovaries
- other
What are physiological causes of oligo-amenorrhoea?
- pre-pubertal
- post-menopausal
- pregnant or lactating
What are the hypothalamic causes of oligo-amenorrhoea?
- primary -> rare, due to congenitally reduced GnRH
-
secondary:
- usually psychological factors/stress
- low body fat/anorexia
- excess exercise (up to 44% of competitive athletes have amenorrhoea)
What are pituitary causes of olig-amenorrhoea?
- hyperprolactinaemia (most common) -> hyperplasia or adenoma suppresses the pituitary and gonads (Rx w/ dopamine agonist eg. bromocryptine)
- hypo- or hyperthyroidism
- severe systemic disease eg renal failure
- rare -> pituitary tumours + necrosis (Sheehan’s syndrome)
What are the ovarian causes of oligo-amenorrhoea?
-
acquired:
- PCOS -> extremely common, usually causes oligomenorrhoea
- premature menopause -> 1 in 100
- tumours
-
congenital:
- turner’s syndrome (45XO) -> short stature, poor secondary sexual characteristics
- disorders of sexual differentiation
What are some other causes of olig-amenorrhoea not mentioned?
- pregnancy-related
- asherman’s syndrome (uterine adhesions after a D+C)
- post-pill amenorrhoea
What are relevant investigations for oligo-amenorrhoea?
- b-hCG urine dip -> exclude pregnancy
- assess ovarian + pituitary function -> FSH + oestradiol
- low E2 w/ high FSH = ovarian
- low E2 w/ low FSH = pituitary or hypothalamic
- prolactin, thyroid function
- serum androgens -> PCOS
- imaging -> USS of vagina and uterus for structural abnormalities