Amenorrhoae and Erectile dysfunction Flashcards
Match the following A.Oligomenorrhoea B. Amenorrhoea C. Primary amenorrhoea D. Secondary amenorrhoea E. Erectile dysfunction
- Failure to begin spontaneous menstruation by 16
- Absene of menstrucation for 3 months in a woman who has previosuly had cycles
- Menstrual cycle length >6 weeks but <6 months
- Inability of the male to achieve or sustain an erection adequate for satisfactory intercourse.
- Complete absence of menstruation or cycle length >6months
A3 B5 C1 D2 E4
What hormones are involved in the female axis?
GnRH, LH, FSH, progesterone, oestrogen
- Ovary end organ
What hormones are involved in the male axis?
GnRH, LH, FSH, testosterone
- Testes end organ
How does the hypothalamus regulate steroid synthesis?
Steroid synthesis is reguated by the kisspeptin neurons
What is the function of kisspeptin neurons?
Act as central processors to relay peripheral signals to GnRH neurons
What secretes kisspeptin?
Kisspeptin is secreted by neurons in discrete hypothalamic nuceli, directly innervating and stimulating GnRH neurons through GPR54 receptors (Kiss1r gene)
What conditions occur in mutations to Kiss1 and Kiss1r?
Profound hypogonadotropic hypogonadism
How does kisspeptin induce GnRH release?
Kisspeptin signals directly to the GnRH neurons through the action on the kisspeptin receptor to release GnRH into the portal circulation.
What is kisspeptins function in development?
Required for normal puberty and reproductive function
How is kisspeptin signalling regulated?
Regulation occurs via metabolic cues where leptin can induce kisspeptin signallin.
There is some regulation via negative feedback.
- Females:high levels of oestrogen and progesterone stimulate the pre-ovulatory stage (increase GnRH and LH). It will also inhibit Kiss1 expression in the arcurate nucleus
- Males: males high testosterone levels suppress GnRH, LH and FSH release, partly via kisspeptin neurons of the ARC.
Describe the hormone levels in the menstrual cycle?
In the follicular phase LH and FSH is low, which gradually rise in the cycle peaking in the middle. E2 pattern is similar to LH. Progesterone rises after ovulation (day 14)
What is amenorrhoea?
Complete absence of menstruation or cycle length >6months
What does the investigation of amenorrhae combine?
Clinical history, clinical examination, laboratory and imaging
What are primary and secondary causes of amenorrhoae associated with?
Primary= ovarian
Secondary=pituitary
What does the clinical evaluation include?
General health, body shape and skeletal abnormalities, weight and height, evidence of virilisation, galactorrhoea, normality of vagina, cervix and uterus
What does the history examination entail?
analysing date of onset, age of menarche, sudden or gradual onset, general health, weight, stress, excessive exercise, drugs, sense of smell, PMH in pregnancies or gynaecological surgery
What are the test for amenorrhoae and when should it be carried out?
- LH, FSH, E2 (follicular ideally day 2-3)
- prolactin
- progesterone on day 21/7days before expected bleed (>30nm/L=ovulation)
- testosterone, adristenedione, DHEAS & SHBG
- 17-OH progesterone (basal + ACTH stimulated)
- TFT
- HCG
- steroid profile
Describe pituitary function tests
GnRH test is used to investigate gonadotrophin deficiency (low LH and FSH)
- 100ug GnRH is administered IV and samples collected at 0, 20, 60min. Expect to see significant rise in LH and FSH
- If LH rise>FSH rise then post-pubertal (vice versa for pre)
Clomifene test a selective oestrogen receptor modulator (SERM) used to distinguish between distinguish gonadotrophin deficiency from weight related hypogonadism.
- 50g of clomifene administered for 5 days
- LH and FSH measured on day 0 and 7
- Expect to see rise above reference range or 2x basal
- Lack of response= LH and FSH deficiency due to a pituitary/hypothalamic disease