menstrual cycle and menstruation

Question 1

17 B Oestradiol

Answer 1

Main oestrogen secreted by ovaries

Broken down into: -> oestrone -> oestriol

Question 2

Oestrone

Answer 2

Following menopause majority of oestrone is produced in peripheral fat

Question 3

Androstenedione

Answer 3

Androgen precursor to oestrone
70% converted in adrenal cortex
30% converted in ovary

Question 4

FSH

Answer 4

Glycoprotein from anterior pituitary in response to GNRH
Levels rise during follicular phase (mild surge same time as LH)
Stimulates growth of 6-12 primary follicles

V high post menopause (no -ve feedback by oestrogen +progesterone)

Question 5

Progesterone

Answer 5

Steroid produced by corpus luteum
Enhances endometrial receptivity
Increase endometrial secretions, thick cervical mucus, contraction of os, RR, Ns excretion, body temperature, reduced bowel motility
Rises following ovulation, max during luteal phase day 15-28
No fertilisation -> levels decline
Conception -> maintenance of corpus luteum by gonadotrophin release from trophoblast

Question 6

Formation of corpus luteum

Answer 6

Ovulation = expulsion of oocyte + cumulus oophorus
Remnants penetrated by capillaries + fibroblasts
Granulosa cells undergo luteinisation -> corpus luteum

Question 7

Primary dysmenorrhoea

Answer 7

Dysmenorrhoea from menarche
Oft no cause found
NSAIDs: mefenamic acid, tranexamic acid,
TENS
COCP, mirena, Progestogens
Severe: laparoscopic uterosacral nerve ablation

Question 8

Secondary dysmenorrhoea

Answer 8

Onset of menorrhoea after menarche
Endometriosis, PID, fibroids, iatrogenic: IUD/cervical stenosis
TENS
NSAIDs: mefenamic acid, tranexamic acid
COCP, Progestogens, mirena
Laparoscopic uterosacral nerve ablation

Question 9

LH

Answer 9

Glycoprotein stimulated by GNRH, released from anterior pituitary

Question 10

Risks of PCOS

Answer 10

Endometrial hyperplasia-> Progestogens
Sleep apnoea
DM
Acne
NO increased risk breast/ ovarian Ca

Question 11

PCOS

Answer 11

2/3
Oligo/amenorrhoea
Poly cystic ovaries on USS
Chem/biochem signs of hyperandrogenism

Question 12

Oestriol

Answer 12

Incr uterine growth
Incr fat deposition
Bone resorption
Endometrial growth stimulation

Question 13

Heavy menstrual bleeding

Answer 13

1st: levonorgestrel releasing IUS
2nd: NSAIDs tranexamic acid -> mefenamic acid (SE: n, v + d)
3rd: vaginal hysterectomy

Question 14

PMS

Answer 14

1st line: SSRIs, bit B6, improved diet, exercise, CBT, COCP