menstrual cycle and menstruation Flashcards Preview

Toni's Obs and Gynae > menstrual cycle and menstruation > Flashcards

Flashcards in menstrual cycle and menstruation Deck (14):
1

17 B Oestradiol

Main oestrogen secreted by ovaries
Broken down into: -> oestrone -> oestriol

2

Oestrone

Following menopause majority of oestrone is produced in peripheral fat

3

Androstenedione

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

4

FSH

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)

5

Progesterone

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

6

Formation of corpus luteum

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

7

Primary dysmenorrhoea

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

8

Secondary dysmenorrhoea

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

9

LH

Glycoprotein stimulated by GNRH, released from anterior pituitary

10

Risks of PCOS

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

11

PCOS

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

12

Oestriol

Incr uterine growth
Incr fat deposition
Bone resorption
Endometrial growth stimulation

13

Heavy menstrual bleeding

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

14

PMS

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