Menstrual Physiology and Dysfunction

Question 1

Phases of the ovarian cycle and uterine cycle?

Answer 1

ovarian: follicular, ovulation, luteal
uterine: menstrual, proliferative, secretory

Question 2

Describe the follicular phase of the ovarian cycle?

Answer 2

Primordial follicles are arrested at prophase 1. FSH from the anterior pituitary stimulates a number of primordial follicles to begin maturation. As they mature granulosa cells increase in size and number and secrete oestrogens which drives the cycle.

Question 3

Describe the ovulation phase of the ovarian cycle?

Answer 3

After about 13 days a dominant follicle develops and increases in size. LH surge leads to ovulation.

Question 4

Describe the luteal phase of the ovarian cycle?

Answer 4

The left behind follicle partially collapses and forms the corpus luteum. The corpus luteum secretes oestrogen and progesterone. If no fertilisation occurs the corpus luteum regresses so progesterone secretion falls, the endometrial lining is shed and the cycle can begin again.

Question 5

Describe what happens after the luteal phase if pregnancy occurs?

Answer 5

If fertilisation occurs HCG production from the trophoblast maintains corpus luteum formation until 10-12 weeks of gestation by which time the placenta will be making sufficient oestrogen and progesterone to support iteself.

Question 6

The menstrual phase of the uterine cycle occurs on days ______ is due to ________ and results in _______

Answer 6

1-3
withdrawal of hormones
shedding of the endometrial lining

Question 7

The proliferative phase of the uterine cycle occurs on days ______ is due to ________ and results in _______

Answer 7

1-14 (begins at menstruation)
oestrogen
growth of the endometrial glands and stroma

Question 8

The secretory phase of the uterine cycle occurs on days ______ is due to ________ and results in _______

Answer 8

16-28
progesterone
glandular secretory activity, decidualisation (changes to cells for preparation of pregnancy) and then endometrial apoptosis causing subsequent menstruation

Question 9

Granulosa cells secrete _______

Answer 9

oestrogens and progesterones

Question 10

Thecal cells are stimulated by _______ to secrete ______

Answer 10

LH to secrete ovarian androgens

Question 11

Which phase of the ovarian cycle causes variation in length of cycle?

Answer 11

follicular phase is variable in length luteal phase is fairly constant at 14 days

Question 12

Explain the endocrinology behind the menstrual cycle?

Answer 12

1) pulses of GnRH at about 2hr intervals stimulates FSH and LH release from the anterior pituitary
2) LH stimulates theca cells to produce androgens
3) FSH stimulates growth of ovarian follicles and associated rise in oestrogen causing reduction in FSH by negative feedback
4) When oestrogen reaches a certain concentration it exerts positive feedback resulting in an increase in FSH and LH surge
5) LH surge causes ovulation and regulates the formation of the corpus luteum which secretes progesterone and oestrogen so FSH and LH fall due to negative feedback on GnRH pulsatility
6) oestrogen initially then progesterone cause endometrial proliferation but if no implanatation the corpus luteum regresses, progesterone falls, menstruation occurs
7) fall in progesterone results in increased GnRH and FSH so cycle can begin again

Question 13

Timing of ovulation can be predicted reasonably accurately by ________

Answer 13

LH surge which usually occurs 34-36 hrs before

Question 14

Define menorrhagia?

Answer 14

prolonged and increased menstrual flow

Question 15

Define metrorrhagia?

Answer 15

regular intermenstrual bleeding

Question 16

Define polymenorrhagia?

Answer 16

increased bleeding and frequent cycle

Question 17

Define polymenorrhoea?

Answer 17

menses occurring at <21 days apart

Question 18

Define menometrorrhagia?

Answer 18

prolonged menses and intermenstrual bleeding

Question 19

Define amenorrhoea?

Answer 19

absence of menstruation of > 6 months (primary = a girl who doesnt have a period by 16 secondary = absence of period in someone who previously had them)

Question 20

Define oligomenorrhoea?

Answer 20

menses at intervals of > 35 days

Question 21

List some local organic causes of menorrhagia?

Answer 21

• fibroids (leiomyoma)
• adenomyosis (endometrial tissue in the myometrium)
• endocervical or endometrial polyp
• cervical eversion
• endometrial hyperplasia
• intrauterine contraceptive device
• pelvic inflammatory disease
• endometriosis
• malignancy of cervix or uterus
• hormone producing tumours
• trauma
• AVM of the endometrium (rare)

Question 22

List some systemic organic causes of menorrhagia?

Answer 22

hypothyroidism, prolactin disorders, adrenal disease, diabetes mellitus, bleeding disorders, PCOS

Question 23

List some complications of pregnancy that can cause menorrhagia?

Answer 23

miscarriage, ectopic pregnancy, gestational trophoblastic disease, post partum haemorrhage

Question 24

Treatment of organic causes of menorrhagia?

Answer 24

treat the underlying condition

Question 25

What is dysfunctional uterine bleeding?

Answer 25

abnormal uterine bleeding with no underlying organic cause, diagnosis of exclusion usually caused by some form of hormonal imbalance

Question 26

Dysfunctional uterine bleeding encompasses _____ % of women with abnormal uterine bleeding

Answer 26

50

Question 27

What are the two types of dysfunctional uterine bleeding? What is more common

Answer 27

anovulatory
ovulatory

anovulatory more common- 85% of all DUB

Question 28

Describe anovulatory DUB?

Answer 28

85% of all DUB, irregular cycle, occurs at extremes of reproductive life, more common in obese women

Question 29

Describe ovulatory DUB?

Answer 29

more common in women aged 35-45yo, regular heavy periods, due to inadequate progesterone production by the corpus luteum (eggs and therefore corpus lute is lower quality in older women so don’t get as good progesterone levels)

Question 30

Investigation of DUB?

Answer 30

FBCS
Cervical smear
TSH
Coagulation screens
Renal function
LFTs
Transvaginal US
Pipelle biopsies

Question 31

List some of the medical management for DUB?

Answer 31

oral progesterones 
COCP
Tranexamic acid
Mefenamic acid
GnRH analogues 
Mirena coil

Question 32

Describe oral progesterone in treatment of DUB?

Answer 32

taken on days 6-26 of the cycle as progesterone stops bleeding then get withdrawal bleeding, this is not contraceptive

Question 33

Describe COCP in treatment of DUB?

Answer 33

makes period lighter and regular, acts as a contraceptive, contraindicated in women with risk factors for thromboembolism, breast cancer, smokers > 35 yrs and obese women

Question 34

Describe tranexamic acid as a treatment of DUB?

Answer 34

antifibrinolytic, causes 50% reduction in HMB

Question 35

Describe mefenamic acid as a treatment of DUB?

Answer 35

is a type of NSAID, it works because the endometrium produces a lot of prostaglandins during menstruation

Question 36

Describe GnRH analogues as a treatment of DUB?

Answer 36

these produce a reversible state of menopause by down regulating FSH and LH, they are very effective but cant be used long term due to risk of osteoporosis

Question 37

Describe the mirena coil as a treatment of DUB?

Answer 37

very effective IUD, should be considered in majority as an alternative to surgery

Question 38

Describe use of hormonal agents vs non hormonal for DUB medical treatment?

Answer 38

most agents are contraceptive or not recommended in pregnancy so would have to stop if wanted to get pregnant
if the patient has a regular cycle may use non hormonal treatment, if irregular use hormonal treatment

Question 39

When is surgery for DUB considered?

Answer 39

if tried both drug treatment and the coil

Question 40

Describe endometrial ablation for DUB?

Answer 40

this is usually considered first
there are much fewer complications, shorter recovery
need smear tests as cervix remains
required combined HRT as microscopic endometrium may be left behind and if no progesterone was given there would be an increased risk of endometrial carcinoma
may get monthly spotting due to small bit left over

Question 41

Describe hysterectomy for DUB?

Answer 41

major operation 
more complications
100% amenorrhoea
if total no cervical smears required
oestrogen only HRT (unless cervix remains)

Question 42

Describe maintaining fertility in medical treatments of DUB vs surgical?

Answer 42

medical maintains fertility (although having to stop taking them)
surgery makes you infertile (with ablation technically can get pregnant but very unsafe so generally they sterilise the women when they do the ablation)