Endometrium Flashcards
What factors are increased during the luteal phase of the menstrual cycle?
[in the endometrium]
- inflammatory cells
- gland hypertrophy
- increased mucus secretion
- spiral artery growth
What are the 4 layers of the endometrium?
- compactum: proliferative layer
- spongiosum: secretory layer
- basalis: layer will remain intact after menstruation
- junctional zone: anchor which sits between basalis layer and the myometrium. Contains properties of both endometrium and muscle. some roles proposed in pregnancy and menstrual problems.
What is mechanism underlying menstruation?
- Caused by withdrawal of E2 and P
- mediated by PGs (which vasoconstriction) and platelet aggregating factor (PAF)
this causes:
- spiral artery vasoconstriction
- spiral artery relaxation
- PGs cause vasoconstriction of end-arteries in the endometrium - there is no alternative blood supply to these areas so this causes ischaemia
- ischaemia and tissue damage
- shedding of functional endometrium
What is the functional endometrium?
these are the layers that are lost during menstruation
=> compactium and spongiosum layers
What are the 2 general types of prostaglandins?
VASOCONSTRICTORY
promote platelets clotting (pro-coagulable)
PG-F2a and PG-Tx
VASODILATORY
reduces platelet binding to the endothelium
(pro-bleeding)
PG-E and PG-I
What are the general functions of prostaglandins?
- inflammatory mediators
- vasodilation
- vasoconstriction
- sensitise pain receptors (all classes of PGs)
What inflammatory mediators are released during menstruation?
- PGs
- IL-8, IL-13, IL-16
- TNF
- PAF
- Matrix metalloproteinases (MMPs)
- coagulation/fibrinolysis
What must occur for “normal menstruation?”
correct balance and regulation of inflammation, coagulation and fibrinolysis in the endometrium
What clinical problems can occur in association with menstruation?
[anything different to usual baseline pattern]
- menorrhagia: excessive bleeding
- polymenorrhoea; bleeding too often
- Inter-Menstrual bleeding (IMB)
- post-coital bleeding (PCB)
- Chaotic bleeding: constant and not regulated at all
- functional abnormality: endometrium is normal but something is not working functionally
What are pathological causes of abnormal vaginal bleeding?
- fibroids (submucosal)
- adenomyosis
- endometrial pathology
- cervical pathology
- pregnancy
- cervical ectropion
What kinds of endometrial pathology can cause abnormal vaginal bleeding?
benign adenomas or polyps
hyperplasias
carcinoma
What kind of cervical pathology can cause abnormal vaginal bleeding?
polyps
carcinoma
infective: chlamydia
What are cervical ectropion caused by?
oestrogen expo
can result in abnormal vaginal bleeding
What is adenomyosis?
pockets of endometrium in the myometrium.
often caused painful, heavy periods
What are submucous fibroids?
fibroids: benign myometrium mass
submucous: fibroid poking into uterine cavity (can affect bleeding)
What is DUB?
dysregulated uterine bleeding
(= AUB)
Dx of exclusion (no identified organic cause of bleeding issues)
What is the significance of submucous fibroids?
associated with 3x increased risk of abnormal peri-menopausal bleeding
What is the significance of polyps?
more frequent in women with menstrual disorders or abnormal bleeding on HRT
What needs to be considered when dealing with abnormal bleeding?
- exclude pregnancy
- exclude cervical pathology
- exclude focal intracavity pathology (polyps, submucous fibroids)
- consider endometrial pathology for >40yo
[use the least invasive method to achieve this]
What are the important points in the history to consider in abnormal vaginal bleeding?
- last menstrual period
- regular or irregular periods
- inter-period bleeding
- heavy clots? flooding?
- post-coital bleeding?
- pain
- medication
- smoking history
- smear
- past operations
- contraception: is family complete?
N.B. progesterone contraception can cause irregular bleeding
What points in examination are important to consider for abnormal vaginal bleeding?
- BMI
- Abdo: distension, scars, pain, masses
- Bimanual: uterine size, adnexal masses, pain
- cervix: polyps, suspect lesions
Why is BMI an important consideration for abnormal uterine/vaginal bleeding?
if overweight then will be hyper-oestrogenic
peripheral fat depots make oestrogen
What investigations should be done for abnormal vaginal/uterine bleeding?
- pregnancy test (if appropriate)
- Haemaglobin (if heavy bleeding)
- swabs: endocervical (for chlamydia)
- transvaginal USS
- endometrial sampling (biopsy)
- hysteroscopy (in-patient or OPD)
What kind of anaemia is most common with heavy uterine bleeding?
iron-deficiency anaemia
What is transvaginal sonography (TVS)?
- can assess relationships of fibroids to the cavity
- high detection rate for polyps
- assess function: anovulatory cycles
- assess tubal and ovarian pathology
- well-accepted by patients
- cheap with few complications
What are the limitations of transvaginal sonography (TVS)?
good for focal pathology
not good for predicting endometrial pathology: biopsy still needed for many cases
periovulatory or post-menstrual endometrium: difficult to gauge endometrial thickness
What is the use of hydrosonography?
used in conjunction with TVS
allows separation of 2 layers to see in between
What is the normal endometrial thickness (ET) in pre-menopausal women?
6mm post-menstrual
12mm (max.) anytime in cycle
[arbitrary values]
When is a hysteroscopy indicated?
- if TVS is abnormal
- no response to medical therapy
- multiple risk factors for endometrial pathology
What are the risk factors for submucous fibroids?
- obesity
- nulliparity
- early menarche/late menopause
- hypertension
- DM
- anovulation e.g. PCOS
- FHx breast/endometrual/colonic Ca (CA-125 Ag)
What is the classical presentation for endometrial Ca or PCOS?
obesity
HT, DM
peri-menarche
[Metabolic X syndrome]
What is the main cause of endometrial hyperplasia?
unopposed oestrogen (E2) with no progesterone e.g. anovulatory
can Rx with progesterone to balance
What are the 3 types of endometrial hyperplasia?
- simple (benign)
- atypical (aka dysplastic, not benign and on its way to malignant)
- carcinoma
What are the Rx for polyps?
SURGERY
transcervical removal of polyps (TCRP)
vs
polypectomy
TCRP is a more definitive removal, less chance of polyp returning)
What are the Rx for fibroids?
MEDICAL
Mirena coil IUS
SURGERY
transcervical removal of fibroids (TCRF)
Myomectomy (requires abdo approach)
Hysterectomy (total/subtotal abdo, vaginal)
What is a contraindication for Mirena IUS?
abnormal uterine cavity
e.g. multiple uterine fibroids
What are the consideration for Rx for DUB?
does she want or need Rx?
does she need contraception/pregnancy?
how much is it affecting QoL?
is she physically compromised?
What are the Rx options for DUB?
- nothing
- Medical: hormonal vs. non-hormonal
- Surgery
What are the non-hormonal Rx options for DUB?
ANTI-FIBRINOLYTIC
40-50% reduction in blood loss
e.g. TXA
MEFENAMIC ACID
30% reduction in blood loss
What are the hormonal Rx options for DUB?
COCP
20-30% reduction in blood loss
MIRENA IUS
90% reduction
[progestagens are not beneficial for blood loss, used to control cycle length in anovulatory DUB]
How does mefenamic acid work to control DUB?
menorrhagia: more dilatory PGs present
Mefenamic acid shifts the PGs to reduce the vasodilatory PGs
=> specific effect on bleeding loss and pain Mx in uterus
What are the surgical options for Rx DUB?
- endometrial resection/ablation
- hysterectomy (vaginal/abdominal, more commonly laproscopic)
- oophorectomy
What is the most common surgical Rx for DUB?
radio frequency ablation (produced heat) of endometrium
-permanent frying of endometrial tissue
What is Ponstan?
trade name for Mefenamic acid
