DUB, Ovarian Function and Anovulation (7.2) Flashcards
To be familiar with: Ovarian structure The two main ovarian functions The HPO axis & Ovulation The mechanisms of anovulation The WHO classification of anovulation
State the 2 main functions of the ovary
- Ovulation: To perform the maturation and release (through ovulation) of the oocyte
- Endocrine: To secrete oestradiol and progesterone
Outline the HPO axis

Outline the process of ovulation
The ovulatory cycle:
- Recruitment: Around 5 follicles per follicular phase
- Selection: The most dominant tertiary follicle is selected following the FSH window (5 days)
- Atresia
⋆ FSH window: [FSH] above the threshold level. Allows for the development and selection of the most domiannt follicle.
Outline the process of folliculogenesis
- Takes 3 ovarian cycles for complete maturation of the follicle - see wikipedia image

Define anovulation and its possible mechanisms
Anovulation: Failure to release a mature ovum, in preparation for fertilisation, through ovulation
Possible mechanisms:
Ovulatory failure: Failure to ovulate
Ovulatory dysfunction: Irregular ovulation. Failure of the oocyte to mature and undergo ovulation
Ovarian failure: Depletion of oocytes
Outline the WHO classification of anovulation
Define NUB (normal uterine bleeding) and its mechanism
Cyclical shedding of the endometrial lining, under hormonal control. Occuring approximately every 28 days.
Oestrogen release, triggered by FSH, causes proliferation of the endometrial lining. Oestrogen creates a positive feedback loop, causing a mid-cycle surge in LH, allowing for ovulation and subsequent menses.
Mechanism:
- Shedding of the endometrial stratum functionalis
- The endometrial stroma ‘shrink’
- Spiral arterioles vasoconstrict (as vasodilatory progesterone is lost) and hypoxia follows. Prostaglandin synthesis and inflammation result → dysmenorrhoea.
Duration: 3-5 days
Amount: 40 ml on average
AUB: State the ‘regular’ variations
Menorrhagia - heavy/prolonged menses (heavy = > 80 ml)
Oligomenorrhea - light/infrequent menses
Polymenorrhea - Short cycle length
Amenorrhea - Absence of menses
AUB: State the ‘irregular’ variations
Metrorrhagia - Frequent and irregular (between menstrual periods)
Intermenstrual
Postcoital
Post-menopausal
AUB: State the possible causes
⋆ Structural: PALM
⋆ Functional: COIN
Structural: PALM
Polys
Adenomyosis
Leiomyoma (fibroids)
Malignancy
Functional: COIN
Coagulopathy
Ovulatory (endocrine)
Idiopathic
Not yet classified
Outline the assessment/diagnosis of AUB
1. Symptomatology:
Pattern & severity: Menstrual diary
Impact on health & QOL
Associated symptoms: Pelvic pain, anaemia, weight loss, urinary/bowel symptoms
2. Underlying pathology
Nature, extent/severity
3. Patient’s circumstances
Demographics: Age, social, fertility
Medical background: DM, obesity, PCOS, BP, thyroid disease
Drug Hx: Iron, anti-coagulants
Examination
- Check for pelvoc:abdominal mass
- Check cervix (polyps), uterus and adnexa
Investigations
Imaging: USS (ultrasound scan), MRI
Hysteroscopy: Used for polyps and suspected uterine pathology
Endometrial biopsy
Outline possible management strategies for AUB
Structural causes:
-
Medical
- Adenomyosis:
Non-hormonal: NSAIDs, transexamic acid
Hormonal: COCP, progestogens, Mirena IUS, GnRH agonist
-
Surgical:
- Fibroids: Removal or uterine artery embolization (stops growth of the mass)
Functional causes:
- Non-hormonal: NSAIDs, tranexamic acid (anti-fibrinolytic)
- Hormonal: COCP, progestogens, Mirena IUS, GnRH agonist
- Treat cause: Applicable for thyroid disease, blood disorders, fibroids, anaemia
- Endometrial ablation: Can be used if conservative treatment is unsuccessful. May use novasure (scrape), thermal balloon or hyrothermal ablation.
- Hysterectomy
AUB: Outline the mechanism of ovulatory AUB
Anovulation → Lack of progesterone (no corpus luteum) → Excessive endometrial proliferation which eventually exceeds the structural support matrix → Endometrium breaks down → heavy menses (?)
AUB: State coagulopathies which may lead to AUB
Bleeding may be increased due to:
- Von Willebrand disease ⇒ less coagulation and more bleeding
- Thrombocytopenia (low platelet levels)
- Vitamin K deficiency (dependent clotting factors)
- NSAIDs, penicillin
- Anti-coagulant treatments
Structual causes of AUB: State the risk factors for malignancy
- PCOS
- > 45 years
- Obesity
- Hypertension
- Diabetes
Structural AUB: Outline how polys may cause AUB
May cause excessive menstrual bleeding, post-coital bleeding or intramenstrual spotting
Structural AUB: Outline adenomyosis and its symptoms
Adenomyosis: Growth of endometrial tissue within the myometrium of the uterus
Symptoms:
- Heavy, painful and irregular periods
- Pre-menstrual pelvic pain
- ‘Fullness’ in the pelvis
Structural AUB: Outline leiomyoma and its symptoms
Leiomyoma: Growths of smooth muscle and fibrous tissue
Symptoms
- Menorrhagia
- Intermenstrual and post-coital bleeding
- Abdominal pain
- Pain during intercourse
Define Chronic Pelvis Pain (CPP) and the associated risk factors
Pelvic pain persisting for > 6 months
Aetiology:
- May be resultant of limbic lobe dysregulation
- The psychological effects of physical abuse lead to disregulation of the cingulate gyrus, amygdala and insular cortex
- Centrally mediated allodynia (pain from a non-noxious stimuli) without end-organ pathology
Risk factors:
- Single, separated, divorced
- PID
- Pregnancy
- Endometriosis
- Previous CS
- Hx of sexual abuse
- Hx of drug/alcohol abuse
Outline the possible causes of CPP
Gynaecological:
- Endometriosis
- Adhesions
- Ovarian Cyst
- Fibroid
Non-gynaecological
- Bowel
- Urinary
- MSK
- Neuropathic
- Psychological
Unexplained
Define endometriosis, possible theories and its pathology
Endometriosis: Ectopic growth of endometrial stroma/glands outside of the uterine cavity
Possible theories:
- Retrograde menstruation and perineal implantation
Pathology: Ectopic growth of the oestrogen sensitive tissue leads to bleeding in these areas. Inflammation leads to scarring and adhesions. This may then cause CPP.
Inflammation → fibrosis → adhesions → CPP
Outline the symptoms associated with endometriosis
- Dysmenorrhoea (62 %)
- Dyspareunia
- Non-cyclic pain
Associated non-gynaecological symptoms:
- Urinary: Haematuria and dysuria
- Bowel disturbances: Dyschezia, tenesmus
- Pain/symptoms worsen around period
All pain and symptoms worsen around the time of menses
Outline the management of endometriosis
Pain management: Paracetamol, NSAIDs
Hormonal treatment:
- Pseudopregnancy: Progesterone (POP), COCP
- Pseudomenopause: GnRH analogues
Surgery:
- Conservative: Ablation, cystectomy (removal of ‘chocolate’ cysts)
- Radical: Hysterectomy