Introduction to PCOS Flashcards
Why is it important to learn about PCOS?
Arguably the most prevalent medical condition in women
Patients with PCOS have systemic metabolic manifestations with multiple symptomatology, some of these are:
endocrine, gynaecological, diabetic, dermatological, eating disorder, psychiatry
Insulin resistance (IR) likely to have a life-long impact on patient.
Obesity has a bigger impact on PCOS population compared to normal, especially regarding IR
Annual economic cost of diagnosis and treatment of PCOS in USA recently calculated to be $4.36 billion and 40% of this was IR/T2D-related
What are the physical signs of polycystic ovaries?
The ovary contains increased numbers (>20) of small antral follicles (2-9mm) visible on high quality transvaginal u/s transducers
Disorder of follicle growth at all stages
Possibly increased proportion of primordial follicles & increased number of activated (primary) follicles
Arrested antral follicle growth before they mature
Lower rates of atresia » antral follicles persist (visible on u/s). In some cases there is a failure of dominant follicle selection and therefore anovulation
The main problem with PCOS is that there is a …
Disorder of follicle growth occurs across all stages
What is displayed on an ultrasound in PCO?
Not cysts but follicles that have stopped growing
What was PCOS originally described as?
First described in 1935 by Stein and Leventhal -
syndrome described as obesity, hirsutism and anovulation in the presence of bilaterally enlarged sclerocystic ovaries.
How might have PCOS been originally found?
Through biopsies
Changes in diagnosing PCOS now
Discovered that many women have the change in the ovaries and do not necessarily have the symptoms
Spectrum of presentation has led to lack of consensus regarding the definition
Diagnosis of exclusion i.e. disorders that mimic PCOS include:
Non-classical adrenal hyperplasia (most common is deficiency of 21-hydroxylase → ↑17-hydroxyprogesterone & androgens)
Hyperprolactinemia, thyroid disease, Cushing’s syndrome
Ovarian hyperthecosis (very rare) - nests of luteinized theca cells
sclero-cystic=
Sclero-cystic = hardened or stiff
Inital PCOS diagnosis (extra)
Initially diagnosis by laparotomy and visually examination – no ultrasound or laparascopes, now diagnosed routinely by U/S (since 1980s).
Ovarian hyperthecosis – excess androgen production due to nests of luteinized theca cells scattered throughout ovarian stroma. Ovary slightly enlarged but devoid of antral follicles – hence distinct from PCOS. Serum testo levels>women with PCOS but <from androgen-secreting tumours.
What is the Rotterdam Criteria?
According to the Rotterdam consensus, polycystic ovarian syndrome (PCOS) is defined by the presence of two of three of the criteria
What are the 3 possible criteria for diagnosing PCOS according to the Rotterdam criteria?
1) Polycystic ovaries (20 or more follicles measuring 2-9mm diameter and/or increased ovarian volume >10ml in either ovary & no DF >10mm)
2) Ovulatory Dysfunction (Oligomenorrhea/anovulation)
3) Hyper-androgenism (clinical/biochemical evidence)
How are polycystic ovaries diagnosed?
Technique and equipment dependent. T/V imaging not always appropriate
How is an ovulatory dysfunction diagnosed?
Frequent bleeding <21d or infrequent bleeding >35d. To confirm ovulation serum progesterone level at mid-luteal phase (d21-22) of cycle (values ≥7ng/ml needed for regular luteal function)
How is hyper-androgenism diagnosed?
Assays not standardized across labs; normative data not clearly defined; clinical hyperandrogenism difficult to quantify; ethnicity
What does Clinical hyperandrogenism include?
hirsutism, acne, or male pattern alopecia or biochemical signs of hyperandrogenism i.e. elevated levels of total or free testosterone.
What is anovulation?
Anovulation is either frequent bleeding at intervals <21d or infrequent bleeding at intervals of >35d.
Normal ovulation is hard to define – mid-luteal Progesterone <3-4ng/ml indicates oligo-anovulatory. Chang et al reported that 16% of 316 women with PCOS had normal-appearing cycles, despite having oligo-anovulation
What does a normal ovary look like?
≤5 follicles in an ovary with a small amount of stroma
What does an anovulatory PCO look like?
≥ 20 follicles, 2-9mm diameter arranged peripherally around an enlarged core of dense stroma - ovarian volume >10mls, with NO dominant follicle
What does an ovulatory PCO look like?
Dominant follicle persists
Describe the refinement of PCOS diagnostic criteria and phenotypes
Still have 3 diagnostic criteria but with 4 phenotypes (A, B, C and D):
Phenotype A: Hyperandrogenism, Ovulatory Dysfunction and PCOM
Phenotype B: Hyperandrogenism and Ovulatory Dysfunction
Phenotype C: Hyperandrogenism and PCOM
Phenotype D: Ovulatory Dusfunction and PCOM
Significance of Phenotypes
Phenotypes A&B are considered classic PCOS → (2/3 of cases) and also common in these phenotypes is BMI and metabolic syndrome
Phenotype C (ovulatory PCOS) → BMI is often normal, but if BMI increases can alter phenotypic presentation
Phenotype D (normoandrogenic PCOS) includes chronic anovulation and PCOM but normal serum androgens and no HA
Characteristic of anovulatory PCO?
No period for 6 months but you can see a CL and CA – so she had ovulated at some stage. Also see the ring of follicles and dense stroma and white thick tunica – so laparascopically would appear like a shiny ovary.
Characteristic of ovulatory PCO?
Dissected the stroma to show the DF, which is so large it pushes everything out of the way.
Most women with PCOM probably have regular or almost regular cycles
Most women with PCOS and cycle problems have oligomenorrhoea
There are a number of candidates for follicle arrest, they include:
androgens,
intra-follicular inhibitors eg AMH
defect in apoptosis
dysregulated gonadotrophin secretion (both FSH and LH)
What is the main difference between ovulatory and anovulatory PCO?
Main difference between ov and anov is also the level of insulin resistance. Adult rhesus macaques fed a western style diet (high fat/sugar) & exposed to chronically elevated T from pre-puberty to menopause altered small AF numbers, morphology and transcriptome (Bishop CV et al, 2015, Fertil.Steril.)
Prevalence of PCOS
32% of patients with amenorrhoea
87% with oligomenorrhoea
87% with hirsutism and regular cycles
75% of bulimics? [secretly binge — eating large amounts of food with a loss of control over the eating — and then purge, trying to get rid of the extra calories in an unhealthy way]
22% of ‘normal’ population
Prevalence of PCOS
32% of patients with amenorrhoea
87% with oligomenorrhoea
87% with hirsutism and regular cycles
75% of bulimics? [secretly binge — eating large amounts of food with a loss of control over the eating — and then purge, trying to get rid of the extra calories in an unhealthy way]
22% of ‘normal’ population
