Ovulation Disorders Flashcards
oligomenonrrhea
reduction in the frequency of periods to less than 9 a year (menstrual cycles lasting longer than 35 days)
anovualtion is the
failure to ovulate and is mostly associated with oligo- or amenorrhoea
assessing ovualtion
regular menstrual cycle is highly suggestive that ovulation is taking place but it can be confirmed by measuring mid-luteal (day 21) progesterone levels: >30nmol/L confirms ovulation has occurred
WHO classification of ovulation disorders
Group 1: Hypothalamic pituitary failure
Group 2: hypothalamic pituitary dysfunction
Group 3: Ovarian failure
Group 1 ovulatory disorders
- hypothalamic pituitary failure
- hyopgonadotrophic hypogonadism
- low levels of FSH, LH and oestrogen
- normal prolactin levels
- accounts for 10% of ovulatory disorders
causes of hypothalamic pituitary failure
- kallmans syndrome
- functional hypothalamic amenorrhoea
- idiopathic hypogonadotrophic hypogonadism
- hypopitauatarism
management of group 1: hypothalamic pituitary failure
- stabilise weight by increasing BMI to a normal BMI of 18.5
- GnRH pump: pulsatile release of gonadotrophin releasing hormone
- Gonadotrophin (FSH and LH) daily injections but there is an increased multiple pregnancy rate
group 2: hypothalamic pituitary dysfunctions
- accounts for 85% of ovulatory disorders
- normal gonadotrophins but an increased LH:FSH ration, normal oestrogen levels
- causes oligo- or amenorrhoea
most common cause of group 2: hypothalamic pituitary dysfunction
polycystic ovarian syndrome (PCOS) but another causes is hyperprolactinaemia
PCOS is diagnosed in individuals with
2 out of the 3 of the Rotterdam criteria:
- oligo- or an ovulation
- clinical and/or biochemical evidence of hyperandrogenism
- polycystic ovaries on sonography : presence of 12 or more follicles within the ovary with a diameter of 2-9mm and/ or ovarian volume of 10cm3 or greater
insulin resistance
occurs in 80% of people with PCOS, insulin acts as a co-gonadotrophin to LH so increased insulin levels cause increased secretion of LH causing the overproduction of androstenedione, insulin also reduces levels of sex hormone binding globulin so increases the levels of free testosterone which is biologically active causing hyperandrogenism
general managent of people with PCOS in those wanting to get pregant
- weight loss
- smoking and alcohol cessation
- folic acid supplementation (400mcg per day if the female has no risk factors for neural tube defects) 5mg a day if the female is at high risk for neural tube defects
- rubella immunisation
risk factors for neural tube defects which require 5mg of folic acid
coeliac, previous pregnancy with neural tube defects, diabetes, sickle- cell anaemia, anti-epileptic medications, any family history on the mother or fathers side of neural tube defects
rubella immunisation
if a pregnant woman gets rubella it is catastrophic to the foetus therefore is a female wants to get pregnant they should be immunised if they are not already and because the vaccine is live attenuated females should not conceive for at least one month after they get the vaccine
medical management of PCOS for those wanting to get pregnant
first line= clomifine citrate which is an anti-oestrogen which is taken between days 2-6 of the menstrual cycle, there is a 10% risk of multiple pregnancy so ultrasound follicular monitoring is required
if ovulation is not achieved
on the lowest dose of clomifine citrate (50mg) then the dose can be increased to 100-150mg, but ovulation still does not occur in 10-15% of cases and this is called clomifene resistance
Second line treatment for PCOS for woman wanting to get pregnant
- gonadotrophin injections (RECOMBINANT FSH) but there is a risk of multiple pregnancy and overstimulate
- laparoscopic ovarian drilling but risk of irreversibly damaging the ovaries
role of metformin in ovulation induction
- improves insulin resistance and reduces androgen production
- in some woman causes the return of menstruation and ovulation
risks of ovulation induction
- ovarian hyperstimulation syndrome
- multiple pregnancies
- may or may not cause ovarian cancer (not enough current evidence to decide)
ovarian hyperstimulation syndrome
iatrogenic complications which occurs in 3-6% of females undergoing assisted reproduction, most common in woman undergoing IVF (10%)
risk factors for ovarian hyper stimulation syndrome
age less than 30, PCOS, low BMI, previous history of OHSS, pregnancy occurring duet the same round of IVF
OHSS is categorised as
mild moderate and severe depending on the symptoms
mild OHSS
abdominal bloating, pain, ovarian size less than 8cm
moderate OHSS
moderate abdominal pain, nausea, vomiting, ascites on ultrasound, ovarian size between 8-12cm
severe OHSS
ascites, haematocrit >55%, thromboembolism, ARDS
ovarian hyperstimulation syndrome most commonly occurs
after injection of HCG which is carried out before oocyte retrieval for IVF, this causes the ovaries to release inflammatory mediators especially VEGF which causes increase capillary permeability causing fluid to shift from the intravascular compartment to the third space compartment
risks of multiple pregnancy
- increased risk of hyperemesis gravidarum
- anaemia
- 3x risk of pre-eclampsia and 3x risk of gestational diabetes
- increased risk of early and late miscarriage, low birth weight, prematurity, disability, still-birth/ neonatal death
- twin to twin transfusion syndrome
monochorionic twins
have a 3x greater perinatal mortality risk than dichorionc twins
(monochorinons means the twins are in the same sac, dichorionic means the twins are in different sacs)
Twin to twin transfusion syndrome
occurs when there is an imbalance in the placenta blood vessels which connect both twins, one twin (recipient twin) gets excess blood while the other twin doesn’t get enough (donor twin)
recipient twin develops
polyhydroamins meanwhile the donor twin develops oligohydroamins
twin to twin tranfusion syndrome
is fatal if left untreated, treatment is laser division of placental vessels. amnioreduction or septostomy
group 3 ovulations disorders
- ovarian failure
- accounts for only 5% of all ovulation disorders
most common cause of ovarian failure
premature ovarian failure
- hypergonadotrophic hypogonadism
- low levels of oestrogen and high levels of FSH and LH
premature ovarian failure is diagnosed if
FSH levels are greater than 30 on 2 occasions more than one month apart
management of ovarian failure
hormone replacement therapy
