[20] Ovarian Hyperstimulation Syndrome Flashcards
What is the most serious consequence of ovulation due to assisted conception techniques?
Ovarian hyperstimulation syndrome
duh
What drugs more commonly cause ovarian hyperstimulation syndrome?
- hCG
- Human menopausal gonadotrophin
When is ovarian hyperstimulation syndrome more common with clomiphene?
In PCOS
What happens in ovarian hyperstimulation syndrome?
The ovary may form 20 follicles or more and swell due to increased levels of hCG
What is released from the hyperstimulated ovaries?
Vasoactive mediators
What happens as a result of the vasoactive mediators released by the hyperstimulated ovaries?
Increase in capillary permeability leading to a fluid shift from the intravascular compartment to the third space compartment such as the peritoneal or thoracic cavities
What can cause morbidity/mortality in ovarian hyperstimulation syndrome?
- Effusions
- Haemoconcentration
- Liver or kidney dysfunction
What effusions can cause problems in ovarian hyperstimulation syndrome?
- Pericardial
- Pleural
- Ascites
What is the risk of haemoconcentration in ovarian hyperstimulation syndrome?
Risk of thrombosis and coagulopathy
What proportion of IVF cycles have a mild degree of ovarian hyperstimulation syndrome?
1/3
What % of IVF cycles have a moderate degree of ovarian hyperstimulation syndrome?
3-6%
What % of IVF cycles have a severe ovarian hyperstimulation syndrome?
0.1-2%
What are the risk factors for ovarian hyperstimulation syndrome?
- PCOS
- Under 30
- Rapidly rising oestrogen levels and large number of follicles
- Use of hCG for luteal phase support
- Low body weight
When may symptoms of ovarian hyperstimulation syndrome first start?
Within 24 hours of hCG administration
When do symptoms of ovarian hyperstimulation syndrome tend to become severe?
After 7-10 days
What are the symptoms for mild to moderate ovarian hyperstimulation syndrome?
- Mild to moderate abdo pain
- Abdominal bloating and increased waist size
- Nausea and vomiting
- Diarrhoea
- Tenderness in area of ovaries
- Sudden weight increase of more than 3kg
What are the symptoms of severe ovarian hyperstimulation syndrome?
- Rapid weight gain e.g. 15-20kg in 10 days
- Severe abdominal pain
- Severe persistent nausea and vomiting
- Blood clots in legs
- Decreased urination
- Shortness of breath
- Tight or enlarged abdomen
What is classified as mild ovarian hyperstimulation syndrome?
- Abdominal bloating
- Mild abdo pain
- Ovarian size <8cm
What is classified as moderate ovarian hyperstimulation syndrome?
- Moderate abdo pain
- Nausea and vomiting
- USS evidence of ascites
- Ovarian size 8-12cm
What is classified as severe ovarian hyperstimulation syndrome?
- Clinical ascites
- Oliguria
- Haemoconcetration haematocrit >45%
- Hypoproteinaemia
- Ovarian size usually >12cm
What is classified as critical ovarian hyperstimulation syndrome?
- Tense ascites or large hydrothorax
- Haematocrit >55%
- WCC > 25x10^/L
- Thromboembolism
- ARDS
What monitoring is mandatory during drug treatment for IVF?
USS of ovaries
What is measured in the ovaries during IVF treatment?
Rate of follicle growth
What is done if rate of follicle growth in IVF treatment is excessive?
Treatment is cut back
What are the investigations in severe ovarian hyperstimulation syndrome?
- USS ovaries and abdomen
- FBC
- U&E’s and creatinine
- Coagulation screen
- LFTs
- CXR
- Measurement of abdominal girth
How is ovarian hyperstimulation syndrome managed?
Conservatively until resolves spontaneously
What happens if the patient is at risk of developing severe ovarian hyperstimulation syndrome?
hCG is withheld
What happens to IVF cycle if ovarian hyperstimulation syndrome occurs?
Egg collection and insemination can occur but embryo should be frozen and not implanted in that cycle
What are the key components to managing mild-to-moderate ovarian hyperstimulation syndrome?
- Analgesia
- Anti-emetics
- Increase oral fluids and drink according to thirst
What analgesics should be avoided in ovarian hyperstimulation syndrome?
NSAIDs
How often should women with ovarian hyperstimulation syndrome be monitored if managed in the community?
Every 1-2 days
Why may hospital admission be needed in moderate cases of ovarian hyperstimulation syndrome?
For prevention of thromboemoblism
What care setting may be required in severe ovarian hyperstimulation syndrome?
Intensive care
What monitoring is needed in severe ovarian hyperstimulation syndrome?
Fluid balance and electrolytes
What electrolyte imbalance is common in severe ovarian hyperstimulation syndrome?
Hyponatraemia
What immediate intervention can relieve symptoms of severe ovarian hyperstimulation syndrome?
Aspiration of ascites or pleural effusion
What are the potential complicatiqons of ovarian hyperstimulation syndrome?
- Thromboembolism
- ARDS
- AKI
- Ovarian torsion
- Death (rare)
How can the risk of ovarian hyperstimulation syndrome be reduced?
- Individualised stimulation regimes based on risk
- Use of GnRH analogues rather than hCG
- Freeze embryos and implanting in another cycle
- Use metformin in women with PCOS
What is the other significant risk of IVF?
Multiple pregnancy
