Ovarian hyperstimulation syndrome (OHSS) is an exaggerated response to ovulation induction therapy. It has multiple causes including fertility drugs like gonadotropins and hCG, as well as spontaneous cases linked to conditions like hypothyroidism. OHSS results from increased vascular permeability and third spacing of fluid due to high VEGF levels stimulated by hCG. Symptoms range from mild abdominal discomfort to life-threatening complications involving multiple organ systems. Treatment involves hospitalization, aggressive IV hydration, albumin supplementation, and sometimes paracentesis or pleural drainage for severe cases. Prevention relies on individualizing drug regimens and monitoring ovarian response closely.

1. Ovarian Hyperstimulation Syndrome
(OHSS)
Prepared By:
Hemin Jamal

2. Definition
 Ovarian hyperstimulation syndrome (OHSS) is an
exaggerated response to ovulation induction therapy

3. Causes
 Fertility drugs
 Injections
 Gonadotropins( anovulation and ovarian stimulation)
 Human chorionic gonadotropin(maturation of egg)
 Gonadotropin-releasing hormone(to suppress the LH surge)
 Oral
 Clomiphene citrate (anovulation and ovarian stimulation)

4.  Spontaneous OHSS (without medication)
 Hydatiform mole
 multiple pregnancy
 Hypothyroidism

5. F
F
F
F
F F
F
F
F
F F
Stimulation Multiple follicles
VEGF
VEGF
VEGF
VEGF
VEGF
Bloodvessel
Ovary
enlargement
t
Production of
VEGF
Increase
permeability
Shift of fluid to
3rd space
edema
ascites
Effects
Risk
factors
Pathophysiology Endo hCG
Upregulate
F F
F F
F
F
F
Mature
Mature
Mature
Mature
Mature
VEGF
Mature

6. Risk factors
Primary risk factors (patient-related):
1. Young age
2. Previous OHSS
3.polycystic ovary syndrome (PCOS)
4.Low body weight
Secondary risk factors ( ovarian response related); On day of
hCG trigger:
1. High number of medium/large follicles
2. High or rapidly rising E2 levels
Pregnancy (increase in endogenous hCG)

7. Clinical presentation
 It occurs after 10 days oocyte retrieva
 correlated to endogenous hCG produ
by implanting embryo.
Onset
Late OHSSEarly OHSS
 It occurs within 9 days after
oocyte retrieval .
 correlated to ovarian response to
exogenous hCG stimulation.

8. Clinical presentation
Severity
CriticalMild to moderate Severe

9. Mild to moderate OHSS
 Mild to moderate abdominal pain
 Abdominal bloating
 Nausea
 Vomiting
 Diarrhea
 Tenderness in the area of ovaries

10. Severe OHSS
 Rapid weight gain — 2.3 kilograms in one day
 Severe, persistent nausea and vomiting
 Sever abdominal pain
 Shortness of breath
 Dark urine
 Dizziness/syncope
 Hemodynamic instability
 Edema
 Ascites

11. Critical
 Acute renal failure
 Arrhythmia(Electrolyte disturbances )
 Thromboembolism(hemoconcentration)
 Pericardial effusion
 Massive hydrothorax
 Adult RDS
 Ovarian torsion
 Rupture of a cyst in an ovary

12. Diagnosis
Laboratory investigations:
 Complete blood count (CBC) with differential:
 Hematocrit- >55%(hemoconcentration )
 Leukocyte count - >22,000 cells/µL is related to the seriousness
of OHSS
 Beta-hCG concentration
 A positive result indicates pregnancy.

13.  Estradiol levels
 Estradiol levels are increased
 estradiol >2000 pg/mL
 Complete metabolic panel
 Liver function test: AST, ALT , and ALP
 Renal function test: blood urea and creatinine
 Albumin and protein levels are decreased.
 Electrolyte imbalances: hyperkalemia and acidosis may be
present.

14. Imaging
 Ultrasonography
 to assess the follicles
 To measure the size of the ovaries
 to evaluate ascites
 Chest radiography
 may be indicated if dyspnea is present.

15. Treatment
Outpatient management
(follow up twice-weekly):
 mild & moderate OHSS.
 Severe OHSS
Inpatient management :

16. Conservative
 Education
 Fluid: the patient should receive plenty of of fluid (not less
than 1 liter).
 Activity: the patient should avoid vigorous activities
 Weight: should be recorded daily,
 urine output: the frequency and/or volume

17.  Pain relief:
- Symptomatic relief of abdominal pain can be achieved with
acetaminophen and if necessary oral or parenteral opiates.
 Nausea and/or vomiting
Antiemetic agents considered to be safe in early pregnancy
should be used to alleviate nausea and/or vomiting.

18. - Hospitalized patients should be considered at risk of thrombosis
secondary to hemo-concentration and immobilization.
- Full-length venous support stockings are recommended Daily
prophylactic doses of low-molecular weight heparin
(e.g., dalteparin sodium 5000 IU/day).
Thromboprophylaxis:

19. 1.Fluids and electrolytes:
 Hypovolemia correction
 Rapid initial hydration may be accomplished with a bolus
of IV fluid (500–1,000 mL). normal saline is preferable to
lactated Ringer’s solution.
 Albumin (25%) in doses of 50–100 g, infused over 4 hours
and, is an effective plasma expander when infusion of
normal saline fails

20.  Volume overload
Treatment with diuretics (e.g., furosemide, 20 mg IV) may be
considered after an adequate intravascular volume has been
restored (hematocrit <38%).
 Hyperkalemia
 calcium gluconate
 insulin
 sodium bicarbonate
 Kayexelate

21. 2.Paracentesis
 Indication
 Ascites with pain
 Ascites compromised pulmonary function
 oliguria/ anuria that does not improve
with appropriate fluid management
 Procedure
 A transvaginal or transabdominal approach may be used,
under gentle ultrasound guidance
 Replace plasma protein

22. 3- Pleuracentesis:
 Bilateral or severe pleural effusion
that persists after paracentesis
INTENSIVE CARE TREATMENT
renal failure
thromboembolism
adult respiratory distress syndrome

23. surgery
 Indications
 ovarian torsion
 a ruptured cyst in the ovary
 an internal hemorrhage
 Approach
 Laparoscopy(detorsion of ovaries )
 Laparotomy
 Preserve ovaries

24. prevention
 Recognition of risk factors for OHSS
 Ovulation induction regimens should be highly
individualized
 Use the minimum dose and duration of gonadotropin
therapy necessary to achieve the therapeutic goal.
 Monitoring(E2 and ultrasoography) and prophylactic
treatment with volume expanders