What Is Ovarian Hyperstimulation Syndrome?

Ovarian hyperstimulation syndrome (OHSS) is one of the main complications of assisted reproduction in vitro fertility. It is an overreaction of the human body to ovulation-promoting drugs. A series of clinical symptoms caused by sexual abnormalities, abnormal body fluids and protein extravasation into the third space of the human body. The main clinical manifestations of OHSS are cystic enlargement of the ovary, increased capillary permeability, and accumulation of body fluids in the interstitial space, causing peritoneal effusion and pleural effusion, with local or systemic edema. In recent years, the occurrence of OHSS has shown an upward trend, which has attracted more and more attention of clinical medical workers.

Basic Information

English name

ovarian hyperstimulation syndrome

Visiting department

Obstetrics and Gynecology

Common locations

Ovary

Common causes

OHSS can occur after various follicles are stimulated, the ovaries are highly sensitive to ovulation-promoting drugs (high-sensitivity ovaries), endogenous HCG secretion during early pregnancy, etc.

Common symptoms

Increased cystic ovaries, increased capillary permeability, and accumulation of body fluids in the interstitial space, causing peritoneal effusion and pleural effusion, with local or systemic edema

Causes of Ovarian Hyperstimulation Syndrome

OHSS can occur after various follicles are stimulated. The main high-risk factors related to OHSS are:

1. The ovary is highly sensitive to ovulation-promoting drugs (high-sensitivity ovaries): It is common in patients with polycystic ovary and young (<35 years) thin.

2. Use HCG to promote ovulation or maintain the corpus luteum of pregnancy.

3. Endogenous HCG secretion during early pregnancy.

4. Previous medical history of OHSS.

Clinical manifestations of ovarian hyperstimulation syndrome

The main clinical manifestations of OHSS are cystic enlargement of the ovary, increased capillary permeability, and accumulation of body fluids in the interstitial space, causing peritoneal effusion and pleural effusion, with local or systemic edema. Generally, OHSS can be divided into light, medium (incidence rate of 3% to 6%), and heavy degree (incidence rate of 0.1% to 2%).

Due to the large ovaries in some patients, acute abdomen such as ovarian torsion and flavin cyst rupture and bleeding may occur. Divided into three levels of light, medium and severe. Mild: Symptoms and signs appear more than 3 to 7 days after HCG injection, manifested as bloating, poor appetite, lower abdominal discomfort, heavy feeling, or mild lower abdominal pain. B-ultrasound examination showed an enlarged ovary with a diameter 5cm. Moderate: obvious abdominal pain, nausea, vomiting, thirst, occasional diarrhea, weight gain 3kg. B-ultrasound examination showed an enlarged ovary with a diameter of 5 to 10 cm and 4.5 kg of peritoneal effusion. Because a large amount of thoracic and abdominal effusion can lead to reduced blood volume, blood concentration, hypercoagulable state of blood, hypovolemic shock, severe heart and lung dysfunction, electrolyte imbalance, impaired liver and kidney function, thrombosis, and respiratory distress in adults. Sign up.

Ovarian hyperstimulation syndrome test

Laboratory and ultrasound examinations for patients with suspected OHSS should be monitored for whole blood cell analysis, liver and kidney function tests, water and electrolyte determination, pelvic ultrasound examination, weight measurement, and estradiol (E2) level measurement. Observing the ovarian response to gonadotropins is an important measure to prevent OHSS.

1. OHSS can be manifested as increased blood cell volume and white blood cell count, hyponatremia and hypoproteinemia.

2. Ultrasound showed ovarian enlargement, follicular flavin cysts, mild ovaries enlarged 5-7 cm, moderate 7-10 cm, severe 10 cm or more. At the same time, peritoneal effusion, pleural effusion, or pericardial effusion can be seen.

3. Severe OHSS can appear liver dysfunction (expressed as liver cell damage) and cholestasis, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, bilirubin, creatine kinase increase, usually return to normal within 1 month.

4. Liver biopsy showed liver steatosis, Kuffer cell proliferation, and peritoneal effusion was exudate, which contained a higher concentration of protein.

Diagnosis of ovarian hyperstimulation syndrome

1. Based on medical history and clinical manifestations

Weight gain, thirsty abdominal discomfort, slight swelling in the lower abdomen, mild nausea, and vomiting.

2.B-ultrasound display

The ovary is enlarged (> 5 cm in diameter), there are multiple corpora lutea, and a small amount of fluid is seen in the abdominal cavity.

3. Increased blood cell volume and white blood cell count, hyponatremia, hypoproteinemia

In severe OHSS, liver dysfunction (expressed as liver cell damage) and cholestasis can occur, and alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, bilirubin, and creatine kinase are increased.

4. Suspected OHSS

Should be done for whole blood cell analysis, liver and kidney function tests, water and electrolyte determination, pelvic ultrasound examination, weight measurement, E ₂ level determination and so on.

Ovarian hyperstimulation syndrome complications

Vascular complications

The most serious complications are as follows:

(1) Deep venous thrombosis of lower limbs can be divided into central, peripheral and mixed types.

(2) Deep vein thrombosis of the upper limbs.

2. Abnormal liver function

25% to 40% of OHSS patients have abnormal liver function and can last for more than 2 months.

3. Respiratory complications

Dyspnea and shortness of breath are the most common clinical manifestations of the respiratory tract, occurring in 92% of OHSS cases.

4. Kidney complications.

5. Ovarian torsion and ovarian rupture

Reversal of normal-sized ovaries is rare. After ovulation promotion, the ovarian volume increases, weight increases, and twist rate increases.

Ovarian Hyperstimulation Syndrome Treatment

OHSS is a self-limiting disease that occurs 3 to 7 days after HCG injection. If not pregnant, the course of the disease is about 14 days; if pregnant, it will continue for a period of time, and the condition may worsen.

Mild

Generally, no special treatment is required. Patients are encouraged to get more water. Most patients can recover within 1 week.

2. Moderate

Instruct patients to self-test, including bed rest, intake of sufficient fluids, monitoring of abdominal circumference, urine output and weight, and some patients can be hospitalized for observation.

3. Severe

Should be hospitalized. The purpose of treatment is to maintain sufficient blood volume, correct blood concentration, maintain normal urine output, improve symptoms to the greatest extent, and avoid severe complications such as shock, thromboembolism, water-electrolyte balance disorders, and abnormal liver and kidney function.

(1) Closely monitor the changes of various vital signs.

(2) Symptomatic treatment: Take a break and enter a high-protein diet. Drink a small amount of water early in the morning, and add saline and glucose in time to increase urine output. Volume expansion The intravenous infusion of human albumin is preferred, which helps maintain the plasma colloid osmotic pressure and effective blood volume, and reduces free estrogen and some harmful factors. To reduce the leakage of fluid to the chest and abdominal cavity, prednisone tablets can be taken orally. Prevention of thrombosis Encourage patients to turn over, move their limbs, massage their legs, and take enteric-coated aspirin tablets. Severe cases require anticoagulation. Treatment of peritoneal effusion When there is an indication, abdominal drainage is feasible. Treatment of pleural effusion is rare. If pleural effusion is often on the right side, sometimes pleural effusion and peritoneal effusion appear simultaneously.

(3) OHSS should be treated when ovarian rupture and severe internal bleeding occur. When there is a twist, you can raise your hips and change your position, and you can usually relieve yourself. If necessary, surgical treatment.