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Ovarian Hyperstimulation Syndrome – Causes, Symptoms and Treatment

Verified By Apollo Gynecologist November 25, 2021 1830 0
Ovarian Hyperstimulation Syndrome
Ovarian Hyperstimulation Syndrome

Ovarian hyperstimulation syndrome (OHSS) refers to an amplified response of female hormones. It occurs when injectable hormone medications are given to stimulate the ovaries. Mild cases of OHSS improve on their own, while severe cases require hospitalization.

What is ovarian hyperstimulation syndrome?

Ovaries are the internal female reproductive organs that produce eggs as well as the hormones  estrogen and progesterone. While the exact cause of ovarian hyperstimulation syndrome isn’t fully understood, it has something to do with high levels of human chorionic gonadotropin (HCG). Ovarian blood vessels react abnormally to HCG and begin to leak fluid. This fluid swells the ovaries, and sometimes large amounts move into the abdomen. During fertility treatments, HCG may be given as a “trigger” so that a mature follicle will release its egg. OHSS usually happens within a week after you receive an HCG injection. If you become pregnant during a treatment cycle, OHSS may worsen as your body also begins producing its own HCG in response to the pregnancy.


What are the symptoms of ovarian hyperstimulation syndrome?

Symptoms of ovarian hyperstimulation syndrome can be mild, moderate or severe. Most women experience them within one to two weeks after injecting gonadotropins.

  1. Mild to moderate symptoms of OHSS
  2. Moderate abdominal pain
  3. Bloating and feeling full
  4. Nausea and vomiting
  5. Pain in the pelvis due to tender ovaries

In most women, a mild ovarian hyperstimulation syndrome resolves on its own.

Severe symptoms of OHSS

  • Rapid weight gain — more than 2.2 pounds (1 kilogram) in 24 hours
  • Severe abdominal pain
  • Severe, persistent nausea and vomiting
  • Blood clots
  • Decreased urination
  • Shortness of breath
  • Tight or enlarged abdomen

A severe form of ovarian hyperstimulation syndrome requires urgent hospitalization and medical attention.

When do you need to see a doctor?

If you are undergoing any fertility treatments or have currently received hormonal injections, look for the symptoms mentioned above, even the mild ones, which does require a visit to the doctor.


Call 1860-500-1066 to book an appointment.

How can you prevent ovarian hyperstimulation syndrome?

OHSS can affect any woman taking fertility medications, especially injectable hormones.

Here are some preventive strategies your healthcare team can come up with:

  • Your doctor might use a minimum dosage of injectables capable of stimulating ovulation.
  • Your doctor may use alternate medications that reduce the risk of OHSS without affecting the odds of pregnancy. These include low-dose aspirin; dopamine agonists such as carbergoline or quinogloide; and calcium infusions.
  • Coasting. If your estrogen level is high or you have a large number of developed follicles, your doctor may have you stop injectable medications and wait a few days before giving HCG, which triggers ovulation. This is known as coasting.
  • Avoiding use of an HCG trigger shot. Because OHSS often develops after an HCG trigger shot is given, alternatives to HCG for triggering have been developed using Gn-RH agonists, such as leuprolide .
  • Freezing embryos. If you’re undergoing IVF, all the follicles (mature and immature) may be removed from your ovaries to reduce the chance of OHSS. Mature follicles are fertilized and frozen, and your ovaries are allowed to rest. You can resume the IVF process at a later date, when your body is rea

What are the complications of ovarian hyperstimulation syndrome?

Complications predominantly occur in critical cases of OHSS. They include:

  • Fluid collection in the abdomen and sometimes the chest
  • Electrolyte disturbances (sodium, potassium, others)
  • Blood clots in large vessels, usually in the legs
  • Kidney failure
  • Twisting of an ovary (ovarian torsion)
  • Rupture of a cyst in an ovary, which can lead to serious bleeding
  • Breathing problems
  • Pregnancy loss from miscarriage or termination because of complications
  • Rarely, death

What are the treatment options for ovarian hyperstimulation syndrome?

Mild OHSS can resolve on its own. Treatment options for moderate and severe are:

  1. Treatment for moderate OHSS
  2. Adequate intake of fluids
  3. Visit to a medical facility for timely physical examinations and ultrasounds
  4. Measuring your waistline and weight to track any immediate changes
  5. Keeping a record of your urine flow and volume
  6. Blood tests to monitor for dehydration, electrolyte imbalance and other problems
  7. Drainage of excess abdominal fluid using a needle inserted in your abdominal cavity
  8. Medications to prevent blood clots (anticoagulants)

Treatment Options for Severe OHSS

With severe OHSS, you may need to be admitted to the hospital for monitoring and aggressive treatment, including IV fluids. Your doctor may give you a medication called cabergoline medications or gonadotropin-releasing hormone (Gn-RH) antagonists or letrozole to help suppress ovarian activity.

Serious complications may require additional treatments, such as surgery for a ruptured ovarian cyst or intensive care for liver or lung complications. You may also need anticoagulant medications to decrease the risk of blood clots in your legs.


Ovarian hyperstimulation syndrome is a condition wherein injectable hormones can cause disturbances in the body. Mild OHSS symptoms might not need hospitalization. There are multiple strategies your doctor can adopt to prevent the incidence of ovarian hyperstimulation syndrome. Your doctor might recommend freezing embryos if OHSS is worsening. It will allow you to undergo IVF at a later stage with more significant chances of success.

Frequently Asked Questions (FAQs)

How common is OHSS?

Women with polycystic ovary syndrome are at more considerable risk of developing OHSS. Mild OHSS, resolvable on its own, can occur in around a quarter of patients. Severe or critical OHSS is uncommon.

When will I recover from ovarian hyperstimulation syndrome?

Most women with mild OHSS recover within one to two weeks after developing the symptoms. In some cases the doctor will freeze the embryos and continue IVF once the body is ready.

What are the specific home-care strategies for OHSS?

  • Try an over-the-counter painkiller such as acetaminophen  for abdominal discomfort, but avoid ibuprofen or naproxen sodium if you have recently had an embryo transfer, as these drugs can interfere with implantation of the embryo.
  • Avoid sexual intercourse, as it may be painful and can cause a cyst in your ovary to rupture.
  • Maintain a light physical activity level, avoiding strenuous or high-impact activities.
  • Weigh yourself on the same scale and measure around your abdomen each day, reporting unusual increases to your doctor.
  • Call your doctor if your signs and symptoms get worse.
Verified By Apollo Gynecologist
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