Ovarian hyperstimulation syndrome (OHSS) is a problem that is sometimes seen in women who take fertility medicines that stimulate egg production.
Normally, a woman produces one egg per month. Some women who have trouble getting pregnant may be given medicines to help them produce and release eggs.
If these medicines stimulate the ovaries too much, the ovaries can become very swollen. Fluid can leak into the belly and chest area. This is called OHSS. This occurs only after the eggs are released from the ovary (ovulation).
You may be more likely to get OHSS if:
OHSS rarely occurs in women who only take fertility drugs by mouth.
OHSS affects 3% to 6% of women who go through in vitro fertilization (IVF).
Other risk factors for OHSS include:
The symptoms of OHSS can range from mild to severe. Most women with the condition have mild symptoms such as:
In rare cases, women can have more serious symptoms, including:
If you have a severe case of OHSS, your health care provider will need to monitor your symptoms carefully. You may be admitted to the hospital.
Your weight and the size of your belly area (abdomen) will be measured. Tests that may be done include:
Mild cases of OHSS usually don't need to be treated. The condition may actually be associated with a greater chance of becoming pregnant.
The following steps can help you ease your discomfort:
You should weigh yourself each day to make sure you are not putting on too much weight (2 or more pounds or about 1 kilogram or more a day).
If your provider diagnoses severe OHSS before transferring embryos in an IVF, they may decide to cancel the embryo transfer. The embryos are frozen and they wait for OHSS to resolve before scheduling a frozen embryo transfer cycle.
In the rare case that you develop severe OHSS, you will probably need to go to a hospital. The provider will give you fluids through a vein (intravenous fluids). They will also remove fluids that have collected in your body, and monitor your condition.
Most mild cases of OHSS will go away on their own after menstruation starts. If you have a more severe case, it can take several days for symptoms to improve.
If you become pregnant during OHSS, the symptoms may get worse and can take weeks to go away.
In rare cases, OHSS can lead to fatal complications. These can include:
Call your provider if you experience any of the following symptoms:
If you are getting injections of fertility medicines, you will need to have regular blood tests and pelvic ultrasounds to make sure that your ovaries aren't over-responding.
Catherino WH. Reproductive endocrinology and infertility. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier Saunders; 2020:chap 223.
Fauser BCJM. Medical approaches to ovarian stimulation for infertility. In: Strauss JF, Barbieri RL, eds.Yen & Jaffe's Reproductive Endocrinology. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 30.
Lobo RA. Infertility: etiology, diagnostic evaluation, management, prognosis. In: Gershenson DM, Lentz GM, Valea FA, Lobo RA, eds. Comprehensive Gynecology. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 40.BACK TO TOP
Review Date: 7/13/2021
Reviewed By: John D. Jacobson, MD, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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