What is Ovarian Hyperstimulation Syndrome (OHSS)?

If you’re preparing to be an egg donor – or even just considering it – well, that’s fantastic! Egg donors are quite literally giving the gift of life to a person or a couple who is otherwise unable to start their family. 

By now, you might have done some research about egg donation and the risks, and it’s probably raised a few questions about what you might be in for. 

The good news is that egg donation is a relatively safe procedure, but there are a few risks you should know about, like the side effects of fertility drugs and the possibility of Ovarian Hyperstimulation Syndrome, or OHSS. 

What is Ovarian Hyperstimulation Syndrome (OHSS)?

OHSS is a temporary condition that may occur in women who are undergoing fertility treatment to induce ovulation. Fertility treatment is a major part of the egg donation process, so it pays to know about OHSS. 

As an egg donor, you will have to undergo ovulation induction via hormonal treatment. The egg donor medication protocol involves being injected with human gonadotropin and follicle-stimulating hormones, which encourage your ovarian follicles to produce multiple eggs faster than they normally do. Although women naturally release one egg a month, these hormonal injections allow a large number of eggs to develop and mature at the same time. Once your eggs are mature and ready for retrieval, your fertility doctor will schedule the procedure for egg retrieval. 

In most cases, hormonal treatment and egg retrieval go ahead without a hitch. In fact, studies have shown that the risk of OHSS is rare. Less than 5% of all women who receive IVF treatments may develop OHSS and most cases are mild.

A study published in the medical journal Human Fertility reported that if an egg donor develops fewer than 20 follicles, she can be assured that her risk of OHSS is very small – less than 0.1%. If she develops more than 20 follicles, her risk of hospital admission due to OHSS is slightly higher, but still less than 15%. 

Abnormalities can take some time to be detected, so if you develop more than 20 follicles, your clinic will actively monitor you for the first week after your eggs are retrieved.  

What causes OHSS?

OHSS occurs when your body’s hormone levels surge very quickly due to the medications you’re taking, especially gonadotropins. The hormones may cause your ovaries to swell as a larger number of follicles than normal start to grow. Fluid then can then leak through the impaired blood vessels both within and outside the ovaries and into your abdomen, causing edema (swelling). 

What are the symptoms of OHSS?

The main symptoms of OHSS are bloating, nausea, and a swollen tummy. 

Other symptoms may include:

• Diarrhea
• Intense abdominal pain
• Rapid weight gain
• Persistent nausea
• Shortness of breath
• An enlarged abdomen
• Decreased urination

OHSS can range from mild to severe, as described below:

Mild OHSS: some abdominal swelling, discomfort, and nausea.

Moderate OHSS: Swelling is worse due to fluid building up in the abdomen. This may be accompanied by abdominal pain, nausea, and vomiting.

Severe OHSS: Increased swelling in the abdomen, along with symptoms of dehydration. You may be extremely thirsty and pass only small amounts of dark urine. A buildup of fluid in the chest may make breathing difficult, which is obviously a sign that you need urgent medical attention. 

In very rare cases, OHSS can lead to a blood clot forming in the leg or the lungs. This is accompanied by swelling and tenderness in the area or chest pain and breathlessness. This should be treated as an emergency. 

What are my risks of OHSS as an Egg Donor?

Mild OHSS is most often related to IVF treatment, which is why egg donors need to be aware of the signs and symptoms. Mild OHSS affects up to 5% of women who undergo IVF treatment, with only 1% of women developing moderate or severe OHSS. 

Your risks of developing OHSS are higher if:

• You have PCOS (polycystic ovaries)
• You’re under 30 years old
• You have a very high estrogen level during fertility treatments
• You’ve had OHSS before
• You get pregnant during the same IVF cycle as your symptoms appear, especially if you are having twins or triplets. 

What should I do if I have OHSS symptoms after my egg donation?

If you experience any of the symptoms described above, you should consult your doctor as soon as possible. Even if your symptoms are only mild, it’s better to be safe than sorry. Explain your symptoms and their severity as accurately as you can so that your medical professional can make a plan for preventing a more serious situation. 

Because it’s almost impossible to know your risk of developing OHSS, every egg donor needs to be aware of the signs and symptoms. Your medical professional will be monitoring you to make sure that everything is going well. 

How long will I be affected by OHSS?

OHSS is a temporary condition, and a mild case of OHSS should resolve itself within seven to ten days. Your OHSS should improve by the time your next menstrual cycle begins. 

How is OHSS treated?

The good news is that most cases of OHSS after egg donation are mild and will go away on their own. It’s important to drink plenty of electrolyte-rich fluids throughout the day and avoid vigorous physical activity. It’s safe to take acetaminophen for pain, but try to avoid anti-inflammatory drugs like aspirin or ibuprofen because they can place an extra burden on your kidneys. 

If your symptoms become severe, hospitalization may be necessary. If this happens, you may have to wear support stockings and take heparin injections to reduce the risk of thrombosis. 

Remember, the risks of developing OHSS are low, and the condition is temporary. Even if you do develop symptoms, you will be immediately looked after by your medical professionals and the team at FSC.

If you have any more questions or concerns, send us a message. We’re always here to help!