FAQs OHSS

Ovarian hyperstimulation syndrome (OHSS) is a complication of IVF treatment where the ovaries become very large and fluid collects in the abdomen and rarely around the lungs and heart.

Around a quarter of patients may develop mild OHSS.  One to three in a hundred patients will develop moderate, severe or critical OHSS.

The risk of OHSS is increased in women with polycystic ovary syndrome and younger women.

Mild OHSS gives symptoms of bloating and mild abdominal discomfort.

Moderate OHSS has symptoms of breathlessness, bloating and mild to moderate abdominal discomfort associated with nausea and sometimes vomiting or diarrhoea.  Women would produce less urine than normal.

Severe OHSS has symptoms of significant bloating and the tummy may feel very tight.  Women may also have shortness of breath or difficulty in taking a deep breath.  They may feel very dehydrated and thirsty, pass a small amount of  dark coloured urine.  Very rarely women may develop pain in a leg or pain on breathing which may indicate a clot in the leg or the lungs.

Call our reception team on 01392 40 5051, or email the specialist fertility nurses, via, rduh.fertilityexeter@nhs.net. Mark your email with ‘High Importance’ and put ‘OHSS’ as the subject title.

If you develop symptoms that you are worried about out of hours or at a weekend, please contact the gynaecology nurses on Wynard Ward in Wonford Hospital through switchboard 01392 411611. They may be able to give advice or they will speak to the on-call doctor. You may be asked to attend Wynard Ward, or a gynaecology ward at your local hospital if you live in North or South Devon, Cornwall or Somerset. If you can’t get through to Wynard ward call NHS 111, your GP or attend your local Emergency department (ED)

It is diagnosed on symptoms and the results of some investigations. You will have your weight and girth (waist measurement) taken and observations of your pulse, temperature and blood pressure.

An ultrasound scan is usually done to measure the size of your ovaries and to check for any fluid in your abdomen.

Bloods tests are done to measure kidney function and your blood count to see if your blood is becoming concentrated.

Sometimes a scan or X ray of the chest is needed.

Mild OHSS is treated at home. You will be advised to keep your fluid intake up and to take simple painkillers such as paracetamol but to avoid non-steroidal drugs such as ibuprofen.

Moderate OHSS can also be treated at home. You may need a brief stay in hospital to have fluids via a drip into your vein and you may also be given some anti-sickness medication.

Severe OHSS usually requires a stay in hospital. In addition to the measures above, you may need to have the fluid from your abdomen drained through a needle or plastic tubes placed under ultrasound control. This is called a paracentesis.

If you are staying in hospital you will be given blood thinning injections and compression socks to prevent deep vein thrombosis.  You may also require to take blood thinning injections at home following the discharge from hospital.

Most cases of OHSS resolve in 7 to 10 days but it can last for a few weeks if the woman is pregnant as the pregnancy hormone may make the OHSS worse.

There is advice about OHSS on the Royal College of Obstetricians and Gynaecologist’s website and there is also information on the HFEA website www.hfea.gov.uk

You can also get more information from the Fertility Exeter team by contacting us on 01392 40 5051 or email rduh.fertilityexeter@nhs.net.