Ovarian Hyperstimulation Syndrome (OHSS)
What is OHSS?
As part of your IVF treatment we will be stimulating your ovaries to produce more than the one egg, which is what usually happens naturally every month. One of the risks associated with stimulation of the ovaries as part of superovulation fertility treatment is Ovarian Hyperstimulation Syndrome (OHSS).
OHSS is a rare condition that occurs when too many follicles grow and cause abdominal distension, discomfort, and nausea. In extreme cases (1-2%) fluid collects in the abdomen and chest cavity and can press on the lungs leading to a feeling of breathlessness. Hospitalisation may become necessary. It is potentially very serious and may become life threatening if not managed appropriately. However it can be treated successfully if detected early.
Who is at risk from OHSS?
Anyone having ovarian stimulation to increase the number of follicles and eggs is potentially at risk of OHSS, however it is usually those women who quickly develop many follicles (more than 20) in response to stimulation who are most at risk from severe OHSS. Since we monitor the development of your follicles from an early stage, we are likely to detect such cases early on and manage them before they present a more serious risk. For a very few women it may be considered unsafe to proceed to egg collection. The treatment cycle will be stopped early, and recommenced at a future date when safe to do so, using a lower dose of drugs.
In some cases symptoms do not become apparent until after egg collection; if these are assessed by a doctor as being potentially serious, then we would not perform an embryo transfer which could worsen the condition. But you would not lose your chance of becoming a parent as instead all your embryos would be frozen so that they could be transferred at a later date.
What are the symptoms of OHSS?
Symptoms include a distended abdomen with pain, nausea, vomiting, shortness of or inability to catch your breath, reducing urine output despite drinking plenty of fluid, and fainting.
What should I do if I think I have OHSS?
It is likely that you may experience some mild symptoms as most women undergoing treatment with fertility drugs do tend to experience some symptoms of OHSS. You can usually self-manage these with rest and a good daily fluid intake (about 2 litres of water, weak tea, diluted juice etc.) until your symptoms vanish. However, if you are at all concerned you should contact us.
During office hours you can contact us on the normal Bath Fertility Centre telephone number of 01761 434464.
If there is an emergency outside office hours, our answer phone will give a pager or mobile number where one of the medical team can be contacted. Alternatively you can contact your GP or go to the nearest hospital emergency department but if you do it is important that you mention you have undergone superovulation IVF treatment.