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Ovarian HyperStimulation Syndrome

This is probably the most serious side effect of in vitro fertilisation treatment. It is related to the drug stimulation that you receive rather than the in vitro fertilisation itself and the syndrome can occur in women receiving these drugs for other reasons. As the ovaries are stimulated more than would normally be the case in a natural cycle, they always are larger than normal and contain fluid filled structures (follicles), which contain the eggs. This occurs in all women having IVF treatment and is not a cause for concern. In approximately one woman in a hundred, the more serious form of Ovarian HyperStimulation Syndrome develops. Here, the ovaries become greatly enlarged and contain large cysts. These cysts produce copious quantities of fluid, which is released into the tummy cavity. The fluid is rich in minerals and protein. The symptoms of severe Ovarian HyperStimulation Syndrome include abdominal pain, a marked degree of abdominal swelling, shortness of breath, nausea and possibly vomiting, and a reduction in urine output. In the presence of severe symptoms, hospitalisation may be necessary. This enables the fluid minerals and protein to be replaced and corrective measures put in place to prevent further complications. Due to the seriousness of the problem, prevention is better than cure. Although it is not possible to be certain about which patients will develop Ovarian HyperStimulation Syndrome, those with the ovarian hormone abnormality called polycystic ovaries are known to be more at risk. This will be assessed at the time of your preliminary consultation prior to starting IVF treatment.

Patients who respond to the drug treatment by producing very many eggs, particularly if they are experiencing lower abdominal pain before the time of the egg collection are also at increased risk. In these circumstances, the treatment cycle may be cancelled before the late night ovitrelle injection or, if the egg collection is performed, all of the embryos may be frozen and none transferred immediately. This should reduce the chance of the serious form of hyperstimulation syndrome from developing. When you are undergoing your treatment cycle, you will be issued with an information sheet on Ovarian HyperStimulation Syndrome with details of who to contact if you are concerned.