Short answer: OHSS (ovarian hyperstimulation syndrome) is an over-response of the ovaries to fertility injections, where fluid leaks into the belly and sometimes the chest. The Gonal-f and Follistim AQ labels name severe pelvic pain, nausea, vomiting and weight gain as early warning signs. It can develop quickly after the injections stop and peak about 7 to 10 days after treatment. In label trials it occurred in about 5% to 8% of women.
The Gonal-f RFF Redi-ject label (section 5.3) says OHSS is distinct from simple ovarian enlargement and may progress rapidly to a serious medical event. It is marked by a sharp increase in how leaky blood vessels are, which can let fluid build up quickly in the abdomen, the chest and, potentially, around the heart. The Follistim AQ (section 5.2) and Menopur (section 5.2) labels describe it the same way.
The Gonal-f patient leaflet puts it in plain words: OHSS can happen when the ovaries produce too many eggs, can cause fluid to suddenly build up in the stomach area, chest and heart, can cause blood clots, and in rare cases has caused death.
The labels name severe pelvic pain, nausea, vomiting and weight gain as early warning signs. Other reported features include abdominal pain and swelling, diarrhea, severe ovarian enlargement, shortness of breath and passing less urine.
That list is from the Gonal-f leaflet, which says to stop using the medicine and call your healthcare provider right away if they appear. It also says OHSS may happen after you stop the injections.
The Gonal-f label says OHSS occurs after the gonadotropin is stopped and can develop rapidly, reaching its maximum about 7 to 10 days after treatment. It usually resolves on its own with the start of a period. Cases are more common, more severe and last longer if pregnancy occurs, so the label says women should be watched for OHSS for at least two weeks after the hCG trigger shot.
The labels say that if OHSS seems to be developing before the trigger, hCG must be withheld, and the Follistim AQ label says hCG should not be given if the ovaries are abnormally enlarged on the last day of treatment. That is why clinics track follicles by ultrasound and estradiol blood tests during a cycle; see female fertility medicines.
| Medicine | Section | Rate |
|---|---|---|
| Gonal-f RFF | 5.3 | 7.2% of 83 women (ovulation induction); 4.6% of 237 women (assisted reproduction) |
| Follistim / Follistim AQ | 5.2 | 7.6% of 105 women (ovulation induction); 6.4% of 751 women (IVF or ICSI) |
| Menopur | 5.2 | 7.2% of 373 women (IVF trial) |
These rates mix mild and severe cases and are not comparable across products, since the trials differed. If serious OHSS occurs, the Gonal-f label says to stop gonadotropins including hCG and consider whether hospital care is needed. Dose Track can log each injection and the trigger time, and notes on weight and symptoms on the days after, which is the window the labels describe.
Read more on Dose Track: Female fertility medicines · Gonal-f side effects · Menopur side effects · Menopur vs Gonal-f · Cetrotide vs ganirelix