OVARIAN HYPERSTIMULATION SYNDROME (OHSS)
OHSS is characterized by enlarged ovaries, pelvic pressure/fullness sensation and fluid accumulation in the abdomen following gonadotropin treatment. While most cases are mild (10-20% of gonadotropin cycles), severe cases can occur as well (1% of cycles). In the mild form, some discomfort is felt by the patients, which resolves on its own without any complications. In the severe form, marked enlargement of ovaries and fluid accumulation in the abdomen can result in difficulty in breathing, intolerable abdominal pain, kidney dysfunction, blood clot formation, ovarian torsion (twisting of the ovary) and even death (although extremely rarely). In severe cases, hospitalization may be required for close monitoring and drainage of fluid from the abdomen by a procedure called paracentesis, which may be necessary to improve symptoms.
OHSS is self-limiting with supportive therapy and usually resolves in 1-2 weeks. When a pregnancy forms in the presence of OHSS, the syndrome is more severe and lasts longer compared to a cycle that does not result in a pregnancy. Patients at risk should be identified early and monitored closely to avoid the severe form.
Some of the prevention and treatment modalities include delaying the administration of HCG injection until estradiol levels fall to a certain threshold (coasting), freezing all embryos and transferring them in a subsequent cycle and administration of albumin and intravenous fluids. More recent modalities include the use of metformin in patients with PCOS, using Lupron for ovulation trigger, administration of GnRH antagonists, use of aspirin and a steroid as well as a medication called cabergoline. Using such interventions, OHSS has become a rare complication in the practice of IVF.
At LA IVF, severe OHSS is extremely rare due to specific protocol design for each individual case, use of the above medications and close monitoring of response to gonadotropin treatment.
