Background: Ovarian hyperstimulation syndrome (OHSS) is an important and dangerous aspect of assisted reproduction techniques. Although elective cryopreservation of all embryos can prevent pregnancy-induced late OHSS, it cannot prevent early OHSS, which is induced by hCG administration.
Methods: We undertook this trial to assess the efficacy with which the combined oral administration of angiotensin-converting enzyme inhibitor (ACEI) and angiotensin II receptor blocker (ARB) could prevent early OHSS in IVF patients at very high risk for this syndrome. Four women, who had serum estradiol concentration > or =8000 pg/ml on the day of hCG injection, were treated with the combination of the ACEI alacepril and the ARB candesartan cilexetil for 8 days starting the day after oocyte retrieval. Embryos were cryopreserved and embryo transfer was postponed until later cycles.
Results: Despite the extremely enlarged ovaries, no ascites was accumulated in any of the cases. Haematocrit (34.1 +/- 1.0) and serum albumin concentration (4.1 +/- 0.2 g/dl) were normal throughout the treatment period. These patients showed elevated plasma renin and angiotensin II concentration before the treatment.
Conclusions: The dual renin-angiotensin blockade therapy used here would be worth exploring further in a study with more patients and a prospective, randomized design.