Elective cryopreservation of all embryos in women at risk of developing ovarian hyperstimulation syndrome may not prevent the condition but reduces the live birth rate

Objective: Our goal was to evaluate the use of elective cryopreservation of all embryos to prevent the development of ovarian hyperstimulation syndrome in patients at risk while undergoing in vitro fertilization treatment. Design: We analyzed 117 treatment cycles in which the serum E(2) concentration on the day of hCG administration was >10,000 pM and in whom greater than or equal to 15 oocytes were retrieved at ultrasound-directed follicle aspiration. The incidence of ovarian hyperstimulation syndrome, pregnancy, and live birth in 65 patients who had elective cryopreservation of all embryos and 52 patients who had fresh embryo transfer were compared. Independent t test and chi-square test (with Yates' correction) was used as appropriate. Results: The clinical pregnancy (35 vs 17%; P < 0.03) and the live birth (27 vs 12%; P < 0.05) rates in patients receiving fresh embryo transfer was significantly higher than in those who had elective cryopreservation of all embryos, The incidence of moderate and severe ovarian hyperstimulation syndrome was similar in both groups (3.8 and 6.2%). Conclusions: Elective cryopreservation of all embryos does not reliably protect against the development of ovarian hyperstimulation syndrome but may reduce the clinical pregnancy and live birth rate.