PREVENTION OF SEVERE OVARIAN HYPERSTIMULATION BY COASTING

Objective: To evaluate the efficiency of withholding gonadotropins and deferring the administration of hCG until E-2 levels start dropping ( coasting) in the prevention of ovarian hyperstimulation syndrome (OHSS ) in a high-risk population. Design: Retrospective case-control study. Setting: In vitro fertilization program at a university center. Patie nt(s): The case group consisted of 120 women undergoing ovarian stimul ation for IVF who were considered to be at risk for ovarian hyperstimu lation (serum E-2 levels >2,500 pg/mL or >20 follicles at the time of hCG administration). Intervention(s): Gonadotropin administration was withheld when serum E-2 levels exceeded 2,500 pg/mL, and hCG administr ation was delayed until E-2 levels dropped below 2,500 pg/mL. Outcomes were compared with those from 120 matched patients in whom serum E-2 levels and the number of follicles at the time of hCG administration w ere comparable to those at the beginning of coasting (control group). Main Outcome Measure(s): Incidence of moderate and severe OHSS. The nu mber of oocytes retrieved and pregnancy rate (PR) were compared in bot h groups. Result(s): Coasting decreased the incidence of moderate and severe OHSS. The odds ratio of severe OHSS in the coasting group was 0 .11 (95% confidence interval 0.01-0.86). Although the number of oocyte s was significantly lower in the coasting group (19.7 +/- 0.6 versus 2 2.1 +/- 0.6), coasting did not affect the PR (37.5% versus 36.7%). Con clusion(s): Our study indicates that coasting is an efficient method f or reducing the incidence and severity of OHSS without compromising th e PR. (Fertil Steril(R) 1998;70:847-50. (C) 1998 by American Society f or Reproductive Medicine.).