Induction of pre-ovulatory luteinizing hormone surge by gonadotrophin-releasing hormone agonist for women at risk for developing the ovarian hyperstimulation syndrome.

Ovarian hyperstimulation syndrome (OHSS) is a major risk in patients undergoing ovulation induction protocols. Withholding injection of human chorionic gonadotrophin (HCG) may prevent the development of OHSS, but can also result in failure to ovulate and conceive. We have used a gonadotrophin-releasing hormone agonist (GnRHa) as an alternative to HCG in women not undergoing in-vitro fertilization in an attempt to prevent OHSS. The study included 12 cycles in 12 women scheduled for ovulation induction with human menopausal gonadotrophin (HMG) who were at risk of developing OHSS (oestradiol > 3500 pg/ml, number of follicles > 20). GnRHa was injected to induce the pre-ovulatory, luteinizing hormone surge which triggers follicular maturation. Progesterone was administered for luteal support. Six pregnancies were achieved, and none of the 12 women developed OHSS. Since the pregnancy rate in this study was acceptable, we can recommend the use of GnRHa instead of HCG in any case at risk of developing OHSS.