Luteinizing hormone-releasing hormone agonists for ovarian stimulation in assisted reproduction.

Although the use of luteinizing hormone-releasing hormone (LHRH) agonists and human menopausal gonadotropin (hMG) for ovarian stimulation in assisted reproduction has gained widespread popularity, a number of major issues regarding their use remain unresolved. Some of these issues are examined in the light of recent developments. The routine use of LHRH agonists produces significantly higher pregnancy and livebirth rates compared with conventional methods of ovarian stimulation. A number of prospective, randomized studies have shown that the long protocol of LHRH agonist administration is superior to the short and ultrashort protocols, and it appears that early follicular phase initiation of the long protocol may be particularly beneficial. Another major advantage of the long protocol of LHRH agonist administration is that, with its use, precise timing of human chorionic gonadotropin (hCG) administration is not important. It would, therefore, appear that the routine use of LHRH agonists has both medical as well as practical advantages.