GnRH Agonist Addition to Routine Luteal Phase Support in Assisted Reproductive Technology

Luteal phase defect is a frequent problem in assisted reproductive technology cycles most probably as a result of supraphysiological steroid levels that inhibit corpus luteum functions. Luteal phase supports essential to counter luteal phase defect to ensure an optimal implantation, pregnancy and delivery rate. Today, the routine luteal phase support is established by progesterone administration. Recently, GnRH agonists have been evaluated to increase the success rates of routine luteal phase support. The possible mechanisms with GnRH agonists for luteal phase support include stimulation of corpus luteum by pituitary LH secretion, activation of local GnRH receptors on endometrium, and possibly effecting trophectoderm cells. Recent data demonstrated that implantation rates may increase with adjunctive use of GnRH agonists. However definitive effect of GnRH agonists as an additional agent to support luteal phase should be clarified in large scale studies in both fresh agonistic and antagonistic GnRH analog cycles and frozen thawed cycles.