Suboptimal response to GnRH agonist trigger: causes and practical management

Purpose of review GnRH agonist products are used extensively worldwide to trigger ovulation and final oocyte maturation in in vitro fertilization cycles. The purpose of this article is to outline possible causes for a suboptimal response to the GnRH agonist trigger. Recent findings Risk factors for such a suboptimal response include prolonged hormonal contraceptive use, previous GnRHa-induced pituitary downregulation, a hypogonadotropic/hypogonadal condition, patient error, environmental conditions that may damage the GnRHa product used, GnRH and luteinizing hormone (LH) receptors polymorphisms, low baseline LH and low endogenous serum LH levels on trigger day as well as low BMI. The induction of an adequate LH surge can be ascertained by an LH urine test 12 h post trigger. In most cases, GnRHa trigger elicits effective LH+follicle stimulating hormone surges, resulting in mature, fertilizable oocytes. Clinical awareness to conditions that may predispose to a suboptimal response to the GnRHa trigger may prevent failed oocyte retrial.