The dynamics of endometrial growth and the triple layer appearance in three different controlled ovarian hyperstimulation protocols and their influence on IVF outcomes

The impact of endometrial growth to the triple layer, endometrial thickness, and echogenicity on IVF outcomes was investigated in the study. A retrospective analysis of 583 ICSI patients was conducted: 385 with a long GnRH agonist protocol, 114 with a short GnRH agonist, and 84 with a GnRH antagonist protocol. The progression of endometrial growth to the appearance of the triple layer, endometrial thickness, and echogenicity was compared between protocols. At least one high quality blastocyst was transferred in a double embryo transfer. The time of the appearance of the endometrial triple layer was statistically significant for the pregnancy rate only in the GnRH antagonist protocol. The endometrial thickness on the day of the appearance of the triple layer had a statistically significant influence on the pregnancy rate in the GnRH antagonist and in the long GnRH agonist protocols. The highest pregnancy rate for the long GnRH agonist and the GnRH antagonist protocols was observed when the endometrium thickness was 12-13 mm (61.6% and 58.8%, respectively). The endometrial echogenicity had a significant influence on the pregnancy rate only in the long GnRH agonist protocol. Endometrial features could be helpful parameters in IVF outcomes in particular controlled ovarian hyperstimulation protocols.