Whether to use the same ovarian stimulation protocol or change it after a failed in vitro fertilization cycle is still a controversial issue. In this study we aimed to investigate the effect of changing the stimulation protocol in the sequental cycle of the same patient population on intracytoplasmic sperm injection (ICSI) outcomes.

This retrospective study included two sequental fresh ICSI cycles of 941 infertile women attended in a period of one year. Group A was composed of patients who failed to have clinical pregnancy with a GnRH agonist and group B was composed of patients who failed to have clinical pregnancy with a GnRH antagonist protocol cycle. In both groups the study group was composed of patients whose stimulation protocol was changed in the sequential cycle and the control group was composed of patients who proceeded with the same stimulation protocol. The clinical pregnancy and live birth rates were primary outcomes.

In group A, the clinical pregnancy rates were comparable between the study and the control groups, but the live birth rate was higher in the study group (p=0.03). In group B, there was no difference in terms of clinical pregnancy and live birth rates between the study and control groups (p=0.740 and p=0.842 respectively).

Changing the ovarian stimulation protocol after a failed ICSI cycle downregulated with a GnRH agonist increased the live birth rate. After a failed cycle stimulated with a GnRH antagonist protocol, protocol change did not have any impact on the clinical pregnancy and live birth rates.