Abstract: Objective: To investigate the pregnancy outcome of those IVF patients with high E2 level after the repeated pituitary down-regulation with the long protocol. Methods：It is a retrospective study. Six IVF patients whose E2 levels did not match the criteria after the repeated pituitary down-regulation with long protocol were analyzed, from January 2012 to August 2014. Results：Four patients were treated with direct COH, and two patients had clinical pregnancy. One patient had clinical pregnancy after changing to the mini-stimulation protocol. One patient had clinical pregnancy after using LE and COH. Conclusions：Those IVF patients with E2 level not reaching the criteria after the repeated pituitary down-regulation could obtain ideal pregnancy outcome through regulating their protocols of induced ovulation.

Key words: Pituitary gland, Estrogens, Reproductive techniques, assisted, Ovulation induction, Pregnancy outcome