study the effect of aromataze inhibitor induction together with short stimulation protocol by gonadotrphin releasing hormon antagonist in cases that expected to be poor responder before ICSI

This is a prospective randomized case control study will be conducted in Maternity hospital IVF unite Minia University after being approved by local ethical committee of obstetrics and gynecology department faculty of medicine, all study details will be explained to patients and informed consent will be obtained before inclusion in the study . enrolled patients will be randomized into two groups using simple randomization by sealed opaque envelops contain serial computer generated numbers Control group will receive HMG 300 IU daily start at first day of menses with follow up by trans vaginal ultrasound (TVUS ) when at least three follicles reach 14mm diameter GnRh antagonist given 0.1 ml continue follow up when at least three follicles reach 17mm in diameter ovum pickup will done under TVUS guide if less than three follicles cycle will be cancelled . Study group will receive same management plus letrozole 2.5mg daily start at the first day of menses for 5 days and continue with same protocol