The overall objective: Comparison of effect of four different protocols for ovarian stimulation including: hFSH, rFSH, HMG, sequential use of hFSH & rFSH on quality of oocyte and embryo Specific goals: 1-Compare duration of stimulation 2-Compare number of follicles with large and medium size 3- Compare the serum estadiol level on hCG day 4- Compare number of retrieved oocytes 5- Compare the quality of oocytes ( MI, MII, GV ) 6-Compare the quality of embryos (grade 1 to grade 4) 7- Compare number of transferred embryos Material methods: The patients who refer to Dena hospital and mother and child infertility center are refered to Gynecologist ( in the center) according to inclusion and exclusion criteria, after taking informed permission. All the participants (160 persons) will be underwent down-regulation standard protocol with GnRH agonist (buserelin 0.4mg) , subcutaneously from day 21 of menstrual cycle. From day 2 of next cycle, after determination of desensitization (estradiol level less than 50 pg/ml, no follicle with 10 cm or more size, endometrial thickness less than 5mm) gonadotropins is started. The patients will be divided into four groups ,completely randomely and according to the numbered table. The first group(40 pt) will receive HP-HMG (menopur, ferring pharmaceuticals, Copenhagen Denmark) from day 2 to the hCG day. The second group(40 pt) will receive hFSH (Fostimon, IBSA, Geneva, Switzerland) from day 2 to the hCG day The third group(40 pt) will receive rFSH (Gonal-F, Sereno, Rome, Italy) from day 2 to the hCG day. The fourth group(40 pt) will receive hFSH (Fostimon, IBSA, Geneva, Switzerland) for six days and then continued with rFSH (Gonal-F, Sereno, Rome, Italy) to the hCG day. From the day 6, dosage of gonadotropins adjusted according to evaluation of stimulation with transvaginal sonography and serum estradiol, each 1-3 day Stimulation continued until there was at least two 17-18 mm follicles & some 14-16 mm follicles & appropriate estradiol level In the cases of ovary hyperstimulation that ovaries became grossly large , containing more than 15 follicles in medium ( >15mm) & large (>16mm) size, high level of estradiol (>3500pg/ml), counseled with the patients aboute the risk of OHSS , and evaluated for sign and symptoms of OHSS Management of these patients was done according to instructions in Guideline of Infertility center of Shiraz University of Medical Siences , based on serum estrsdiol level and size of follicles. When a group of follicles became mature, 10000 IU hCG (Gonasi HP, IBSA, Italy) was administered for final step of maturation 34-36 hours after hCG administration, oocyte retrieval was done under guide of transvaginal sonography and evaluated for maturation. Immature oocytes with germinal vesicle within them belongs to GV group Immature oocytes in methaphase I without germinal vesicle or polar body belongs to MI group. Mature oocytes in methaphase II with polar body in previtteline space belongs to MII group After fertilization , IVF or ICSI was done ( for each patient according to indication). Embryo scoring was done according to morphological features: Grade A: embryos with 8 blastomeres , equal size & without fragmentation Grade B: blastomers have equal size with mild to moderate fragmentation. Grade C: blastomers don’t have equal size with or without fragmentation. Grade D: blastomers with moderate to severe fragmentation , with or without equal size. 72 houres after fertilization, embryos transfered under guide of sonography. Pregnancy supported by intramuscular progesterone (50 mg/ml). Chemical pregnancy confirmed with rise of ß-hCG at day 12 ( after embryo transfer), and clinical pregnancy by detecting gestational sac in 6th week sonography It should be mentioned that this study was assessor blind. (Intervention/Control): The first group(40 pt) received HP-HMG (menopur, ferring pharmaceuticals, Copenhagen Denmark) from day 2 to the hCG day. The second group(40 pt) received hFSH (Fostimon, IBSA, Geneva, Switzerland) from day 2 to the hCG day. The third group(40 pt) received rFSH (Gonal-F, Sereno, Rome, Italy) from day 2 to the hCG day The fourth group(40 pt) received hFSH (Fostimon, IBSA, Geneva, Switzerland) for six days and then continued with rFSH (Gonal-F, Sereno, Rome, Italy) to the hCG day Primary outcome measure : quality and number of ovum and emberyo have received in each cycle