All participants started with a combination of recombinant FSH 300 U and urinary Gn 150 U from the 2nd day of the cycle then the dose was adjusted according to the ovarian response evaluated by transvaginal ultrasound and serum E2. Delayed start~From day 6 of the cycle, follow up using transvaginal ultrasound was done either daily or on alternate days according to the ovarian response. Ultrasound follow up reported number and size of follicles in each ovary and the endometrial thickness and pattern. When the leading follicle reached 12 mm, GnRH antagonist was started using Cetrotide 0.25 subcutaneously daily till the day of triggering. Triggering was done when at least 3 follicles larger than 14 mm and at least one of them reached a mean diameter of 17 mm or more.~At the day of triggering, women were randomized into 2 groups. Group I (single trigger group) that included 80 women who received triggering in the form of 10,000 IU of HCG intramuscular injection. Group II (Dual trigger group) that included 80 women who received triggering in the form of 10,000 IU of HCG intramuscular injection in addition to GnRH agonist triptorelin 0.2 mg subcutaneously.~Ovum pickup was done 34 hours after triggering under the guidance of transvaginal ultrasound.~ISM1 culture medium was used for oocyte collection and embryo culture. Transabdominal ultrasound guided embryo transfer was done 3 days after oocyte retrieval using Labotect semirigid catheter by the same expert operator~Cycle cancellation was done if day 9 folliculometry revealed less than 2 mature follicles, no oocytes were retrieved or if fertilization failed~Luteal phase support was started in all women on the day of oocyte retrieval and continued till the day of serum β-hCG assessment (done 14 days after ET) through administration of 400 mg of natural Progesterone twice daily per vagina . In women with +ve serum β-hCG (> 5 mIU/ml), transvaginal ultrasound evaluation was done 4 weeks after ET to confirm the presence and number of intrauterine gestational sacs.
All participants started with a combination of recombinant FSH 300 U and urinary Gn 150 U from the 2nd day of the cycle then the dose was adjusted according to the ovarian response~From day 6 of the cycle, follow up using transvaginal ultrasound was done either daily or on alternate days according to the ovarian response. When the leading follicle reached 12 mm, GnRH antagonist was started using Cetrotide 0.25 subcutaneously daily till the day of triggering. Triggering was done when at least 3 follicles larger than 14 mm and at least one of them reached a mean diameter of 17 mm or more.~At the day of triggering, women were randomized into 2 groups. Group I (single trigger group) that included 80 women who received triggering in the form of 10,000 IU of HCG intramuscular injection. Group II (Dual trigger group) that included 80 women who received triggering in the form of 10,000 IU of HCG intramuscular injection in addition to GnRH agonist triptorelin 0.2 mg subcutaneously.~Ovum pickup was done 34 hours after triggering under the guidance of transvaginal ultrasound.~ISM1 culture medium was used for oocyte collection and embryo culture. Transabdominal ultrasound guided embryo transfer was done 3 days after oocyte retrieval using Labotect semirigid catheter by the same expert operator~Cycle cancellation was done if day 9 folliculometry revealed less than 2 mature follicles, no oocytes were retrieved or if fertilization failed~Luteal phase support was started in all women on the day of oocyte retrieval and continued till the day of serum β-hCG assessment (done 14 days after ET) through administration of 400 mg of natural Progesterone twice daily per vagina . In women with +ve serum β-hCG (> 5 mIU/ml), transvaginal ultrasound evaluation was done 4 weeks after ET to confirm the presence and number of intrauterine gestational sacs.