DRUG
mild stimulation protocol: oral Clomiphene Citrate
Group A (mild stimulation protocol) will receive oral Clomiphene Citrate (Clomid®) 150 mg/day for 5 days (starting on the 2nd of menses), followed by FSH/HMG (human menopausal gonadotropins) at a daily dose of 150-225 IU starting from the 6th day of the menstrual cycle. GnRH antagonist (Cetrotide®, Merck-Serono, Switzerland) 0.25 mg subcutaneously daily will be started once a dominant follicle becomes ≥14 mm until the day of final follicle maturation. Once 3 leading follicles reach 18mm in diameter, final follicle maturation will be triggered using HCG (Choriomon® 10,000 IU) in the presence of 14 or less pre-ovulatory follicles or GnRH agonist (Triptorelin-Gonapeptyl® 0.3mg single dose) in the presence of 15 or more follicles. The choice of the starting FSH/HMG daily dose will be tailored to BMI: 150 IU/d for BMI less than 25 and 225IU/d for BMI 25 and above.