The aim of study is to evaluate the results of three different protocols for prevention of premature ovulation in ovarian stimulation cycles. All patients that undergo IVF cycles are randomly divided into three groups. The first group is cetrorelix, the second group is medroxyprogesterone acetate and the third group is dydrogesterone.

Approximately %10-15 of couples of reproductive age have infertility issues. Ovulation induction and in vitro fertilization (IVF) are the main treatments for infertility. With ovarian stimulation (OS), the efficiency of IVF has been increased by collecting more than one oocytes and thus providing more embryos. Multifollicular growth in OS may cause an increase in sex steroids and an early LH peak, thus premature ovulation. Pituitary suppression with certain drugs has been used to prevent premature ovulation.. Among these drugs, it has been observed that GnRH agonists can cause down-regulation, hypo-estrogenic symptoms, ovarian cyst formation and Ovarian Hyperstimulation Syndrome (OHSS), while antagonists may have side effects such as low oocyte count and high cycle cancellation. The use of progesterone preparations as an alternative to these drugs recently gained ground.

Data including age, BMI, the duration of infertility, the type of infertility, antral follicle count, serum day 3 FSH level, Serum anti-Müllerian hormone level, total gonadotropin dose, stimulation time, pituitary suppression starting day, duration of pituitary suppression, premature ovulation, number of total oocyte count, the number of total M2, the number of PN , the number of Day 5 blast, number of transferred embryos, endometrial thickness on the day of transfer will be recorded. When the follicle size reaches 13-14 mm, patients will be randomized into 3 groups. Group 1 (Cetrorelix: n=99, 0.25 mg/day subcutaneously), Group 2 (Medroxyprogesterone Acetate: n=99, 2x5mg/day orally) and Group 3 (Dydrogesterone: n=99, 3x10 mg/day orally). Human chorionic gonadotropin (hCG) will be used for trigger when at least 2 follicles' diameter reaches 17-18mm for ovulation. Thirty-six hours after the hCG injection, the patient's oocytes will be collected. During 2-5 days of embryo culture, embryo quality will be determined according to D.Gardner criteria (1999). Embryos will be frozen as blast on the 5th day and transferred to the frozen cycle to be planned within the next month. Clinical pregnancy rates will be recorded by performing a blood test for on the 12th day after the procedure.

The aim of this study is to evaluate the results of three different protocols for prevention of premature ovulation in ovarian stimulation cycles. All patients undergo IVF cycles are randomly divided in to three groups. The first group is cetrorelix, the second group is medroxyprogesterone acetate and the third group is dydrogesterone.

Inclusion Criteria:

• Women aged 20-38 years who applied to the infertility clinic
• BMI<25 kg/m2
• AMH>1 ng/mL

Exclusion Criteria:

• Adenomyosis
• Endometriosis
• Untreated uterine pathology
• Hormonal therapy in the last 3 months
• Contraindication for ovulation stimulation
• BMI>25 kg/m2
• AMH<1 ng/mL