Different routes of progesterone administration for sustaining implantation in in vitro fertilisation patients: impact on pregnancy and live birth rates

INTERVENTION: All the patients are going to have a mild ovarian stimulation protocol: rFSH will be started at a dose of 75‐150 IU on the base of AMH level. GnRH antagonist (0.25 mg/day) will be administered when the leading follicle measures 14 mm. The FSH dose will be adjusted when necessary according to the follicular size and estradiol level. Final oocyte maturation will be induced by a dose of 10,000 IU of hCG. Recovered oocytes will be inseminated by standard IVF or intracytoplasmic sperm injection (ICSI). Up to three embryos will be transferred on day 3 after oocyte insemination. Randomization will be performed using a computer‐generated random assignment schedule for each patient. Sealed and numbered envelopes will be used to conceal the treatment allocation until randomization. On the day of oocyte recovery, the patients will be randomized into two groups: Group A will receive vaginal administration of capsules of micronized progesterone (800 mg/day) for luteal phase support; Group B will receive a combination of vaginal administration of a gel of micronized progesterone (90 mg/day) and oral dydrogesterone 10 mg twice a day for luteal phase support. The duration of the treatment is 14 ‐ 21 days; follow‐up will be around 9 months for each patient, from the established pregnancy to the delivery. CONDITION: Luteal phase supplementation in assisted reproduction ; Pregnancy and Childbirth PRIMARY OUTCOME: Clinical pregnancy measured using a blood test to evaluate the level of human chorionic gonadotropin (hCG), which indicates the eventual embryo implantation and pregnancy, 14 days after embryo replacement in the patient's uterus; SECONDARY OUTCOME: Embryo implantation rate measured using ultrasonography at 4 weeks following a positive hCG test to confirm the clinical pregnancy INCLUSION CRITERIA: 1. Infertility attributable to tubal factors, moderate endometriosis, male factor, or idiopathic infertility 2. Serum hormonal profile within the normal range (AMH >1 ng/ml) 3. Regular menstrual cycles 4. The presence of a normal uterine cavity 5. Body mass inde X(BMI) of 20–26 kg/m²