Design:
This was a retrospective cross sectional study for 402 FET cycles which conducted between April 2018 and May 2019. All participants started endometrial preparation for FET with 6 mg/day oral estradiol for 13 days. When endometrium reached 8 mm or greater, patients were initiated on both micronized vaginal and oral P treatment. On FET day, serum level of E2 and P were assessed. Then, transfer of PGT euploid embryos was performed. 12 days later pregnancy test was assessed, and then 4 weeks after FET date ultrasound was scheduled to check the viability and the clinical pregnancy.