Is there a difference between outcomes of the spontaneous natural cycle and hormone replacement treatment in frozen-thawed human embryo transfer?
Turgut Aydın (TR), (TR)
[Aydın] Kayseri Acıbadem Hospital, []
Objective: We sought to evaluate and compare the implantation, pregnancy and live birth rates following frozen-thawed embryo transfer (FET) in a natural and hormonal control cycle. Methods: This single-center, retrospective study was implemented in the IVF unit. Patient(s): A total of 244 women planning to receive FET in the IVF unit were recruited in this trial. Two groups were constituted: Group 1 consisted of 101 women who underwent FET after spontaneous ovulation; while 143 women had FET after endometrial preparation with hormone replacement therapy. Intervention(s): Patients in the natural cycle group were invited to the clinic 18 days prior to the next expected period of the determination of serum levels of E2 and LH until surge of LH. FET was performed on the 3rd day after surge of LH. Hormone replacement treatment in Group 2 consisted of administration of estradiol tb twice daily, for eight days starting from the 3rd day of the cycle. The dose of estrofem tb was increased to 3 times a day for at least four days. Subsequent to the achievement of an endometrial thickness of 7 mm, maintenance dose for estrofem was shifted to 2 tablets daily, and a vaginal gel containing 90 mg of progesterone was added to the regimen. Transfer of blastocysts was performed on the 6th day, and the same treatment was continued until 10th week if pregnancy was confirmed clinically. Main Outcome Measure(s): Rates of implantation, clinical pregnancy, and live birth were compared between two groups. Result(s): There was no difference between 2 groups regarding rates of clinical pregnancy (p=0.13), implantation (p=0.19) and live birth (p=0.26). Conclusions: We suggest that FET in natural cycle is a comfortable method that provides satisfactory therapeutic outcomes as well as reduction of costs and avoidance of side effects linked with hormone replacement therapy.