title: Hormonal replacement treatment improves clinical pregnancy in frozen-thawed embryos transfer cycles: a retrospective cohort study.
abstract: This study aimed to assess frozen-thawed embryo transfer (FET) outcomes in natural, hormone replacement treatment (HRT) and semi-HRT cycles. This was a retrospective cohort study of 5414 cycles of patients in an academic hospital. Patients were grouped as 2216 natural cycles, 1180 semi-HRT cycles, and 2018 HRT cycles. Primary outcome measures were implantation rate, clinical pregnancy rate and live birth rate. Other parameters, such as peak endometria-thickness, were also analyzed. Patients undergoing FET with HRT obtained higher implantation rate and clinical pregnancy rate than patients with natural or semi-HR cycles (29.3% vs. 21.5% vs. 25.6%, P=0.01, and 48.7% vs. 42.7% vs. 36.1%, P=0.01, respectively). This finding was not changed in patients with thin endometrium (≤8 mm). A Subanalysis in patients with HRT showed that the implantation and clinical pregnancy rate was higher in patients without ovulation than ovulatory patients (29.8% vs. 16.9%, P<0.01, and 49.5% vs. 26.3%, P<0.01, respectively). This study suggests that HRT increases the possibility of pregnancy. Further, our data showed that ovulation in HRT cycle has a detrimental effect on pregnancy. Therefore, we recommend that HRT should be used in FET cycles, and ovulation of patients should be evaluated during the treatment.
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Li
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Xiong
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Ting
authors.initials: T
authors.lastname: Luo
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Xiyuan
authors.initials: X
authors.lastname: Dong
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Huang
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Hanwang
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology Wuhan, People's Republic of China.
authors.forename: Jihui
authors.initials: J
authors.lastname: Ai
keywords: Frozen-thawed embryo transfer; clinical pregnancy rate; hormone replacement treatment; implantation rate; natural cycle