Comparison of Transfers of Fresh and Thawed Embryos in Normal Responder Patients
|Infertility||Procedure: Embryo cryopreservation Procedure: Fresh blastocyst transfer|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
|Official Title:||Comparison of Transfers of Fresh and Thawed Embryos in Normal Responder Patients|
- Clinical pregnancy (fetal heartbeat observed on ultrasound at 7 weeks gestation) [ Time Frame: 7 weeks gestation ]
- Ongoing pregnancy at 10 weeks gestation [ Time Frame: 10 weeks gestation ]
- Implantation rate (ratio of the number of fetal heart tones to the number of transferred blastocysts) [ Time Frame: 7 weeks gestation ]
|Study Start Date:||October 2007|
|Study Completion Date:||October 2010|
|Primary Completion Date:||October 2010 (Final data collection date for primary outcome measure)|
Experimental: Blastocyst transfer in PTEC cycle
Transfer of two blastocysts derived from thawed bipronuclear oocytes that were subject to post-thaw extended culture (PTEC).
Procedure: Embryo cryopreservation
Cohort cryopreserved as bipronuclear (2pn) oocytes, then thawed and cultured to the blastocyst stage before transfer to the uterus.
Active Comparator: Fresh blastocyst transfer.
Transfer of two fresh autologous blastocysts following controlled ovarian stimulation.
Procedure: Fresh blastocyst transfer
Fresh blastocyst transfer following cycle of controlled ovarian stimulation.
The purpose of this study is to determine if blastocyst transfers in cycles of post-thaw extended culture (PTEC) have different efficacy than transfers of fresh blastocysts in patients with expected normal response to ovarian stimulation.
Multiple studies have found altered endometrial histology and gene expression following controlled ovarian stimulation.
PTEC cycles require cryopreservation of the entire 2pn oocyte cohort in the prior cycle. Once thawed, the embryos are cultured to the blastocyst stage before transfer.
In typical cycles using frozen-thawed embryos, many thawed embryos that appear to survive do not actually resume and continue development. PTEC ensures the transfer of embryos that resumed development and continued developing at least to the blastocyst stage (4-5 days post-thaw).
The viability of a blastocyst in a PTEC cycle has been shown to be on par with that of a fresh blastocyst. Therefore, comparing outcomes of blastocyst transfers in PTEC cycles with that in fresh autologous cycles allows the potential endometrial impact of controlled ovarian stimulation to be assessed.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00963625
|United States, Nevada|
|Fertility Center of Las Vegas|
|Las Vegas, Nevada, United States, 89117|
|Principal Investigator:||Bruce Shapiro, M.D., Ph.D.||Fertility Center of Las Vegas|