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Published on: March 2, 2017
Ectopic pregnancy rates with frozen compared with fresh blastocyst transfer
1Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, California 94304, USA.
Objective:
To compare the rate of ectopic pregnancy (EP) with fresh versus frozen blastocyst transfer in our program during the same time period.
Design:
Retrospective analysis.
Setting:
University IVF program.
Patient(S):
Women who achieved a clinical pregnancy after IVF between 1998 and 2005.
Intervention(S):
In our program, cryopreservation is performed at the blastocyst stage. Embryo transfer was performed 1 to 1.5 cm short of the fundus by abdominal ultrasound guidance.
Main Outcome Measure(S):
The incidence of EP was examined in relation to fresh versus frozen blastocyst transfer.
Result(S):
In the frozen blastocyst group, there were 5 EPs out of 180 clinical pregnancies (2.8%), and there were 10 EPs out of 564 clinical pregnancies (1.8%) in the fresh blastocyst group.
Conclusion(S):
The rate of EP is not significantly increased after the transfer of frozen thawed blastocysts compared with fresh blastocyst transfer.
