Elective single blastocyst transfer reduces twin rates without compromising pregnancy rates.
OBJECTIVE
To compare IVF outcome in single versus two blastocyst transfer in good-prognosis patients.


METHODS
Retrospective data analysis.


METHODS
University-based IVF practice.


METHODS
Assisted reproductive technology outcome was compared in 41 patients who underwent elective single blastocyst transfer and 66 patients who underwent two blastocyst transfer.


METHODS
None.


METHODS
Implantation rates, clinical pregnancy rates, cumulative pregnancy rates, twin pregnancy rates.


RESULTS
Blastocyst cycles between January 2003 and August 2004 (n = 238) were reviewed. Criteria for elective single embryo transfer established by our clinic were applied retrospectively to blastocyst cycles. Patients who met the criteria were divided into two groups, those who underwent elective single embryo transfer (eSET) and those who underwent two embryo transfer (2ET). Patient and cycle characteristics were similar for both groups. There were no differences in implantation rate (76% vs. 66%) or pregnancy rate (76% vs. 79%) between the eSET and 2ET groups. There was a significant difference in the number of twin pregnancies (3.2% vs. 62%) in the eSET versus 2ET group. Cumulative pregnancy rates were found to be 83% for both groups.


CONCLUSIONS
Single blastocyst transfer can be performed in good-prognosis patients without compromising pregnancy rates. Twin pregnancy rates can be significantly reduced with eSET.
Criniti
Amy
A
University of Washington Fertility and Endocrine Center, Seattle, Washington, USA. arcrinit@yahoo.com
Thyer
Angela
A
Chow
Gregory
G
Lin
Paul
P
Klein
Nancy
N
Soules
Michael
M
D000328:Adult; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D006801:Humans; D010062:Ovulation Induction / Q000379:methods; D011247:Pregnancy; D018873:Pregnancy Rate; D011272:Pregnancy, Multiple / Q000706:statistics & numerical data*; D011379:Prognosis; D012189:Retrospective Studies; D014427:Twins