A two- versus three-embryo transfer: the oocyte donation model.
OBJECTIVE
To compare implantation and pregnancy rates in oocyte recipients undergoing a two-embryo versus three-embryo transfer, 3 days after retrieval.


METHODS
Retrospective comparative analysis.


METHODS
University-based in vitro fertilization center.


METHODS
All oocyte recipients undergoing embryo transfer from January 1, 1997 through August 31, 1999.


METHODS
Recipients received two or three embryos.


METHODS
Implantation, and clinical and multiple pregnancy rates.


RESULTS
Seventy-three recipients underwent a two-embryo transfer, and 376 had three embryos replaced. The numbers of oocytes retrieved (12.7 +/- 0.89 vs. 13.1 +/- 0.36) and embryos obtained (8.05 +/- 0.65 vs. 8.77 +/- 0.27) did not differ between the two-embryo and three-embryo transfer groups, nor did the proportion of patients with embryo cryopreservation (54.3% vs. 42.6%, respectively). There was no significant difference in pregnancy or implantation rates when comparing those patients with a two-embryo transfer to those with a three-embryo transfer. Significantly, 13.8% of the pregnancies in the three-embryo transfer group were triplet.


CONCLUSIONS
Reducing the number of embryos transferred in an oocyte donation cycle can lower the incidence of triplet pregnancies without significantly lowering the overall pregnancy rate.
Licciardi
F
F
Department of Obstetrics and Gynecology, The Program for In Vitro Fertilization, Reproductive Surgery and Infertility, New York University School of Medicine, New York, NY 10016, USA. fredivf@yahoo.com
Berkeley
A S
AS
Krey
L
L
Grifo
J
J
Noyes
N
N
D015925:Cryopreservation; D010064:Embryo Implantation; D004624:Embryo Transfer / Q000379:methods*; D004622:Embryo, Mammalian / Q000502:physiology; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D018587:Oocyte Donation; D011247:Pregnancy; D011256:Pregnancy Outcome; D011272:Pregnancy, Multiple; D011374:Progesterone / Q000008:administration & dosage; D012189:Retrospective Studies
D011374:Progesterone