RESUMEN
PURPOSE: To compare pregnancy, implantation, and multiple gestation rates resulting from day 3 and day 5 embryo transfers after in vitro fertilization emphasizing a subset of patients who met criteria for day 5 transfer but elected to undergo day 3 transfer. METHOD: A retrospective analysis of day 3 and day 5 embryo transfers from January 2001 to June 2002 were evaluated in a community teaching hospital setting. A total of 331 patients < or = 40 years old were included. Using Student's t test, chi2 test, and Fisher's exact test, we compared the pregnancy, implantation, and multiple gestation rates. RESULTS: Pregnancy, implantation, and multiple gestation rates were not significantly different between the subgroup who met criteria for day 5 embryo transfer but elected day 3 transfer. There was no significant difference between similar parameters in the overall comparison of day 3 versus day 5 embryo transfers. CONCLUSIONS: Blastocyst transfers have similar multiple gestation rates, pregnancy rates, and implantation rates when compared to day 3 embryo transfers.
Asunto(s)
Transferencia de Embrión , Embrión de Mamíferos/fisiología , Resultado del Embarazo , Embarazo , Femenino , Humanos , Infertilidad Femenina/clasificación , Estudios Retrospectivos , Factores de TiempoRESUMEN
BACKGROUND: Twice-frozen, thawed embryos may have utilization in vitro fertilization (IVF) cycles. CASE: A 37-year-old woman with endometriosis and infertility returned five years after a fresh IVF cycle. Seven cryopreserved embryos (2 pronuclear [pn] and cleaved) were thawed, and five developed to the blastocyst stage. One blastocyst was transferred, and the remaining four were recryopreserved. This transfer did not result in pregnancy. The remaining four blastocysts were thawed, and two were transferred resulting in a live, singleton delivery. CONCLUSION: Pregnancy can result from cryopreserved 2-pn and cleaved embryos cultured to blastocysts, refrozen and then transferred at the blastocyst stage.