Comparison of pregnancy, implantation, and multiple gestation rates for day 3 versus day 5 embryo transfers

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.