To determine whether IVF clinics are compliant with American Society for Reproductive Medicine (ASRM) and Society for Assisted Reproductive Technology (SART) (ASRM/SART) guidelines and assess the multiple pregnancy outcomes according to the number of embryos transferred.Retrospective cohort study.Not applicable.Data from 59,689 fresh first autologous IVF cycles from the 2011–2012 SART registry.None.Percentage of compliant cycles, multiple pregnancy rate (PR).Between 2011 and 2012, a total of 59,689 fresh first autologous cycles were analyzed. Among cleavage-stage ET cycles, the noncompliance rate ranged from 10%–27.4% depending on the age group. The multiple PR was significantly increased in noncompliant cycles involving patients <35 years (38.1% vs. 28.7%) and 35–37 years (35.4% vs. 24.5%) compared with compliant cycles. Among blastocyst-stage ET cycles, the highest rate of noncompliance was seen in patients <35 years old (71%), which resulted in a statistically higher multiple PR (48.3% vs. 2.8%) compared with compliant cycles. Far fewer cycles were noncompliant in patients 35–40 years of age. In a subanalysis of compliant cycles, transferring two blastocyst embryos in patients 35–37 years and 38–40 years resulted in a higher live birth rate compared with the transfer of one embryo (50.4% vs. 40.9% and 42.1% vs. 30.0%, respectively) but the multiple PR was also significantly higher (40.5% vs. 1.7% and 34.0% vs. 2.0%, respectively).Most first fresh autologous IVF cycles performed from 2011–2012 were compliant with ASRM/SART guidelines, except those that involved a blastocyst ET in patients <35 years. Despite compliance, cycles that involved the transfer of >1 embryo resulted in a high multiple PR, whereas noncompliant cycles resulted in an even more remarkable multiple PR for both cleavage and blastocyst-stage embryos. Clinics need to be more compliant with ET limits and ASRM/SART need to consider revising their guidelines to limit the number of blastocyst transfer to one in patients ≤40 years of age undergoing their first IVF cycle. Furthermore, decreasing the number of cleavage-stage embryos transferred in patients ≤40 years of age should also be considered.