Second try: who returns for additional assisted reproductive technology treatment and the effect of a prior assisted reproductive technology birth.

ObjectiveTo evaluate the effect of a prior assisted reproductive technology (ART) live birth on subsequent live-birth rates.DesignHistorical cohort study.SettingClinic-based data.Patient(s)The study population included 297,635 women with 549,278 cycles from 2004 to 2010 from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System. Try 1 refers to ART cycles up to and including the first live birth, try 2 to ART cycles after a first live birth.Intervention(s)None.Main outcome measure(s)Live-birth rates by cycle number, try number, and oocyte source.Result(s)Younger women at try 1 are more likely to return for try 2. Women returning for try 2 were more likely to have had an ART singleton versus multiple birth (33.2% after a try 1 singleton versus 8.1% after twins and 4.9% after triplets) and were less likely to have a diagnosis of diminished ovarian reserve or tubal factors. Live-birth rates were significantly higher for try 2 compared with try 1 for autologous fresh cycles, averaging 7.7 percentage points higher over five cycles. Live-birth rates were not significantly different for try 2 versus try 1 with thawed autologous cycles or either fresh or thawed donor cycles.Conclusion(s)These results indicate that when fresh autologous oocytes can be used, live-birth rates per cycle are significantly greater after a prior history of an ART live birth.