The prognosis for live birth among untreated infertile couples

To estimate the likelihood of live birth and the impact of prognostic factors among untreated infertile couples. Cohort follow-up study. Eleven infertility clinics in academic medical centers. Two thousand one hundred ninety-eight couples with infertility of >1 year in duration. Untreated months of observations on 873 untreated couples (18,364 months) were combined with observations before the first treatment among 1,325 treated couples (9,761 months). Diagnostic tests as indicated. Time to conception for live birth; effect of baseline characteristics estimated by means of proportional hazards analysis. There were 263 live birth conceptions during 28,125 months of untreated observations. The cumulative rate of conceptions leading to live birth was 14.3% at 12 months. The relevant prognostic factors were pregnancy history, duration of infertility, female partner’s age, male defect, endometriosis, and tubal disease. A prediction score based on these factors would be accurate in approximately 62% of cases. The estimation of live birth among untreated infertile couples is sufficiently accurate to be useful in the clinical management of infertility and in the planning of clinical trials.