To determine the relationship between number of fertility treatment cycles and pregnancy rates.Prospective cohort study.Eight community and academic infertility practices.Four hundred eight (408) couples presenting for an infertility evaluation.Face-to-face and telephone interviews and questionnaires.Incidence of pregnancy. Cox regression analysis compared the efficacy of cycle-based fertility treatments with no cycle-based fertility treatment after multivariable adjustment.Couples using one to two medications-only cycles had a significantly higher pregnancy rate (hazard ratio [HR] 4.7 [95% confidence interval 1.3-16.6]), a benefit that did not persist after three or more cycles (HR 0.6 [0.1-3.2]). Couples using IUI for one (HR 2.9 [1.4-5.8]), two (HR 2.0 [0.9-4.5]), and three cycles (HR 4.5 [1.8-10.9]) were more likely to achieve a pregnancy. No additional benefit was seen for couples using four or more IUI cycles (HR 1.0 [0.4-2.6]). In vitro fertilization was associated with significant benefit for couples using one (HR 2.8 [1.5-5.2]) and two cycles (HR 2.2 [1.2-4.1]). Couples using three or more IVF cycles had a non-statistically significant higher likelihood of pregnancy (HR 1.3 [0.7-2.4]).Cycle-based fertility treatments may offer a point of diminishing returns for infertile couples: two cycles of medications only, three cycles of IUI, and two cycles of IVF.
View details for DOI 10.1016/j.fertnstert.2010.06.043
View details for Web of Science ID 000285411600021
View details for PubMedID 20659733