Long-term outcome in couples with unexplained subfertility and an intermediate prognosis initially randomized between expectant management and immediate treatment

BACKGROUND: We recently reported that treatment with intrauterine insemination and controlled ovarian stimulation (IUI-COS) did not increase ongoing pregnancy rates compared with expectant management (EM) in couples with unexplained subfertility and intermediate prognosis of natural conception. Long-term cost-effectiveness of a policy of initial EM is unknown. We investigated whether the recommendation not to treat during the first 6 months is valid, regarding the long-term effectiveness and cumulative costs. METHODS: Couples with unexplained subfertility and intermediate prognosis of natural conception (n = 253, at 26 public clinics, the Netherlands) were randomly allocated to 6 months EM or immediate start with IUI-COS. The couples were then treated according to local protocol, usually IUI-COS followed by IVF. We followed couples until 3 years after randomization and registered pregnancies and resources used. Primary outcome was time to ongoing pregnancy. Secondary outcome was treatment costs. Analysis was by intention-to-treat. Economic evaluation was performed from the perspective of the health care institution. RESULTS: Time to ongoing pregnancy did not differ between groups (log-rank test P = 0.98). Cumulative ongoing pregnancy rates were 72-73% for EM and IUI-COS groups, respectively relative risk 0.99 (95% confidence interval (CI) 0.85-1.1)]. Estimated mean costs per couple were (sic)3424 (95% CI (sic)880-(sic)5968) in the EM group and (sic)6040 (95% CI (sic)4055-(sic)8125) in the IUI-COS group resulting in an estimated saving of (sic)2616 per couple (95% CI (sic)385-(sic)4847) in favour of EM. CONCLUSIONS: In couples with unexplained subfertility and an intermediate prognosis of natural conception, initial EM for 6 months results in a considerable cost-saving with no delay in achieving pregnancy or jeopardizing the chance of pregnancy. Further comparisons between aggressive and milder forms of ovarian stimulation should be performe