This study is designed to determine the cost-effectiveness of a fast track to in vitro fertilization (IVF) infertility therapy by conducting a randomized prospective clinical trial to compare its success rates and costs to that of conventional therapy. Eligible couples with a female partner aged 25-39 years and a male partner without severe male factor infertility will be randomized to either a conventional treatment or a fast track to IVF arm. Infertility is a major health problem in the United States. Primary or secondary infertility affects 10-15 percent of American couples and costs billions of dollars annually in medical costs and lost productivity. Projections show that 5-6.3 million women will be infertile in the year 2000, and 5.4-7.7 million women will be infertile in 2025. In recent years, infertility diagnostic evaluations have been streamlined because of the increased success of treatment strategies. Unlike many other areas of medicine in which treatment is based on the specific clinical diagnosis, new standardized infertility treatments are now used for nearly all causes of infertility. Conventional treatments for infertility have extremely variable protocols, success rates, patient access, and costs to both patients and insurance carriers. For most infertility treatments, success rates are lower than natural rates in fertile couples, and for some therapies, particularly gonadotropin- induced ovulation, the frequency of multiple births is unacceptably high. In contrast, success rates for the most technologically advanced methods, particularly IVF, have not only surpassed those of gonadotropin-based conventional treatments, but are now higher than natural fertility rates. IVF and related strategies have been modified successfully to reduce adverse events, particularly multiple births. Costs and insurance coverage have a direct effect on access to infertility services and the choice of treatment. Massachusetts is one of only five states that require insurance carriers to provide comprehensive coverage for infertility treatment, including IVF. Even in these states, affected couples are usually required to have failed conventional infertility therapy before coverage for IVF is authorized, despite the higher rate of adverse events and lower pregnancy rates of conventional treatments. The proposed study takes advantage of two local features: (1) The BIDMC/Boston IVF/HVMA is the largest infertility treatment center in the United States, treating over 2,300 new patient couples each year. During the study's two-year enrollment period, approximately 1,200 eligible couples per year will be available for recruitment, and 800 will be enrolled. (2) Because insurance coverage for infertility is required by Massachusetts law for all participants, the choice of therapeutic alternatives is not affected by the patients' ability to pay for treatment.