Health insurance plans are evaluated here in terms of ability to guarantee financial access to a set of basic fertility-related health services. Extent of coverage is determined by whether a service is a contract benefit, its market cost, and how often it is used in a given population in one year. Comprehensive coverage removes a deterrent to utilization of preventive care such as wellbaby visits, prenatal care, and family planning. In a total population of women of child-bearing age, each is likely to need some fertility-related care in a given year. The method of calculating adequacy involves using best available estimates of deliveries, abortions, etc. per 1,000 women, and, within each category, of components such as cesarean section. Local or national cost data can be used to derive an average cost per service and an aggregate for a group. The method of comparing this with plan benefits depends on the way benefits arc expressed. Jacksonville, Fla. medical market data were used in a trial of the method on a plan for Federal employees, which shows 70 per cent coverage of estimated expense.