We analyzed the importance of five factors (the nature and extent of adhesions, the macroscopic aspect of the endosalpinx, the thickness of the tubal wall, and the diameter of the hydrosalpinx) for the prediction of subsequent conception in 108 patients treated for hydrosalpinx. Each factor was classified into a score immediately after operation. After follow-up study, each factor was correlated with the pregnancy outcome. The prognostic information of the four most promising factors was combined with Bayes' discriminant analysis. The results clearly indicate the presence of three prognostic classes: a good one (n = 27); an intermediate one (n = 44); and a poor one (n = 37) with a probability of intrauterine pregnancy of 77%, 21%, and 3%, respectively. Moreover, the results allow for a simple classification of each future patient into the appropriate prognostic group. In the present era of in vitro fertilization, this differentiation may have consequences for an optimal treatment of patients.