Objective: Trying to diagnose clinically some suggested causes of unexplained infertility related to ovum picking, fertilization, embryo growth and implantation and to outline the most suitable management needed for these cases. Design: Prospective controlled diagnostic and management study. Setting: 50 fertile cases as control. Patients: Assessment of ovum picking was determined clinically in 50 cases of unexplained infertility, in addition to certain causes related to fertilization, embryo growth and implantation in another 50 cases having failed IVF used for management of similar cases. Interventions and main outcome measure: Accessibility of the ovulation site to fimbrial end of the tube and in turn ovum picking was clinically determined by the use of combined selective salpingography and ovarian sonography. Other causes were determined by determining the cause of failure of IVF used for managing similar cases of unexplained infertility. Results: Successful clinical diagnosis of ovarian picking could be significantly obtained in 90% of the fertile cases compared to 52% of the infertile cases (P<0.005). Meanwhile, failed ovum picking could be diagnosed in 42% of the infertile cases compared to only 2% of the fertile cases (P<0.005). Other causes were also diagnosed and they included failure of formation of an embryo recorded in 14 (28%) of cases, failure of implantation in 18 (36%) and failure of growth and development of the fertilized ovum or the implanted embryo in 9 (18%) cases. Significant management could be recorded in 69.6% of cases managed as failed ovum picking compared to 29.6% in the rest of cases managed as unexplained infertility (P<0.005). In the same way the other causes were significantly managed and cured by managing the related cause and not empirically as unexplained infertility. Conclusions: Failed ovum picking by the tube, failure of formation of an embryo, failure of implantation and failure of embryo growth could be identified clinically as causes of unexplained infertility. Successful management was encountered more in the cases specifically treated for the identified cause and not generally as cases of unexplained infertility.