title: Primary sterility of unknown causes--some possible immunological causes.
authors.forename: S A
authors.initials: SA
authors.lastname: Birkeland
authors.forename: K
authors.initials: K
authors.lastname: Kristoffersen
mesh_terms: D000367:Age Factors; D019411:Clinical Laboratory Techniques; D003933:Diagnosis; D007246:Infertility; D012098:Reproduction
keywords: Age Factors; Examinations And Diagnoses; Infertility--etiology; Infertility--men; Infertility--women; Laboratory Examinations And Diagnoses; Laboratory Procedures; Reproduction