discordant couple
n.— «The physician who performed the inseminations reported that in January 1990 a second HIV-1-discordant couple (i.e., seropositive husband with hemophilia, sero negative wife) underwent one insemination using the same density gradient centrifugation procedure. Nine weeks after the insemination, the woman was negative for HIV-1 antibody by EIA and Western blot and for proviral HIV-1 DNA by polymerase chain reaction.» —“Morbidity and Mortality Weekly Report” USA Today/Gannett Nat. Info. Network Apr. 22, 1990. (source: Double-Tongued Dictionary)