This episode makes absolutely no sense. So what happens when Karla Four's "father" reaches the point of birth - does he crawl back into her womb?!? The accelerated de-aging also makes no sense: people don't get older faster when they travel at high warp speeds in the "real" universe - why do they get so much younger in the reverse-universe? And why do only the people and their uniforms de-age, but not anything else like the Enterprise itself. These problems are sorta explained in Allan Dean Foster's novelization but even he has Spock and others comment on the silliness of these issues. Author Fred Bronson claimed this was due to Einstein relativity, but that clearly doesn't apply at warp speed. In "normal" space the crew doesn't age as rapidly as they deage when travelling at warp.