I WAS RIGHT! 

Suzie Plakson was cast as K'Ehleyr because the production staff were impressed with her performance as Doctor Selar in “The Schizoid Man”. Tracy Tormé, who had written “The Schizoid Man”, had wanted to develop a romance between Selar and Worf, but the idea was overruled when “The Emissary” was being planned. Tormé complained that the premise was “obvious. Had it been a Vulcan, it would have been a lot more interesting.” (Captains’ Logs: The Unauthorized Complete Trek Voyages)

(Via Memory Alpha)