No. The key part of SF is the "What if...?" question. A Science Fiction story should posit a difference about the setting from our own world and this difference should have consequences. Alternate history stories like "The Man in the High Castle" are Science Fiction. "What if the Nazis won?".

Likewise the key part of Romance genre fiction is the Happy Ending. It doesn't matter whether they sleep together (a lot of Romance aimed at older and Christian readers doesn't have any sex at all), or get married, but there must be a Happy Ending.