Question: what episode does meredith tell derek she's pregnant in season 9?
Answer: Season 9, Episode 7: Meredith Tells Derek That Zola's Going to Be a Big Sister. Derek might be dreamy and all, but if we're being honest, Meredith's usually the one who goes for the romantic gestures. After finding out that she's pregnant, Mer buys Zola a "World's Best Big Sister" shirt.