They said very specifically they don't record what you say for advertising. It was specific enough that it almost seems an admission that they use it for something else.

However, there are plausible explanations for your spouse getting ads for things she's spoken with her phone in the room - for example, the patient googled the medication later or wrote about it on facebook, and facebook knows thay your spouse and the patient likely had a conversation based on location data showing that they walked down a hallway together.