Stopping progesterone?

I've been on progesterone supplements since the day after I was inseminated (<a href="https://glowing.com/glow-fertility-program">iui</a>) I'm now 11+5 and they're wanting me to stop my progesterone. I've already had a subchorionic hematoma so I'm really nervous to stop. Can't it makes me lose my baby? I'd rather take progesterone throughout the pregnancy than risk my baby.