Back muscle spasms?

Sara

I am 23 weeks and lately I have been having back muscle spasms randomly. Nothing I'm doing is bringing them on, I could be standing, sitting or laying down. The pain lasts about a minute or two but it completely takes my breath away and I can't move at all. Is anyone else experiencing this? Is this normal?

On a side note, I've never had any prior back injuries and this is my 3rd baby. I've never experienced this before with my other 2.