I've also been dealing w this. I am now 32 weeks pregnant w my fourth child, first girl, and I've read about the round ligament deal but everything I've found says the pain should not be severe and only last a short amount of time and this pain happens maybe once or twice a week but not caused by me straining myself or a sudden jerk. It lasts up to an hour or sometimes over and it's very painful almost like a contraction strong feeling but I know that's not it either.
I had the same pain a belly belt or getting a back massage or a pelvic massage helped me also a exercise ball works wondera
I have the exact same thing. Happened about 25 week also. Now 34wks, still the same. Dr said make sure you drink alot of water. She said it had to do with your round ligaments. I'm carrying very low.