Get a rib belt and cinch it up!!! It helps. I have two broken ribs ....one from each boy. Now with a girl on the way they have spread again and are KILLING ME!!!. at night a travel pillow under my ribs helps too.
Yes. It's because your uterus is growing upwards into your rib cage. Last pregnancy my ribcage expanded almost 2 inches in diameter! So painful. But once baby drops it feels a bit better. If this is your first baby that should be around 36 weeks. It may hurt more on the right side because your liver is also there taking up even more space. Massage helps a bit, sleeping on the side that hurts most helps. Tylenol, warm shower or bath, and trying to eat smaller meals all help. Good luck!