Toddlers abusing me

Stephanie • Mom of 4 kiddos, 1 boy & 3 girls (a set of twins in there) with #5 due in June 2016.
So I'm just shy of 14 weeks. I have a 3 y/o daughter and 2 y/o twin daughters and recently they have been extremely playful with me. They have really been beating up on me. Elbows to the ribs and stomach, jumping on my stomach & legs, and bashing me in the face with whatever they can find. I'm sure they are just trying to play and want my attention. I'm trying to be gentle with them and teach them not to do these things but I'm getting so frustrated. My face hurts from a toy attack to my lower lip.  Ugh.