Is it bad if I have sex with someone while pregnant with my ex?

A few people have told me do what you want it's not like your hurting the baby. My ex has basically told me before that if I ever did that it makes me a hoe. I'd understand if I was going around sleeping with lots of people while pregnant, then I'd be a hoe, but I'd never do that. I'm talking about one person who I like. Am I a hoe if I did do it?