Would I be wrong ?

So me and my boyfriend recently broke up after 2 years together and I'm pregnant... We had been trying for a baby for a year before it finally happened for us and then 3 months into my pregnancy (I am now 6 months) things started going down hill. He has moved on & already has a new gf. I myself have been talking to this guy for a while now & we started out as good friends but since my break up he's really stepped up & has been beyond supportive. We've decided to start dating & I was just curious as to if it would be looked down upon if I were to be intimate further into our relationship while pregnant with another mans baby ? I feel it's wrong but I need someone else's opinion.