Here's a question: why would two people who are supposedly in love say things to hurt each other?
Whatever it was that he said, I would imagine that it was one of those things that the rest of us would see as a deal breaker. Whatever he said was certainly abhorrent enough to have him banned from contacting the family.
It's your parents job to guide you into making good decisions for yourself. If you are proving yourself unable to make good decisions, they may have to step in. The whole reason you went to your parents in the first place would have been because you trust their judgement and needed some wisdom, yes?
Your boyfriend calls you childish for taking this to your parents. This just proves the point that your parents are seeing. He's not taking responsibility for hurting you in the first place - instead, he's blaming you for seeking advice from a trusted source.
The only way I can see this as being recoverable is for your boyfriend to speak with your family and explain himself. IF he does a good enough job of owning his own behaviour and working on change, they may come around. It goes without saying that you also need to grow up and stop hurting him too. Emotionally mature, reasonable people just don't hurt each other like this.
Lastly, if the two of you were to get pregnant just to stay together, it would only prove to your parents how immature you both are.
Never regret anything that has happened in your life. It cannot be changed, forgotten or undone. So, take it as a lesson learned and move on.