I think this was a wake-up call. You can call the pregnancy a miracle, if on some level you truly wanted to get pregnant. Otherwise, it's an accident. Maybe he's an awful person, and maybe he's not. It sounds to me like he's just desperate for you not to have a baby with his DNA, so he'll say and do anything. It's not cool, but it's what desperate looks like. Take that into account as you make your decision; be sure not to act out of pure selfishness. Here's a thought: Maybe he is a good guy who would feel guilty not caring for a child with his DNA, even though he is deathly against it. Could that be part of his desperation? You owe it to him and to your fetus/future baby and even to yourself to consider his feelings, too.
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You need to decide right now if you are prepared to do this without any input from him. That means none of his money, energy, time.... If the answer is yes, then carry on with the pregnancy, but do NOT try to stick him with child support. If the answer is no, then have a real heart to heart with him and maybe a therapist who can get to the root of his concern and help determine if this is likely just cold feet or a long-term perspective. NEVER go into a life-long commitment waiting for somebody to "come around". That is disaster in the making, and you will have nobody but yourself to blame for that disappointment.
Also, please don't minimize what you have heard him say with his own mouth. If he tells you that he does not want to care for a baby, please hear that, and don't blow it off. Assume that he means what he says. Don't shove a baby down his throat and then wonder why he hates for the rest of his life. He is not a bad guy just because he asked you to terminate the pregnancy. He didn't slam you against a wall when he said it, did he? Is he not entitled to tell you how he feels about this and express his desires?
Were you ever actively trying to get pregnant? If not, then that "likelihood" that the doctors mentioned should be less of an issue. If this is not the right time or place, then it's just not. Talk to another doctor; conception is promised to no one, no matter the health. Don't let the irresponsibility between you make this decision for you. ("I'll just step out into the street with my eyes closed. If I get hit, then that's a sign from God....") Maybe your pregnancy is a miracle. It could also be a random occurrence. It happens all the time. If you think that this is your one bite at the apple, then have a baby, but know that one set of consequences of that decision will be NO SUPPORT from the man who sat with you and honestly told you that he does NOT want to shoulder the responsibility of parenthood. No right or wrong here. Just wrong for one of you to FORCE your decision on the other.
Good luck.
ETA: Sorry, lady, child support falls on the people who want to be parents. Any woman who chooses unilaterally to have a baby should shoulder the responsibility on her own. If tax-payers get stuck with the bill, it's not the fault of the person who opted not to have a baby. that person had a valid solution. Period. I'm thinking that if this were the other way around and she did not want to have a baby but he did, you would again tell her that it's totally her call. No wonder certain men feel so disenfranchised when it comes to parenthood. They only have 50% rights and responsibility when they are in complete agreement with the women. Otherwise, they have 0% rights and 100% responsibility. I don't see why every one of them wouldn't choose to run from that. If women took more responsibility for their own reproductive decisions, fewer pregnant women would get pushed down the stairs. Not to bash the poster because I don't know her, but maybe the volatile fights are initiated by her and he knows that he does not want to coparent with a loon. Maybe she's just good in the sack and nowhere else. You don't know what his reasons are, but they are just as valid as hers.
"If you want people to be responsible for their children, you have to give them the right to decide whether or not they have children."