I think you have had some good advice from the previous posters. Can I just add one thing though....The choice is absolutely yours and yours only. However, I think you need to take into consideration that if your fiance is not 100% sure you have to be prepared to take on raising the child by yourself if it comes to that.
Of course we all want things to turn out perfectly but the reality is, if your relationship falters under the stress of raising a child (which it can) it is almost definitely going to be you left holding the baby (literally!)
Not saying it wont work out for you, but having a baby/child is hard. Having one with someone who is not 100% committed to the idea is much, much harder.
All the best in your decision. I really hope it all works out well for you.
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