Pablo makes great points about the suffering of loved ones, etc. But, modulo those points, I'd say making a life is as important as saving a life. (I'm only going to address the potentially contentious "rephrase" here, and not the original problem; I find the making life / saving life case more interesting.) And I'm not a utilitarian.

When you have a child, even if you follow the best available practices, there is a non-trivial chance that the child will have a worse-than-nothing existence. They could be born with some terminal, painful, and incurable illness. What justifies taking that risk? Suggested answer: the high probability that a child will be born to a good life. Note that in many cases, the child who would have an awful life is a different child (coming from a different egg and/or sperm - a genetically defective one) than the one who would have a good life.