"Better to have loved and lost" comes to mind. Fearing loss is natural, but I think we have to overcome that and embrace love.
When my son (Brett, 2.5) was conceived my wife and I had been together 10 years and she wasn't supposedly able to have children. Doctors didn't know how it happened, or if it would be successful (my wife @MediKatie has a complicated medical history). It's hard to admit now, but at the time, we did consider abortion because he wasn't supposed to be healthy and was likely to endanger Katie's life. The decision was agonizing, made more so by the fact that our families had recently abandoned us (over our activism and cannabis use). We had nobody to talk to about it and had to decide in secret, alone. There were so many factors to consider and we did a lot of research and soul searching. Finally, one day I was overly emotional about it, and suddenly decided what to do. It came down to, do you believe in life, or not? Maybe that sounds silly now, and I'm not usually someone who acts on feelings, but that really spoke to me. Yes, I believe in life. We either grow or we die. It was time to grow (again), and grow I have! Brett is healthy and happy, and he now has a little sister. Katie and I are pretty swamped with it, but we don't regret that decision at all. Even with the risk that anything could happen. We are just enjoying the love and being aware that loss is a constant in life.
Loss really does leave a scar, it's true, but we CAN love again, even with a broken heart. We have to try to not let fear of loss paralyze us from one of the most magical parts of life, love.