How old is too old to adopt a newborn

I was 40 and 42 when we adopted our two - now they are 4 and 2, and I am 44. DH is 41. If I was 3-4 years younger I would definitely adopt a third! I definitely think about "how old I will be when..." and I worry they may get teased about their oldddd parents when they are teens, but I know we are giving these boys the best life we can. Yes, I get really tired sometimes...yes, I am probably the oldest mom at preschool...yes, most of our local friends have kids at least 10 years older than ours...but I am also amazed at how many of my high school and college friends also have toddlers right now, so I am definitely not unique. I think I am more patient and more "satisfied" with my life than I would have been if we adopted younger...i.e. I don't regret not doing things, because I had time to do many things (travel, etc.) before kids. I can honestly say I'm not sure if I'd adopt a newborn at that age (40) if I already had 5 kids, but you know what you can handle, what's in your heart and what's best for you and your family, so I say go for it! You can always plan and save and get ready in the meantime, and then revisit your decision later to make sure it's what you both still want. Cate