How old is too old to adopt a newborn

My first born I was 20 and as you know I was turning 39 when we adopted our dd. I had a rough physical year and had it not been for that YOU BET I WOULD DO IT AGAIN. I feel better now, but since I had made peace with being through, I am still at peace, but obviously you are not at peace. Take the plunge and go for it. Your next baby will be close to you 2 year old and age. Whats' another few year's. I do think 40 is too old for some people, but I think 30 is too old for some people. But not people that LOVE big families.