I had my children in my 40's and I felt "old" then. But more women over 50 are having babies. It's usually a carefully thought-out choice, by women who are financially stable and physically fit. Remember, the average life expectancy for women is now 81 and our quality of life is greatly enhanced by modern medicine, nutrition and fitness programs. You might wish to read this story about an executive for a well-known corporation who had her baby at 52: http://achildafter40.com/new-mom-at-fifty-two/.
Each story of "delayed" motherhood is unique (whether giving birth or adopting over 50)and should be perceived on its own merit. We should get ready for this growing maternal trend.