Popular actor and comedian Tina Fey's decision to have a child at 41 was a very clear and conscious decision, which her and husband Jeff Richmond arrived at together after careful consideration. They worked together on the show '30 Rock', on which Richmond served as a composer, and were conscious that they might find themselves regretting not doing so years later if they just focused on the show and waited for it to come to a natural end. And so, they didn't!
Fey and Richmond had already had one child but welcomed a second; her daughter Penelope; who was conceived when she was 41. They had previously said that they were worried that they might find, later in life, that 'part of their family was missing' if they didn't act when they did, so we're happy for them.