Let me give a shout-out to two of the most renowned newborn photographers: Anne Geddes and Ana Brandt. `I know how difficult it is to hone your skill, especially when you want to stand out from the crowd. I spent 8 years working almost solely with babies to capture those lovely poised and peaceful newborn images.
So ideally, those first two weeks are the prime time for a posed newborn photography session. However, newborn sessions can absolutely be held at or after two weeks.