If you desire pictures of your baby in curly poses it is best to take newborn photos within the first two weeks of life. During this time babies tend to go into curly poses much easier than older babies and don't mind having their clothes off if they are kept warm.
At this age, they are more likely to curl up in “womb-like” poses, stay asleep longer, don’t mind being unclothed, and usually have their feeding schedules set to at least every two hours.
I usually schedule these shoots one week after the due date but can make adjustments once the baby is born.
If you miss the two week window it's no problem, great photos are still possible! The benefit of waiting longer than two weeks is the possibility of a larger range of photos. Babies at this stage are awake longer and more interested in their surroundings so pictures where baby is still cute and sleeping as well as pictures of baby awake to see their beautiful eyes are possible.