
I think this is quite arguable on a person to person basis.
I just had my first baby and I noticed two things with my memory:
1. I forgot a lot of smaller things - I.e. My car keys, locking the front door etc.
2. I was better at remembering lists of things and multitasking.
However I've always had a great memory when it comes to phone numbers and work stock codes and the like.
However I think that the changing situation is likely to cause an equal amount of memory problems. A woman is facing a new experience, changing body and a whole new area of life. Who can claim that in a new situation they always remember everything they know or have been taught?