Congratulations!
It will be so exciting reading about this new development.
Not sure if you are familiar with the Bradley Method (an alternative to LaMaze)?
I'm not pushing the method, I just know that the recommended diet's foundation is a lot like IP P4 (well, with lots of dairy and bread) in its emphasis on getting 100g of protein a day.
Thought you might enjoy the link:
http://www.bradleybirth.com/Diet.aspx