All I can say is Never Assume that Pizzas are OK unless you have tested at least hourly for the next 12 hours.
I reply to this old thread because you are correct.
Yesterday evening we made at home a pizza "al tegamino" (because havin only a gas oven, you can only make this way) so it had a bog spongy crust, and was made with self raising flour.
BG after two hours was low 4.6 and made me suspicious. At midnight i felt a bit dizzy and decided to re test. 9.6
This morning the fasting BG was still high. 6.2.
Other ingredients were good and fresh and wew only olive oil, basil, tomato sauce and salt, I think the problem was in flour and preparation.
I suspect the kind of topping and the base make a dofference on the effect of pizza so I think it is better to don't eat a lot of it even if home made.