I read in japan pregnant women continue to eat sushi and raw fish when pregant. i read that there are no conclusive studies regarding the ban, true?

Absolutely: It is very common in hawaii as well! all sushi served in america by law must be flash frozen and rethawed before it is served, killing fish parasites. So that's not a worry (and most doctors do not know this) the concern is mercury, which is actually pretty high in the types of fish in sushi. But... The amount of fish is so small its not a great worry. Acog says no, i say enjoy in moderation.

The FDA disapproves!: Sushi should be avoided during pregnancy for two reasons. (1) risk of bacterial infection complicating the pregnancy. (2) risk of exposure to mercury complicating the pregnancy. Certainly not worth the risk during pregnancy. Cooked sushi or vegetable-only sushi should be fine, but then we'd worry about the person making the sushi having washed his hands after handling raw fish.