What are the pregnant women holding in MIST movies?

[Electromog]

There are a lot of movies in the MIST series about soaplands where you can get the girls pregnant.

Near the end of the movie there's usually a scene where they reveal they're pregnant and they tend to be holding something. You can't really see what exactly because it is always blurred out. It looks like some kind of book.

For example MIST-499:


And MIST-495:


I'm assuming it's something Japanese people would have no trouble recognising even when blurred, but as some European dude I have no clue.

Can somebody explain what the item is supposed to be?

 

[tarmyg]

Maternal and Child Health Handbook? From https://thewagamamadiaries.com/pregnant-in-japan/

"After confirming your pregnancy, it’s time to go to city hall to register your pregnancy. Only then will you receive your 母子健康手帳 boshi kenkou techou (boshi techou for short, Maternal and Child Health Handbook). This book will be used throughout your entire pregnancy until your child enters elementary school."

This is Japan's official government-issued booklet given to every pregnant woman. The handbook symbolizes official confirmation of pregnancy.

 

[Electromog]

That does fit with how they use it to "prove" they are preganant, so that's probably it.

Thanks, I had never heard of this book.