Sometime in the weeks leading up to your delivery, the nurses at your hospital/clinic will give you a list of items that you should bring with you when you are admitted.
Most hospitals in Japan require first-time mums to stay up to 5-6 days and 2nd/3rd time mums to stay up to 4-5 days (up to 10 days for cesarean deliveries), so think about things you might need for that many days away from home.
Let`s have a look and see what everything is, and where to get it.
* some hospitals will require more or less, so please check your list carefully too.
母子手帳 - boshi techo - mother and baby book
(you should already have these and be bringing them to check-ups)
The following things can be packed in a small suitcase or carry bag and should be named and be easy to find (by you or your partner) at the hospital...
パジャマ - pajama - night wear that is easily accessible with buttons down the front
For labor, small snacks, energy jelly like this and a pet-bottle cap with a straw attached (available at all 100yen shops) are recommended. Depending on the season you may want to bring a fan (summer) or hand warmers (winter) as well as something for your partner to use to massage your lower back (tennis balls are recommended).
For the hospital stay, small change for vending machines, a waterproof bag for dirty clothes, small plastic bags, your phone and phone charger, a camera, headphones, a book to read, a notebook/diary and pen are also recommended.
* Most hospitals will ask you to bring one outfit for the baby to wear home when you are discharged (you will need clothes for yourself too). Something easy to put on/take off for both of you is best.
I got most of these things from baby shops like Akachan honpo or Nishimatsuya. Other things I had at home or I bought online from Amazon japan.
I will put links to the products I bought from Amazon japan if you need them...
Nivea lip cream (花王 ニベア ディープモイスチャーリップ 無香料) here
Dacco wet cotton wipes (クリーンコットンナチュリーゼベビー 30包入) here
Moony post-partum pads (ムーニー いちばんやさしい お産用ケアパッド Lサイズ5枚) here
... and some other handy new mother`s items ...
Moony breast-feeding pads (ムーニー お肌にやさしい 母乳パッド 68枚入) here
Pigeon breast-feeding supplements (ピジョン 母乳パワープラス 錠剤 90粒) here