Congrats to you and your wife!
I didn't eat anything special, just balanced diet like meat, veg, fruits. Most important is to continue with folic acid.
I take a glass of low fat high cal milk everyday. No herbal soup or anything. Avoid vit A found in meat organs. Reduce caffeine intake found in chocolates, tea, coffee, soft drinks.
I guess when you reach 2nd trimester, your gynae will prescrible multivits, fish oil.