Have you switched to latex-free condoms? Sometimes they may be hard to find in the regular drug store, but they are available through online drugstore sites. (The lambskin don't protect against STDs, only pregnancy, so don't use those.)

If you still have itching after you switch from the latex, go see you gynecologist.

My advice would also be to not use home-remedies on your vagina unless your doctor says it's okay. The problem is that you don't want to alter the pH. Your vagina is naturally acidic. Baking soda is basic. This is why doctors say not to douche.

Also, yogurt is for eating. Yes, it has beneficial bacteria, but it also has a lot of other stuff in it, too. Just because it's a "home remedy" doesn't mean it's a good idea. Even if it were, over-the-counter medication is more effective and safe.

Go to your doctor and get it checked.