No sugar! Especially pure sugar, it's the most needed/easiest way for bacteria and yeast to be fed. It'll alter the pH of one's vagina and make it more hospitable for the bad microbes. You even have to watch lubes, especially if your sensitive. Glycerine is used in lots of things, but it is sugar. Some people cannot even use glycerine lubes.
Lubes that don't have glycerol products are best when you're unsure or sensitive down there.