Is it safe for pregnant women to drink milk tea? NO. First, let's look at what goes into a cup of bubble tea. There's tea, which contains caffeine, and less than 200mg of caffeine a day is okay if you're pregnant. There's milk, which is good, but may be high in trans fats that can raise your cholesterol level. And then there's syrup, which is made from loads and loads of sugar — about six teaspoons per cup, according to healthworks.my. The carbohydrates in tapioca pearls can also cause your blood sugar to spike.