Caffeine/herbal teas
The issue: Caffeine can cross the placenta and affect fetal heart rate and respiration. Certain herbs cause adverse reactions, and some teas are not regulated, so you can't be sure of the herb's concentration.
What's okay: Up to 300 mg of caffeine a day (an 8-ounce cup of coffee has about 150 mg, a 12-ounce can of soda has 35 to 50 mg, and an 8-ounce cup of black tea has about 40 mg); flavored decaffeinated teas in filtered bags (citrus, ginger, peppermint).
What to avoid: Teas made with goldenseal, black or blue cohosh, ephedra, dong quai, feverfew, juniper, pennyroyal, Saint-John's-wort, rosemary, or thuja.
