Most Herbal Tea products are not Tea
Regular teas are actually made with leaves from a warm-weather evergreen tree known as Camellia sinensis. Most herbal teas on the market place are not tea at all. They are only infusions made with herbs, flowers, roots, spices or other parts of plants. The proper term for this type of beverage is "tisane". Since herbal infusions do not contain tea leaves, they are therefore caffeine free.
Since herbal tea does not contain tea leaves and tea leaves are the only ingredient containing polyphenols (a type of antioxidant), drinking herbal tea does not have the particular health-promoting properties associated with drinking regular tea. Although herbal infusion does not contain as much polyphenols, it does promote other various health qualities such as relaxation and calming effects.
Herbal Tea during Pregnancy
Some herbal teas are safe to drink during pregnancy. These include citrus peel, ginger, lemon balm, orange peel and rose hip teas. However some other herbal teas may have pharmacological properties. Chamomile tea, for instance, have been reported to have adverse effects on the uterus; therefore avoid chamomile tea during pregnancy. Since there are various herbal tea products available and no standard labeling policies have been imposed, it is generally advised that herbal teas should be taken only in weak infusion and used in moderation during pregnancy.