Green tea is considered a non-herbal tea and contains a lot more caffeine than herbal tea. So, one of the things to consider is that drinking a lot of green teas will contain a lot of caffeine. Pregnant women who consume more than 4 or 5 cups of coffee a day have double the risk of miscarriage per a study from the Northern California Division of Research Kaiser Permanente division. The best green tea brands will also contain a lot of caffeine. This is compared to those that avoid the stimulant.
The study showed that caffeine increases the risk of a miscarriage when it is consumed in large amounts. So, it is best to use caution when you are drinking caffeine and especially if you are a woman that is pregnant. Caffeine is a substance that is released when the water is steeping, so to make the tea decaffeinated by steeping the leaves for about 30 seconds before dumping the water and refilling the cup with new hot water. That way most of the caffeine will be gone because it was in the old water. This is not just a tip that is best if you are a woman that is pregnant it is also a good tip if you want to lower your caffeine intake in general.