While green tea is generally considered safe for most people, it's important for pregnant and breastfeeding women to be cautious about their caffeine intake, including from drinking Kirkland green tea. The American College of Obstetricians and Gynecologists recommends that pregnant women limit their caffeine intake to no more than 200 milligrams per day, which is roughly equivalent to one 12-ounce cup of coffee. Green tea contains caffeine, although the amount can vary depending on the type and brewing method. On average, an 8-ounce cup of green tea contains between 20-45 milligrams of caffeine. In addition to caffeine, green tea also contains compounds called catechins, which may have potential health benefits but can also interfere with certain medications and may have some risks during pregnancy. Some studies have suggested that high levels of caffeine and catechins may be harmful to developing fetuses, so pregnant and breastfeeding women should speak with their healthcare provider before consuming green tea or any other caffeinated beverages.