Conclusion
Although the evidence against caffeine during pregnancy is not conclusive. Doctors recommend to play safe by taking only a maximum of 200 mg of any form of caffeine a day. Green tea may be OK to drink in moderation because a cup typically contains less than 45 mg of caffeine, but you’ll want to check with your doctor to be sure.
References;
[1] https://www.healthline.com/nutrition/polyphenols
[2] https://medlineplus.gov/genetics/understanding/basics/dna/
[3] https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2010/08/moderate-caffeine-consumption-during-pregnancy
[4] https://www.leukaemia.org.au/blood-cancer-information/types-of-blood-cancer/childhood-blood-cancers/childhood-all/
[5] https://www.artfultea.com/tea-wisdom-1/types-of-herbal-tea-and-their-benefits
[6] https://www.fda.gov/