Pregnant? Skip the Tea, Take the Supplement? Or Maybe Not…
Green tea (Camellia sinensis) has been credited with improving health benefits for conditions as diverse as aging, cancer, inflammatory diseases, cardiovascular disease, autoimmune disorder, microbial infections and diabetes. The active ingredients in green tea are polyphenols in the catechin sub-group. The most noteworthy catechin in green tea is epigallocatechin gallate (EGCG) because it is present in the highest quantities in green tea and has been reported to be the most beneficial. There are many different green tea formulations being created and tested as replacements for drinking green tea, since the EGCG in tea is metabolized relatively quickly in the body. Most of the preparations do not contain caffeine. The following research results make it clear that extreme caution should be taken before using any herbal preparations, including things as seemingly safe as green tea.
Teavigo™
Teavigo™ is an EGCG preparation currently on the market that contains no caffeine. Researchers tested its effects on rat fetal development to evaluate potential effects of EGCG on the fetus.1 Teavigo, containing more than 91% pure EGCG was administered to gestating rats during organ creation and development. To study the potential of EGCG causing birth defects, pregnant rat diets were supplemented with 1400, 4200 or 14,000 mg EGCG per kilogram of rat weight. Mothers and fetuses showed no signs of toxicity at any concentration of EGCG. In a two-generation study, rats were fed 1200, 3600 or 12,000 mg EGCG per kilogram of food and there were no detrimental effects on reproduction or fertility. The 12,000 mg EGCG treatment resulted in reduced growth rate of offspring and a slight increase in rat pup mortality. Reduced growth rate was also observed at the 3600 mg EGCG per kilogram of food rate in the second generation of rats.
Green Tea Extract
Another herbal preparation is green tea extract (GTE) that comes from steeping a strong tea and washing the leaves with alcohol to ensure complete removal of catechins from the leaves. Scientists reported in 2009 results of a study testing the effect of GTE on incidence of birth defects in a rat model treated with a teratogenic amide.2 Pregnant rats were given 100 mg GTE per kg of rat weight from days 6-12 gestation. A cyclophosphamide was given to the pregnant rats 1 hour after the last GTE treatment, at a dose of 11 mg per kg rat weight.
Pregnancy was stopped on the 20th day gestation and maternal and fetal defects were determined following Cesarean birth of the pups. Fetal and placental weights were depressed. More significantly, 95% of live fetuses exhibited skull and limb defects, 41% had cleft palate and ureteric dilation and 100% had skeletal abnormalities. Repeated dosage of GTE during pregnancy can lead to birth defects and reduced fetal and placental weights.
As always, its crucial to consult with your healthcare provider before ingesting any non-food preparations, including items like green tea that are generally regarded as safe by the US Food and Drug Administration.
1Safety studies on epigallocatechin gallate (EGCG) preparations. Part 3: Teratogenicity and reproductive toxicity studies in rats, Isbruckera, RA; Edwards, JA; Wolzb, E; Davidovichc, A and Bauschb, J. Food and Chemical Toxicology. 2006. 44(5): 651-661.
2Green tea extract increases cyclophosphamide-induced teratogenesis by modulating the expression of cytochrome P-450 mRNA. Park D, Jeon JH, Shin S, Joo SS, Kang DH, Moon SH, Jang MJ, Cho YM, Kim JW, Ji HJ, Ahn B, Oh KW, Kim YB. Reprod Toxicol. 2009. 27(1):79-84.
