Women who drink tea or coffee during pregnancy are more likely to have young children, research suggests. Even women who…
Even women who drink less than the “safe” cutoff of 200mg caffeine – about two cups of instant coffee or three cups of tea – risk having low birth weight or premature newborns.
The researchers from University College Dublin believe that caffeine limits blood flow to the placenta and affects children’s growth. The study was led by Dr. Ling-Wei Chen, looked at 941 mother-in-law couples born in Ireland. Tea was the main source of caffeine (48 percent), followed by coffee (38 percent).
Results suggested that for each additional 1
00 mg caffeine – about half a cup of coffee is consumed daily during the first trimester, birth weight decreased by 72 kg.
This amount of caffeine also reduced the length and the circumference of the children, as well as their gestation period, which measures the length of pregnancy. The results further found that the women who consumed the most caffeine had children weighing about 0.37 kg (170g) less than those who had the least.
Even women who received less than the “safe” amount of 200 mg caffeine saw significant effects. This amount is considered to be safe by NHS.
The study was published in The American Journal of Clinical Nutrition.
Dr. Chen told Reuters: “Due to the consistent associations we observed, and because many pregnancies are imperfect, we recommend that women who are pregnant or want to conceive at least limit their intake of caffeine-free coffee and tea.” High caffeine intake can result in limited blood flow in the placenta, which can subsequently affect the growth of the fetus.
Caffeine can also easily pass the placenta, and since caffeine clearance slows when pregnancy progresses, caffeine accumulation can occur in fetal tissues. & # 39;
The researchers worry that people do not know how much caffeine their tea contains.
To have less caffeine than a cup of coffee, but the exact amount depends on brewing time, water temperature and type of tea.
The Department of Nutritional Services reports that a cup of black tea contains somewhere between 23 and 110 mg of caffeine.
The World Health Organization recommends that women consume less than 300 mg of caffeine a day during pregnancy. NHS and the American College of Obstetricians and Gynecologists do not recommend more than 200 mg.
But the latest survey indicates that this is too high, according to Dr De-Kun Li, a researcher at the Kaiser Permanent Northern California Research Department in Oakland.
He was not involved in the study but found a link between caffeine consumption during pregnancy and miscarriage in a study in 2015.
Epidemiological findings based on self-reported caffeine consumption are usually not very precise. Thus, any cutoffs chosen by ACOG and WHO can only be considered as gross reference points, says Dr. Li.
& # 39; Biologically it is unlikely that 300 mg is risky while 299 mg is safe. The message to women I prefer would be “the less the better”.
“My advice would try to reduce as much as you can, if you can completely stop it would get even better.”
ACOG added that it reviews all its recommendations every 18-18 months, contains all new research in its reviews and adjusts recommendations as needed.
In 2008, a trial of 1,063 pregnant women in San Francisco showed that those who consume at least 200 mg of caffeine each day have 25 percent risk of miscarriage compared to a 12 percent risk for those who avoid stimulation, which is also in soda and chocolate.
Another study showed caffeine consumption during pregnancy seems to promote childhood fatness. The daily record.