meaning women are typically advised not to consume more than 200 milligrams of caffein – or two averagecups of coffee – a day , yet a young subject field in the journalBMJ Evidence - base Medicineindicates that even this may cause harm to a foetus . After conducting a review of all the available evidence on the content , subject field author Jack James of Reykjavik University concludes that there is in fact no safe level ofcaffeinethat can be have during pregnancy .
To conduct his research , James analyzed the findings from 37 late observational sketch and a further 17 meta - analyses , all of which examined the possible inter-group communication between caffeine and electronegative pregnancy outcomes . These include miscarriage , miscarriage , low nativity weight , preterm birth , childhood ague leukemia , and childhood overweight and fleshiness .
The 37 observational studies yielded a total of 42 different findings , 32 of which supported the notion that have caffein during pregnancy significantly increase the risk of a negative outcome . Meanwhile , 14 of the 17 meta - analyses were “ unanimous ” in concluding that maternal caffein consumption is associated with high rates of abortion , stillbirth , downcast parentage weight , and childhood acute accent leukemia .
Overall , an association was found between caffein and all of the listed negative outcomes apart from preterm nativity . Crucially , findings indicated no minimum threshold of consumption below which these association were absent , meaning that no amount of caffeine is risk - liberal .
While further inquiry is needed for full determine how the caffeine harms foetus , it is already known that caffein readily cross the placenta . Furthermore , fetuses and newborn infant generally miss the enzymes that are required to metabolizecaffeine , which could part explain why they are so hard affected by it .
According to James , anticipative mothers have for decades been mislead about the dangers of caffeine during pregnancy , with much of the rap for this reside with the International Life Sciences Institute ( ILSI ) .
In his write - up , he explains how the ILSI was established by soft boozing manufacturing business in the previous seventies after the FDA threatened to supply a health warning to products containing caffein . When concerns were subsequently raised about the safety of caffeine duringpregnancy , the ILSI stick out the publishing of a raft of scientific papers depicting caffeine as safe while portraying any evidence to the contrary as flawed and unreliable .
