However, some experts disagree, saying the report is “alarmist” and a small amount of caffeine (about 200mg) is safe during pregnancy, the BBC reported.
The “narrative review” was published this week in BMJ by Jack E. James, a psychology professor at Reykjavik University in Iceland.
As the outlet wrote, the UK’s National Health Service (NHS), as well as other agencies, advises pregnant women to limit caffeine because too much can cause low birth weight, raising the risk for health issues later in life. NHS also says too much caffeine can lead to a miscarriage.
The report in BMJ examined 48 studies on maternal caffeine consumption, and the author wrote: “The articles reported results for one or more of six major categories of negative pregnancy outcomes: miscarriage, stillbirth, low birth weight and/or small for gestational age, preterm birth, childhood acute leukemia, and childhood overweight and obesity.”
According to the BBC, James recognizes his report is “observational” and cannot firmly “prove” caffeine brings negative consequences for pregnant women. Nevertheless, he reportedly says his work suggests pregnant women, and those considering pregnancy, avoid caffeine altogether.
Clinical guidance from the American College of Obstetricians and Gynecologists says “moderate caffeine consumption (less than 200 mg per day) does not appear to be a major contributing factor in miscarriage or preterm birth,” adding, “a final conclusion cannot be made at this time as to whether there is a correlation between high caffeine intake and miscarriage.”
The European Food Safety Authority and the UK College of Obstetricians and Gynaecologists also advise “limiting” but not completely avoiding caffeine intake while pregnant, the BBC reported.
One pharmacist told the BBC that the BMJ report did not align with “accepted evidence.” Dr. Luke Grzeskowiak, with the University of Adelaide in Australia, reportedly said the paper was “overly alarmist” and “inconsistent with accepted evidence.”
“There are so many dos and don’ts associated with pregnancy and the last thing we need is to cause unnecessary anxiety,” Grzeskowiak told the outlet. “At the end of the day, women should be reassured that caffeine can be consumed in moderation during pregnancy.”