A study says that one cup could put the unborn baby on a path to obesity.
Researchers in Norway studied 50,000 pregnant women over 11 years.
They found exposure to any caffeine level while in the womb was associated with a heightened risk of the child being overweight by age 3 and 5.
As with all medical decisions, if you are pregnant and wondering what to do now about coffee or other drinks with caffeine, consult with your doctor.