Caffeine and Birth Weight

How much caffeine during pregnancy is too much? Studies on the subject have put the limit of safe consumption at varying levels, say researchers from the CARE Study Group. They cite one study that found significant reduction in infant birth weight when women ingested more than 141 mg/day and others that concluded that, while more than 300 mg/day might be associated with such poor outcomes as low birth weight, the evidence was too scanty to make a definite judgment.