Two universities in the UK have determined that excessive amounts of caffeine during pregnancy can impact the weight of the child as it’s developing, putting some babies at risk of a low birth weight.

What do we mean by excessive? Well, the study found that the babies of mothers who drank the equivalent of 3 or more cups of coffee each day tracked to a lower weight during each trimester of development. A low birth rate has been linked to health issues such as diabetes or heart disease later in life, so it’s important that a baby is born within the healthy range.

While the study has confirmed a link between caffeine and fetal development issues, scientists don’t think this should inspire pregnant mothers to abstain from all caffeine intake. Other health benefits still exist and a mother limiting her coffee to 1 cup per day should have no concern.