The baby's brain continues to develop until the end of the pregnancy. Therefore, taking certain medications at any stage of pregnancy can have lasting effects on a child's learning or behavior. There is a lot of research into the possible causes of learning and behavior problems, such as autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). However, this is a very difficult area to study and there is currently limited scientific information on the subject.

A handful of studies have looked at the development, behavior and learning of children whose mothers took paracetamol during pregnancy. These studies are summarized as follows:

Research on ADHD-like behavior:

A small study of 4-year-olds showed no link between in-utero exposure to paracetamol and attention problems.

A large study of 3-year-olds suggests a possible link between exposure to paracetamol in utero for more than 28 days and higher activity levels.

A large study evaluating 5 - and 7-year-olds showed that those exposed to paracetamol in utero had a slightly increased chance of ADHD-like behavior.

Another study used two different tests to determine whether a group of children exposed to acetaminophen in utero were more likely to exhibit ADHD-like behaviors than children not exposed. While one test suggested that 7-year-olds exposed to paracetamol in utero might have a slightly increased risk of ADHD, another test showed no increased risk at that age. When the children were retested at age 11, both tests agreed that there was no link between paracetamol use during pregnancy and an increased risk of ADHD. However, when kids in this age group were asked about their own behavior, those exposed to acetaminophen were more likely than those who weren't to say they had certain behavioral problems that might be related to ADHD.

Another study found that five-year-olds who were exposed to paracetamol in utero were less likely to develop adhd symptoms than children who were not exposed to acetaminophen.

While a large study of 7-year-olds showed that those exposed to paracetamol in utero were more likely to develop ADHD and behavioral problems, closer analysis of the data showed that this could actually be due to factors in utero. Come home after birth. The scientific quality of the study was heavily criticized in letters published at scientific meetings and in scientific journals.