Premature birth linked to increased risk of ADHD

Babies conceived just one month premature will probably create attention deficit hyperactivity disorder (ADHD) in later life, new research suggests.

Researchers in Norway compared a group of children born prematurely with a control group of children born at full term to see if either was more likely to develop symptoms of ADHD, such as hyperactivity and reduced attention span, at pre-school and school age.

Babies are considered to be full term if they are born at 37 weeks or later into the pregnancy. Before this, they're considered premature.

ADHD is a complex condition, and its causes are not fully understood. Environmental factors – such as whether a child was born prematurely – and genetics are thought to play a role.

While there is no guaranteed method of preventing premature birth, mums-to-be can reduce their risk by staying active, and avoiding drinking alcohol and smoking.

Results:

At age 5

The results from siblings suggested this effect was not solely caused by shared genetics or other unmeasured environmental factors.

At age 8

Children born early preterm had higher levels of inattention symptoms, but not hyperactivity or impulsivity.

ADHD symptoms were reported by the mothers and not verified by other observers. Mothers whose children were premature may have been more watchful for signs of ADHD, which could have influenced their ratings. It's also worth noting that this study had doctors assess the children to see whether any would qualify as having a diagnosis of ADHD.