A new study has pinpointed steps that a pregnant woman can take that can reduce the risk of giving birth to a child with attention-deficit hyperactivity disorder (ADHD). The condition is a behavior disorder, usually first diagnosed in childhood, which is characterized by inattention, impulsivity, and, in some cases, hyperactivity. Australian researchers published the results of their study online on December 2 in the journal Pediatrics.
The investigators that an increasing number of studies are being conducted on early environmental risk factors for a child developing ADHD. They conducted a study that evaluated maternal, pregnancy, and newborn risk factors for children prescribed stimulant medication for treatment of ADHD in Western Australia. The investigators also looked for any gender differences in the risk factors.
The study group comprised 12,991 non-Aboriginal children and teens born in Western Australia that were younger than 25 years who were diagnosed with ADHD and prescribed stimulant medication. The records of all the subjects were combined with data from the Midwives Notification System (MNS) to obtain maternal, pregnancy, and birth information. These children were compared to 30,071 children who were randomly selected from the MNS.
The investigators found that the mothers of children with ADHD were significantly more likely to be younger, be single, have smoked during pregnancy, had their labor induced. They also were more likely to have experienced threatened preterm labor, preeclampsia (toxemia), urinary tract infection in pregnancy, or early term delivery. Except for a possible protective effect of induced labor in girls, no significant gender differences were found. The following were not found to be risk factors for ADHD: low birth weight, post-term pregnancy, small for gestational age infant, fetal distress, and low Apgar scores.
The authors concluded that smoking during pregnancy, maternal urinary tract infection, having had labor, and experiencing threatened preterm labor increase the risk of ADHD, with minimal gender difference; however, oxytocin augmentation of labor appeared to be protective for girls. Early term deliveries slightly increased the risk of ADHD. They recommended that further studies be conducted that focused on clarifying possible mechanisms, confounders (factors that could skew the results), or moderators of these risk factors.
ADHD is one of the most researched areas in child and adolescent mental health. It is a brain-based biological disorder. Low levels of dopamine (a brain chemical), which is a neurotransmitter (a type of brain chemical), are found in children with ADHD. Brain imaging studies using PET scanners (positron emission tomography; a form of brain imaging that makes it possible to observe the human brain at work) show that brain metabolism in children with ADHD is lower in the areas of the brain that control attention, social judgment, and movement.
Estimates of the prevalence of ADHD range from 4% to 12% of children. Boys are two-to-three times more likely to have ADHD than girls. Many parents of children with ADHD experienced symptoms of ADHD when they were younger. ADHD is commonly found in brothers and sisters within the same family. Most families seek help when their child's symptoms begin to interfere with learning and adjustment to the expectations of school and age-appropriate activities.
The following are the most common symptoms of ADHD. However, each child may experience symptoms differently. The three categories of symptoms of ADHD include the following:
- Short attention span for age (difficulty sustaining attention)
- Difficulty listening to others
- Difficulty attending to details
- Easily distracted
- Poor organizational skills for age
- Poor study skills for age
- Often interrupts others
- Has difficulty waiting for his or her turn in school and/or social games
- Tends to blurt out answers instead of waiting to be called upon
- Takes frequent risks, and often without thinking before acting
- Seems to be in constant motion; runs or climbs, at times with no apparent goal except motion
- Has difficulty remaining in his/her seat even when it is expected
- Fidgets with hands or squirms when in his or her seat; fidgeting excessively
- Talks excessively
- Has difficulty engaging in quiet activities
- Loses or forgets things repeatedly and often
- Inability to stay on task; shifts from one task to another without bringing any to completion
The symptoms of ADHD may resemble other medical conditions or behavior problems. Bear in mind that many of these symptoms may occur in children and teens who do not have ADHD. A key element in diagnosis is that the symptoms must significantly impair adaptive functioning in both home and school environments. Always consult your child's doctor for a diagnosis.