Two new studies on attention deficit hyperactivity disorder (ADHD) medications during pregnancy are out. Both studies conclude that the benefits of ADHD medications may outweigh the risks of untreated ADHD during pregnancy for some women. Both studies were published in 2017, one in the journal Pediatrics and the other in Obstetrics & Gynecology. 
These studies finally give doctors and women with ADHD some data to work with when deciding if they should go off ADHD medications during pregnancy or continue treatment. This has always been a difficult decision. There has been very little data on how ADHD medications affect pregnancy. There is also very little data on how untreated ADHD affects pregnancy. So, weighing the risks versus benefits has been a bit of a dilemma. [2,3]
Adult ADHD Basics
Attention-deficit/hyperactivity disorder (ADHD) is usually thought of as a childhood mental health disorder. Today we know that most children with ADHD – about 70 percent – grow up to be adults with ADHD. In fact, between four and five percent of U.S. adults are diagnosed with ADHD. Many of these adults are women in their childbearing years. [1,2]
To diagnose adult ADHD, symptoms of ADHD must have been present before age seven. The symptoms must be severe enough to cause problems in social situations, at home, at work, or at school. Doctors also need to rule out other possible causes of the symptoms. Symptoms of adult ADHD can include [2,4]
- Problems focusing, planning, and multitasking
- Mood swings
- Low frustration tolerance
- Low stress tolerance
ADHD Medications and Pregnancy
Medications are very effective for treating adult ADHD. The most common medications are the stimulant drugs amphetamine and methylphenidate and the nonstimulant drug atomoxetine. All of these drugs are category C drugs during pregnancy. That means that there is no evidence of harm during pregnancy, but no evidence of safety either. 
Until these two recent studies, there was very little data on how stimulant drugs used to treat ADHD affect pregnancy. There was almost no data on the effect of atomoxetine. The few available studies gathered data from women who were pregnant and abusing amphetamines. These studies suggest these possible risks to pregnancy from stimulant drugs: [2,3]
- Low infant birth size and weight
- Premature birth
- Cesarean section birth
- Low infant Apgar scores
Untreated ADHD and Pregnancy
There is no specific research on how untreated ADHD affects a pregnancy. However, we do know how untreated ADHD can affect adults in general. Many of these effects would pose a risk during pregnancy. They include: [1,2]
- Poor attention, which could mean poor attention to prenatal care
- Unhealthy lifestyle, which could mean poor nutrition or poor sleep
- Emotional stress, which could lead to physical stress on a developing baby
- A higher risk for substance abuse, which could be toxic for a developing baby
- A higher risk for depression and anxiety, which could have negative impact on a pregnancy
What the Studies Found
The Pediatrics study was from Sweden. It included close to one million births between 2006 and 2014. The purpose of the study was to gather data on how prescription drugs affect pregnancy. Of these birth, 1,464 women were taking ADHD stimulant prescriptions and 165 were taking atomoxetine. 
In the Obstetrics & Gynecology study, researchers from the Harvard School of Public Health looked at the records of about 1.5 million women on Medicaid to find women who were taking prescription ADHD drugs during pregnancy. They found 4,846 women on stimulants and 453 on atomoxetine. 
These are the first studies to look at significant numbers of pregnant women on ADHD medications and compare them to women not taking these medications. The good news is that they found very few problems. Compared to the women not taking ADHD medications, there was only a slight increase in maternal high blood pressure (preeclampsia) and preterm births for the women taking ADHD medications. 
The researchers from both studies concluded that continuing ADHD medication during pregnancy added a modest risk, but withholding these medications was not justified if untreated ADHD might result in poorly controlled ADHD symptoms. They agree that poorly controlled ADHD may be a greater risk than medication treatment. 
What Should You Do?
If you are a young woman on an ADHD drug, and you are thinking about pregnancy, the best time to talk to your doctor about your medication is before you get pregnant. This is called preconception counselling. During counselling, you should weigh the risks and benefits of continuing treatment or stopping. If you decide to stop medication, you can start a slow taper. Stopping medication suddenly is dangerous and can lead to withdrawal symptoms. [1,2]
As you taper your medication, you can try non-medication ADHD treatments. These include working with a therapist or an ADHD coach. If you are doing well without medication, you can go ahead with your pregnancy drug free. If you are struggling, you can go ahead with pregnancy and medication. It will be important to make your ADHD provider part of your pregnancy care team. [1,3]
If you become pregnant while on ADHD medication, let your doctor know right away. You can start the risk befits discussion as soon as possible. There is no reason to fear that your pregnancy or your baby is in danger. The most important thing is not to let uncontrolled symptoms of ADHD affect your pregnancy. If you need medications to do that, the studies suggest that’s the best way to go. 
- Medscape, ADHD Drugs Associated With Modest Risks During Pregnancy.
- Psychiatry Advisor, A Case Study on the Treatment of ADHD in Pregnancy.
- Medscape, Treating ADHD During Pregnancy.
- Mayo Clinic, Adult attention-deficit/hyperactivity disorder (ADHD).