A growing number of reproductive-age women are taking prescription medication to treat attention-deficit/hyperactivity disorder (ADHD), data show, but doctors warn the effects of such drugs on pregnancies are largely unknown. The number of privately insured women nationwide between the ages of 15 and 44 who filled a prescription for an ADHD medication soared 344 percent from 2003 to 2015, from 0.9 percent to 4 percent, according to Centers for Disease Control and Prevention (CDC). ADHD medication use increased among all age brackets within that group and in all geographic regions, data show. The biggest spikes were seen in women ages 25 to 29, among which medication use jumped 700 percent, from 0.5 percent in 2003 to 4 percent in 2015. The second-largest increase was among women ages 30 to 34, which had a 560 percent increase from 0.5 percent to 3.3 percent, according to the CDC.