In addition to 'domestic' adoption worldwide approximately 40,000 children per year are moved between 100 countries through adoption. Despite the popularity of adoption there is a persistent concern that adopted children may be at heightened risk of mental health or adjustment problems. Researchers at the University of Minnesota in the U.S. studied 1,232 adolescents (11-21) comparing those who had not been adopted, those who had been 'internationally' adopted and those who had been adopted from within the U.S. Being adopted approximately doubled the risk of attention deficit disorder and oppositional defiant disorder. Compared to international adoptees domestic adoptees had higher odds of having a disruptive disorder. However, international adoptees were at higher risk of major depressive disorder and separation anxiety disorder.
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