Is there a link between adoption and depression?

There is no scientific evidence indicating that being adopted leads to Major Depressive Disorder, either in childhood and adolescence or as an adult. But based on what medical professionals believe are some of the causes of the disorder, it appears that adoption could lead to depression in some people.

Currently, little research is dedicated specifically to the effect of adoption on a person's likelihood of suffering from depression. In a study published by the National Institutes of Health, researchers found no difference in the rate of depression between adopted and nonadopted adolescent subjects. In fact, members of each group were more likely to suffer from MDD if either of their parents (adopted parents in the case of adoptees) also suffered from it. The rate of parental depression did not vary significantly between adoptive and nonadoptive families [source: Tully]. Researchers at Stanford and Harvard universities have also noticed a strong link between depression in adoptive children and their biological parents, finding that an adopted person's risk of depression is higher if one of his or her biological parents has also suffered from depression [sources: Levinson, Harvard University].

Although none of these studies indicates that being adopted makes a person more likely to suffer from MDD either as a child or an adult, there are nevertheless certain environmental factors thought to cause depression that could be brought on by virtue of being adopted. Specifically, doctors cite a person's failure to establish solid emotional bonds in infancy because of rejection or neglect (which could be a byproduct of being put up for adoption or living in foster homes for an extended period of time) as one of many possible sources of depression [source: University of Alabama]. Of course, this and many additional factors believed to cause depression can be linked to a number of other biological and environmental issues that are in no way related to adoption. In other words, while adoption could lead to depression, there is no hard evidence that it does.

So what about other psychological and behavioral disorders? Are adoptees more likely than others to develop them? Check out the next page to see what the experts say.

Depression isn't the only psychological illness to encompass people from all walks of life. Almost 4 percent of U.S. adults suffer from bipolar disorder. Also called manic-depressive disorder and manic depression, a person with this condition swings between bouts of clinical depression and mania (a state of elevated irritability and energy that is essentially the opposite of depression). While most people who experience mania are also clinically depressed, the majority of people with depression do not also have episodes of mania [source: Levinson].

Bipolar disorder, like MDD, appears to be largely a result of genetics. Specifically, a number of adoption studies have shown that biological relatives of bipolar patients are substantially more likely to have the disorder than are adoptive relatives. While a major life change may trigger a manic or depressive episode in someone with the condition, biology appears to be the root cause of bipolar disorder. However, there is no evidence suggesting that an adopted person with bipolar disorder has the illness due to the mere fact that he or she is adopted [source: National Library of Medicine, Taylor].

Adoption may not increase a person's risk of psychological disorders, but it can lead to behavioral problems. Attention Deficit Hyperactivity Disorder (ADHD) -- distinguished from general misbehavior as a pattern of hostile, aggressive or disruptive behavior lasting six months or more -- affects somewhere between 5 and 9 percent of American children. With symptoms varying from inattentiveness to hyperactivity and impulsive actions, the causes of ADHD are difficult to pinpoint. There is a strong suggestion that the disorder can be inherited: 40 percent of children with ADHD will have a parent with ADHD [source: Adesman]. Nevertheless, a 2008 study published in the Archives of Pediatric and Adolescent Medicine indicates that although most adopted children are psychologically healthy, they are subject to "slightly increased risk" of ADHD; 15 percent of the adopted children studied suffered from ADHD, roughly twice the rate of the nonadopted subjects [source: Trudeau].

Want more information on adoption and behavioral issues? Check out the links on the next page.