Several factors affect the decision to release or raise the child. White adolescents tend to give up their babies to non-relatives, whereas black adolescents are more likely to receive support from their own community in raising the child and also in the form of informal adoption by relatives. Studies by Leynes and by Festinger and Young, Berkman, and Rehr found that for pregnant adolescents, the decision to release the child for adoption depended on the attitude toward adoption held by the adolescent's mother. Another study found that pregnant adolescents whose mothers had a higher level of education were more likely to release their babies for adoption. Research suggests that women who choose to release their babies for adoption are more likely to be younger, enrolled in school, and have lived in a two-parent household at age 10, than those who kept and raised their babies.
Ad hoc studies, performed in the U.S., however, suggest that between 10 and 25 percent of adoptions through the child welfare system (e.g., excluding babies adopted from other countries or stepparents adopting their stepchildren) disrupt before they are legally finalized and from 1 to 10 percent are dissolved after legal finalization. The wide range of values reflects the paucity of information on the subject and demographic factors such as age; it is known that teenagers are more prone to having their adoptions disrupted than young children.
Other studies provide evidence that adoptive relationships can form along other lines. A study evaluating the level of parental investment indicates strength in adoptive families, suggesting that parents who adopt invest more time in their children than other parents and concludes, "...adoptive parents enrich their children's lives to compensate for the lack of biological ties and the extra challenges of adoption." Another recent study found that adoptive families invested more heavily in their adopted children, for example, by providing further education and financial support. Noting that adoptees seemed to be more likely to experience problems such as drug addiction, the study speculated that adoptive parents might invest more in adoptees not because they favor them, but because they are more likely than genetic children to need the help.
The practice of closed adoption (aka confidential or secret adoption), which has not been the norm for most of modern history, seals all identifying information, maintaining it as secret and preventing disclosure of the adoptive parents', biological kins', and adoptees' identities. Nevertheless, closed adoption may allow the transmittal of non-identifying information such as medical history and religious and ethnic background. Today, as a result of safe haven laws passed by some U.S. states, secret adoption is seeing renewed influence. In so-called "safe-haven" states, infants can be left, anonymously, at hospitals, fire departments, or police stations within a few days of birth, a practice criticized by some adoption advocacy organizations as being retrograde and dangerous.
In the 1970s, as adoption search and support organizations developed, there were challenges to the language in common use at the time. As books like Adoption Triangle by Sorosky, Pannor and Baran were published, and support groups formed like CUB (Concerned United Birthparents), a major shift from "natural parent" to "birthparent" occurred. Along with the change in times and social attitudes came additional examination of the language used in adoption.