A study on adoption patterns carried out by a team of economists has revealed that US parents prefer to bring home girls over boys, and non-black children over African-Americans.
The team from the California Institute of Technology, the London School of Economics and New York University studied five years worth of data from 2004-2009 culled from a website run by an adoption intermediary.
They were able to see which babies attracted most applications from adoptive parents, and how much the parents would need to pay to finalize the adoption.
They found that a non-African-American baby was seven times more likely to "attract the interest and attention of potential adoptive parents than an African-American baby," said Leonardo Felli, an economics professor at LSE.
But there was not a similar preference in favor of Caucasian babies over Hispanic babies, even though all the adoptive parents in the sample were Caucasian, Felli said.
The research also uncovered a unexpectedly strong preference in favor of girls, which were a little over a third more likely to attract the attention of adoptive parents than a boy, he said.
"With biological children, the literature shows that there's a slight but significant preference for boys over girls," said Leeat Yariv, an associate professor of economics at Caltech. "But in adoption, there's a very strong preference for girls over boys."
The bias in favor of girls and non-black children was seen across all categories of adoptive parents, and the gender bias against boys was even slightly stronger among gay men and lesbian couples seeking to adopt a child.
The study also found that interest in a child was highest just before birth, but dropped off dramatically immediately afterwards and was also low when the birth mother was still in the early stages of pregnancy.
Mariagiovanna Baccara, an assistant professor at NYU, said it suggested that "bureaucratic obstacles disrupting an adoption plan at the time of birth are extremely detrimental to the future prospects of the child."
Felli said the adoption system in the United States remains doubly imbalanced.
"On the one hand, a considerable number of potential adoptive parents are left unmatched. On the other hand, the number of children who are not adopted and end up in the foster-care system is disproportionately high."
The researchers said their data showed that obstacles to adoption of US children by gay couples or foreigners stood to significantly increase the number of children who would end up in foster care after failing to find an adoptive family.
"And statistically," Yaariv added, "long-term foster care leads to bad outcomes."