The number of gays and lesbians adopting children has nearly tripled in the past decade despite discriminatory rules in many states, according to an analysis of recent population trends.

"It's a stratospheric increase. It's like going from zero to 60," said Miami attorney Elizabeth Schwartz who has coordinated more than 100 adoptions for gay and lesbian families in the past year. "I think many really dreamed of doing this but it wasn't something they ever thought would become a reality."

About 21,740 same sex couples had an adopted child in 2009, up from 6,477 in 2000, according to the Williams Institute, UCLA School of Law. About 32,571 adopted children were living with same sex couples in 2009, up from 8,310 in 2000. The figures are an analysis of newly released Census Bureau estimates.

New York-based Evan B. Donaldson Adoption Institute released a report Thursday culminating a four-year project surveying 158 gay and lesbian parents and their experience with the adoption process. Their researchers found the highest number of homosexuals adopted children from Massachusetts, California, New York and Texas.

Tom Bourdon, 35, and his husband interviewed more than a dozen private adoption agencies when they began the adoption process two years ago. The Massachusetts couple found some agencies "didn't really have experience working with a same sex couple and didn't how to treat us equally."

Once they settled on an agency, the couple created a profile that was open about their sexual orientation and desire to create a family. The couple, who were married in 2005, were matched with a birth mother five weeks later. They adopted their son in 2009 and a daughter eight days ago. Both children were born in California.

"We just wanted to be treated like any other prospective parent out there. We didn't want it to be an issue," said Bourdon, who works in education.

Several states specifically prohibit same-sex couples from adopting jointly, while others have a patchwork of discriminatory policies that make it difficult for gays and lesbians to adopt either as individuals or as couples. But some states have eased restrictions on gay families.

Florida stopped enforcing its ban on gay adoptions last year following a decision by a state appeals court that the three-decade-old law is unconstitutional. The American Civil Liberties Union challenged the law, among the strictest in the country, on behalf of Martin Gill and his male partner, who adopted two young brothers from foster care.

In the past, adoption was often only an option for wealthy gay families who could afford to adopt internationally or to pay a surrogate. Allowing gay couples to adopt from foster care, where health care and college is paid for, opens it up to more people, experts say. The study estimates about 50 percent of adoptive gay families adopt children from foster care.

Earlier this year, the Arkansas Supreme Court rejected a voter-approved initiative that barred gay couples and other unmarried people living together from serving as adoptive or foster parents

Virginia allows married couples and single people to adopt or become foster parents, regardless of sexual orientation, but bars unmarried couples _ gay or straight _ from doing so. Earlier this month, hundreds of residents weighed in on proposed regulations that would allow state-licensed groups to turn down prospective adoptive and foster parents because of their sexual orientation.

According to the Adoption Institute, at least 60 percent of U.S. adoption agencies surveyed accept applications from non-heterosexual parents. Nearly 40 percent of agencies have knowingly placed children with gay families. About half the agencies surveyed reported a desire for staff training to work with such clients.

But some adoption agencies have been bucked the rules, saying it's unfair to force them to go against their religious beliefs by coordinating adoptions for gay families.

Catholic Charities refused to recognize Illinois' new civil unions law and allow gay couples and others living together outside marriage to be foster or adoptive parents. The state tried to end its multimillion dollar contracts but a judge temporarily allowed Catholic Charities to work with the state.

"If one agency doesn't serve you and you're gay, then another agency will," said Adam Pertman, executive director of the Adoption Institute. "You don't need 100 percent agency participation. The bottom line is if you're a qualified gay or lesbian in America and you want to adopt, you can."

About one-third of the adoptions by lesbians and gay men were "open," and the birth families' initial reactions regarding sexual orientation were very positive, according to the study.

At California's Independent Adoption Center, executive director Ann Wrixon has seen a spike in LGBT couples adopting. In the past five years, gay families have consistently made up about one-third of the 200 adoptions a year.

Wrixon's agency is licensed in seven states and works with adoption agencies all over the country to find baby matches for clients. Ten years ago, she estimates only 25 agencies nationally were willing to work with gay families.

"We would often struggle to find agencies that would work with our families," said Wrixon.

Now she has a database with more than 125 agencies.

While the number of gay couples adopting is increasing, the overall number of same sex couples raising kids is actually declining, said Gary Gates, demographer at the Williams Institute, UCLA School of Law.

"The bulk of parenting among gay people is still people who had children at a young age with a different sex partner before they were out," said Gates.

Now that many homosexuals are coming out earlier in life, they're having fewer biological children and are more likely to turn to adoption to start a family, he said.