Editor's note: In this series, CNN investigates international adoption, hearing from families, children and key experts on its decline, and whether the trend could -- or should -- be reversed.

Hong Kong (CNN) -- In April 1999, Laura Blitzer -- a 41-year-old single university professor -- decided to adopt a child. Fifteen months later the native of Brooklyn, New York, was in Hunan Province, China, holding her 9-month-old adoptive daughter, Cydney, for the first time.

"It was amazing to have her in my arms ... I still cry when I see the tape of her being given to me," recalled Blitzer. "I couldn't believe she was mine."

In 2007, Blitzer applied to adopt another child from China. Six years later, she is still waiting. "The estimate right now for me to receive a healthy infant is 2017," she said.

After decades of steady growth, the number of international adoptions has dropped nearly 50% since 2004, despite the well-publicized explosion of adoptions from China in the 1990s, and high-profile adoptions by celebrities such as Angelina Jolie from Cambodia and Madonna from Malawi.

The decline isn't due to fewer orphans worldwide nor waning demand from prospective parents, experts say. It is due to rising regulations and growing sentiment in countries such as Russia and China against sending orphans abroad.

The number of children finding new homes in the United States -- the number one location for adopting children -- fell to 8,668 in 2012 after peaking at 22,884 in 2004, according to U.S. State Department statistics. A survey by Britain's Newcastle University of the top 23 nations that adopt children from abroad recorded 23,626 international adoptions in 2011 -- down from 45,299 in 2004.

"I think it's both a surprise that it's been dropping, and it's a surprise that significant forces are opposed to international adoption," said Elizabeth Bartholet, professor of law and director of the Child Advocacy Program at Harvard Law School. With the growing forces of globalization, "why wouldn't this be expanding?" added Bartholet, a proponent of international adoption who adopted two boy from Peru in the 1980s.

As international adoption rates fall, there is one country that is sending more children abroad: The United States.

International adoptions rising -- for American black children

Although the number of American kids adopted internationally is far fewer than overseas orphans that join U.S. families, with 315 children in 2009 that's three times as many as 2004, according to Newcastle University.

"No country likes that it's not tending to all of its own children. And I think a lot of Americans are surprised that we are one of those sending countries," said Adam Pertman, Executive Director of the Donaldson Adoption Institute and author of "Adoption Nation."

Feeding the 'adoption nation'

The story of international adoption is an American story.

"The United States adopts more children internationally, but also domestically, than the rest of the world combined," Pertman said. "The good, the bad and the ugly all play out here in bigger ways than they do elsewhere simply because the process is older and more developed here, for better or for worse."

Laura Blitzer with her daughter, Cydney, adopted from China in 2000. Blitzer has waited six years to adopt a second child.

 

Transnational adoptions grew in popularity following the World War II -- at least 50,000 took place from 1948 to 1969.

With the opening of China and Russia in the 1990s, international adoption exploded -- 410,000 children were adopted by citizens of 27 countries between 2000 and 2010, according to Peter Selman, an international adoption expert from Newcastle University and statistical adviser to the U.N. Hague Convention on international adoption.

"In Russia it was the breakup of the Soviet Union. In China it was the discovery of the impact of the one-child policy," said Susan Caughman, publisher of Adoptive Families Magazine, who adopted a daughter from China in 1992.

"Chinese orphanages then were stuffed with abandoned infants," largely girls, Caughman said, as boys were preferred by families after the implementation of the one-child policy. "Russia was on its knees in a catastrophic situation as the social fabric unraveled."

Feeding the trend were single, career-minded U.S. women like Blitzer.

"I'd never been married and went up and down the East Coast to get various degrees ... I like to work. Working is a big part of who I am," said Blitzer, a professor of health and physical education.

But she also wanted a family. A few months after Blitzer filed paperwork to adopt, a 13-day-old girl was left in a market in Shaoyang, China, with the name Shao Zhi Ying written on a piece of paper.

"That means 'wisdom' and 'courage' -- they must have known something, because that's exactly who she is," Blitzer said. As per regulation, the police placed a "finding ad" in a local newspaper detailing the abandoned child and placed her in the Shaoyang Welfare Institute orphanage. Nine months later, she was in the arms of Blitzer, who named her new daughter Cydney.

Now 13, Cydney Blitzer is starting her freshman year at the LaGuardia High School for Music and Art and the Performing Arts -- the inspiration for the movie "Fame."

"She's fiercely independent, very quick and talented, and she's got a fantastic voice," said her mother, who now works in the Department of Kinesiology at Brooklyn College in New York.

From abandoned infant in a Chinese market to acceptance into a world-renowned school in New York, the Blitzers could be a poster family for the rags-to-riches aura that cloaks the spirit of international adoption: Individuals and families opening their lives to the world's most underprivileged orphans.

Abandoned at a Chinese market just a few days old, 13-year-old Cydney has entered the prestigious LaGuardia High School.

 

"(Adoption) captures people's imagination ... it's right out of Charles Dickens; it's a dramatic story, an archetype of literature," Caughman said.

But as Blitzer found when she filed to adopt another child from China six years ago, these fairy tale endings are now less common.

Door to China narrows

If Blitzer, now 55, filed for adoption in China today, she would have no hope of being matched with a healthy baby. In May 2007 -- a month after she filed for her second adoption -- China instituted new, stringent rules for foreign adoptions. The new rules at first prohibited single people and those over the age of 50 from adopting a child. In 2011, single women were again allowed to adopt but only children with special needs, such as those with a physical disability. Single women must sign an affidavit that they are not homosexual.

China also now prohibits adoptions to foreigners who are morbidly obese or have facial deformities. People who have taken antidepressants for serious mental disorders in the past two years are also not eligible, as are applicants who are blind, have schizophrenia or a terminal disease. Couples must be married at least two years, unless either person has been previously divorced -- in which case they aren't eligible to adopt until five years after their wedding. China also now requires prospective families to have an annual income equal to $10,000 per family member and at least $80,000 in assets.

The new rules were necessary to protect "the best interests of children" as foreign demand for children outstripped the supply of orphans, Lu Ying, director of the China Center for Adoption Affairs, told the state-run Xinhua news agency in early 2007. The rules ensure adopters "are able to offer the Chinese children adopted the best possible environment to grow in."

Adoption agencies at the time predicted stiffer requirements would reduce the number of applications rather than slow the rate of adoptions. "The new rules will help shorten waiting time for qualified foreigners and speed up the process for children, especially the disabled, so that they can go to their new families, where they can get better education and medical treatment, more quickly," Lu told Xinhua.

That hasn't been the case. China remains the number one source of adoptive children, but by 2011 the number of Chinese children adopted by foreign families had dropped by half compared to 2007, according to the Newcastle University survey.

Blitzer now waits behind a backlog of prospective parents. "I'm grandfathered in, so I'm still eligible for a healthy infant and frankly I don't want to lose my place in line," she said. "But I'm 55 now. My kid is going to high school. What is reasonable for both of us? What is affordable?"

As China slows international adoptions, the number of children filling its orphanages is climbing -- rising to 92,000 in 2011, almost a 50% rise from 2004, according to China's Ministry of Civil Affairs.

A January protest in Russia over the government's decision to end adoptions to the United States.

 

China isn't the only nation slowing the outflow of adoptions. Russia has long been the second-largest provider of orphans for international adoption. But last December, Russia passed a bill banning adoptions to the United States by 2014. The move is widely seen as retaliation for a law the United States passed in December on human rights abusers in Russia. Emotions have run high on the issue following the death of a three-year-old Russian boy adopted in Texas earlier this year, and the 2010 incident of a seven-year-oldboy being sent back to Russia.

Other nations open, close

During her long wait for a second child from China, Blitzer has considered searching in other countries.

"Does it pay to move out of China to somewhere else? In the meantime, various countries have opened and shut down [their international adoptions]. Vietnam closed; I think Korea is iffy right now," Blitzer said. "Haiti has opened and closed since the earthquake and opened again; Russia has opened and closed. So it's a real conundrum about the right thing to do."

In May, Ghana became the latest country to suspend international adoptions, according to the U.S. State Department. It joins Bhutan, Guatemala, Kazakhstan, Kyrgyzstan, Russia and Rwanda as states that have closed their doors.

South Korea plans to phase out international adoption, and adoptions to the United States from Nepal have effectively stopped. Authorized U.S. adoption agencies left the country after the State Department warned against adopting from the Himalayan nation. The United States doesn't currently accept adoptions from Cambodia, Montenegro, and Vietnam.

Raised in America, activists lead fight to end S. Korean adoptions

Starting in July, Colombia notified it would no longer accept applications of non-Colombian parents seeking to adopt a child under six years and 11 months old, unless it's a child with special needs.

The closures are a result of concerns the children are not, in fact, orphans. Many of the top sending countries to the United States in the last 15 years, like Guatemala, Nepal and Vietnam have halted or suspended adoptions because of serious concerns about kidnapping and corruption.

"There is an inherent naivety about international adoption that it does an absolute good, but it is inherently a high-risk venture," said David Smolin, a law professor at Samford University in Alabama, who adopted a pair of children from India in 1998 only to discover that they were stolen from their mother. "To not recognize that in the face of the evidence is almost criminal."

International adoption: Saving orphans or child trafficking?

Before it closed in 2008, Guatemala sent one in every 100 children born for adoption abroad. The highest adoption rate ever recorded was South Korea in 1985, when 1.3 of every 100 children born were sent abroad for adoption, according to Selman, statistical adviser to the Hague Convention on international adoption.

Madonna with her Malawian son David Banda in 2007.

 

In an attempt to regulate adoptions, many countries ratified the Hague Adoption Convention, which aims to avoid trafficking and make it easier for children to have their citizenship finalized in their new countries. A fundamental principle of the convention is that attempts should be made to place children in their own country before international adoption is considered.

Critics say the treaty, which the U.S. joined in 2008, has restricted adoptions.

Costs -- which can be as high as $50,000 -- continue to climb. The wait can stretch for years even after an adoptive parent and child are matched as the adoption paperwork wades through the bureaucracies of both sending and receiving nations.

"I was the lead sponsor of the Hague treaty and it was my expectation that after just a few years of implementation, we would be tripling and quadrupling the number of children adopted and the opposite has happened," said Senator Mary Landrieu, a Democrat from Louisiana, in a recent documentary on international adoption. "Sometimes I've said to myself, 'why did I even help pass that treaty?'" The senator plans to introduce the "Children in Families First" legislation this week that aims to address these problems, a Landrieu staff member, who asked not be identified, told CNN.

End of the road?

UNICEF estimates that there are 151 million children who have lost at least one parent worldwide and 18 million who have lost both parents. Globally, there are more children living in foster care or institutions than there are being adopted, according to the United Nations. But most of these children are older and have special needs, and are not the healthy infants many adoptive parents typically desire.

Children with cerebral palsy at a Chinese orphanage in 2009. Beijing now gives priority to adoption of disabled children by foreign families.

 

Most nations will fast-track adoptions of older children with special needs. "Now that they're being a bit more flexible with the one-child policy, healthy Chinese babies are at a premium within China, they're not going to send those away. So what they're doing now is sending older, handicapped children who are mainly boys," Selman said.

Blitzer, the New York professor waiting to adopt a second child from China, has considered adopting a special needs child. She saw a video of a seven-year-old girl with severe leg deformities "I just fell in love with her, she had such fight," said Blitzer, who consulted an orthopedic surgeon to get advice on possible treatment before the girl was adopted by another family.

Still, as Blitzer waits for word of adopting an infant, she looks through Web pages of children awaiting adoption and wonders of the fate of kids spending their childhood in orphanages. "These kids are relegated to no option but institutionalization? That's a hard card to be dealt," Blitzer said.

CNN's Meng Meng contributed to this story