(CNN)At first, it seemed like a classic celebrity romance.
Zheng Shuang, 29, was one of China's most popular actresses after shooting to fame a decade ago. Zhang Heng, 30, was a talented producer for a variety show. In 2018, the pair went public with a set of couple selfies, and often appeared affectionately in the spotlight afterward -- even co-starring in a popular reality series.
So fans were shocked when Zhang took to China's Twitter-like platform Weibo earlier this month to claim he has been stranded in the United States for more than a year, left alone to "take care of and protect two young and innocent lives."
The couple was believed to have split while two surrogate mothers they hired were pregnant with their kids, with Zheng accused of abandoning the babies.
A Chinese media outlet subsequently publicized alleged photos of the children's birth certificates, which showed they were born in December 2019 and January 2020 in the US. Zhang and Zheng were named as their parents.
It also published a recording of an alleged phone call, during which Zheng's parents allegedly suggested abandoning the children or giving them up for adoption, while Zheng allegedly expressed frustration that abortion was not a viable option given the mothers were 7 months' pregnant at the time.
The allegations shocked many in China, where family ties are typically treasured, and ignited outrage on social media. It has also sparked debate about surrogacy in a country that officially opposes the practice, yet has a booming underground market for it.
Firestorm of criticism
The scandal exploded on Weibo after Zhang's post, with the associated hashtag racking up more than 3 billions views and drawing a torrent of criticism against Zheng. And the backlash was not limited to the online sphere.
Within days, Zheng was censured by state media, and condemned by China's ruling Communist Party (CCP) agencies. "Surrogacy is clearly banned in our country, and its disregard of life makes one bristle with anger," state broadcaster CCTV said in a commentary.
The CCP's top commission overseeing political and legal affairs accused Zheng of "taking advantage of legal loopholes" by seeking surrogate mothers in the US, calling her actions "definitely not law-abiding." "Surrogacy is banned in China as it uses women's uteruses as a tool and sells life as a commercial product," the commission wrote.
Zheng was dropped by several international brands, including luxury fashion label Prada.
Responding to the firestorm, Zheng wrote on Weibo Tuesday that "this is a very sad and private matter for me." She did not directly address allegations over the surrogacy dispute, but said she "did not violate the state's instructions while on Chinese soil and respected all laws and regulations while abroad."
Technically, Zheng was right.
While surrogacy has long been in the Chinese government's crosshairs, deemed a threat to its strict population control policies, the country's national legislature has never passed legislation explicitly outlawing it.
In 2001, the Ministry of Health issued a set of regulations on assisted reproductive technology, which banned medical institutions and health care workers from "practicing any form of surrogate technology." The trade of sperm, ova, zygotes and embryos is also strictly prohibited. Medical institutions can be fined up to 30,000 yuan ($4,632) for violations, according to the rules.
But the document did not ban individuals or agencies from commissioning or providing surrogacy services, or list any according punishment. The legal limbo has led to a growing underground domestic surrogacy industry, driven by huge demand, while other Chinese couples are going abroad for surrogacy services.
The US, where commercial surrogacy is allowed for foreigners in some states, has become a top choice for the wealthy Chinese elites, thanks to its mature industry and high safety standards. A child born in the US will also come with American citizenship -- a bonus for some Chinese parents.
An outright ban?
Debates over the ethical issues of surrogacy have taken place across the globe, with opponents warning that the practice can lead to the exploitation and trafficking of women, the commodifying of the female body and children, and the deepening of inequality between rich and poor.
But the stern official condemnation of Zheng's actions comes from a government that has for decades been criticized for using forced abortion and sterilization to limit the number of children in each family. While China's one-child policy was relaxed in 2016 -- allowing couples to have two children -- the country now has a falling birth rate and a rapidly aging society, meaning it is in urgent need of more newborns to avert a looming population crisis.
The Chinese government has resorted to a flurry of policies to encourage young people to get married and have children -- to very limited success. However, it still bans the commercial use of many reproductive technologies, such as egg freezing, that would give women the freedom to have children later in life.
Surrogacy, along with other forms of reproductive assistant technology, provides an opportunity for infertile couples to have biological offspring. According to a 2009 survey from the China Population Association, 12.5% of Chinese at childbearing age -- or 40 million people -- were infertile. There are also demands for surrogacy from a large pool of older couples who lost their only child, or who simply want a second now they can, as well as a growing number of LGBT couples.