(CNN) For a year and a half, River Stark took down all the mirrors in her home.

Seeing her own reflection "was so traumatizing" for Stark, a transgender woman who hadn't yet undergone the surgical treatments she knew she needed. Some days, she couldn't leave the house. She tried taking her own life.

An Army veteran living with disability, she could not get this surgical care from her usual provider, the Department of Veterans Affairs, which does not pay for or perform gender transition-related surgeries.

"Sex work provided me the money to be able to change that," said Stark, 33. "That is the only thing that has literally saved my life."

Stark calls Wisconsin home but mostly lives out of a suitcase, maintaining a busy schedule as an escort, adult film performer, photographer and phone sex operator.

But now, her career is coming to an abrupt end after a bill passed by Congress in March.

"I wouldn't even call it a roadblock. I just call it the end of my career, essentially," she said.

Craigslist is an online classifieds site, divided by city or geographic area, through which users advertise a range of goods, services, jobs and housing.

Now awaiting the president's signature, the bill paves the way for sex trafficking survivors to hold websites accountable for "knowingly" facilitating their abuse. The legislation chips away at part of a 1996 act that gave a broad layer of immunity to online companies, such as Facebook or Twitter, from being held liable for what their users post.

"Any tool or service can be misused," Craigslist says in a statement that appears when users click on its personals link. "We can't take such risk without jeopardizing all our other services, so we are regretfully taking Craigslist personals offline."

The company did not immediately respond to a request for further comment.

Though the bill aims to crack down on sex trafficking and protect survivors, critics say it threatens the lives and livelihoods of sex workers who choose to work in the profession by encouraging websites like Craigslist to censor their content -- pushing some sex workers back out to the street and removing their tools for finding and screening clients.

Some sex workers are already losing their housing as a direct result of forums like Craigslist personals going dark, according to Christa B. Daring, board president of the Sex Workers Outreach Project. Many pay rent week-to-week and struggle to feed themselves and their children, they said.

"These are people who are living on the edge," said Daring, 31, a sex worker for the past 11 years. "Once you cut off just a little bit of income, people are then on the street."

Craigslist was the first site Stark used to transition away from the street, where she relied on her military training to make "snap judgments" to stay out of harm's way, dodge potentially dangerous clients and avoid getting arrested -- again. Even with the advantage of her military training, however, "most often, physical appearance and demeanor really don't tell you a whole lot," she said.

"The internet completely changed that."

Behind the link

"People are panicking," said Brooklyn-based Akynos, 40, who runs a cleaning business and has maintained a career in sex work since she began stripping at 17. "All these avenues that sex workers have to make their work safer (are) just disappearing."

Many sex workers run background checks on clients, communicate through online forums and check "bad date lists," which sex workers create to warn others about hostile clients. Stark also has a mandatory 24-hour waiting period before she agrees to meet clients, giving her time to check for criminal records and other warning signs. She learned ways to stay safe and grow her business from other sex workers online, some of whom keep blogs.

"These sites (are) the way that we connect. We can mentor each other. We can support each other. We can screen our clients," said Akynos.

Bolstering these concerns about sex worker safety is a recent research paper -- still under peer review -- that suggests Craigslist's "erotic" services section may be linked to a drop in the female homicide rate.

"There's always been erotic services sections in the back pages of alternative newspapers," said study author Scott Cunningham, an associate professor of economics at Baylor University in Texas. "But not every market had one. I don't think Waco had one.

"Well, we got a Craigslist erotic services," he added. "Every city that eventually got a Craigslist got an erotic services section."

But Craigslist didn't launch this section in every city at the same time. Cunningham's team found that cities where Craigslist launched the section for erotic services reduced their female homicide rate by up to 17.4% on average, compared with cities where the section hadn't launched.

However, it is not possible to say what portion of those homicide victims were sex workers, Cunningham said, nor is it possible to prove that Craigslist was directly responsible for the dip. Using different statistical approaches, his team found a broad range -- roughly 1% to 17% -- for the reduction in female homicide rates. This reduction wasn't seen for other types of homicides Cunningham analyzed.

The research gives quantitative insight into what is likely to happen in the wake of the new bill, he said.

"Then we're back in a world pre-internet," said Cunningham, who has conducted sex work research for the past decade. "At the margins, some of them go back to the street. Some of them go back to working for a pimp. Some of them, maybe they advertise on the dark web."

Limited information exists on the number of sex workers in the United States, including illegal acts of prostitution. According to the 2016 General Social Survey , 2% of women and 11.2% of men have ever paid or received money for sex after turning 18. Many definitions of sex work include a broader variety of services beyond prostitution, such as "erotic performances."

Akynos expects that black sex workers will be some of the hardest hit by the anti-trafficking legislation. She recently founded a group called the Black Sex Worker Collective to "help facilitate sex workers who may be looking to exit the business, as well as support those that are in the business."

"We're already marginalized. We're already criminalized in so many more ways than white people are, period," said Akynos, who specified that she was not talking about sex work alone.

"This is people's lives we're talking about here," she said. "How in the hell are they going to survive? What is going to happen to us as a whole?"

'No certainty'

The bill's supporters, including 97 senators who voted for the legislation, say it will give law enforcement tools in the fight against sex trafficking and enable survivors and their families to seek justice in the court system.

The bill followed a two-year Senate investigation into online sex trafficking on the classified ads site Backpage.com. The investigation, led by bill co-sponsors Sens. Rob Portman and Claire McCaskill, found that Backpage knowingly aided criminal sex trafficking of women and young girls, scrubbing terms from ads such as "Lolita," "teenage," "rape" and "amber alert" and publishing them on its site.

"They didn't remove the post because they didn't want to lose the revenue," Portman said on the Senate floor. "And you can imagine, this is a very lucrative business."

The investigation led Backpage to shut down its adult ads section. The site was seized by federal law enforcement agencies Friday, and on Monday the Justice Department announced that seven people have been indicted on 93 counts related to facilitating prostitution and money laundering.

Sen. Ron Wyden, one of only two senators to vote against the new bill, said in February that it would paradoxically "make it harder to catch bad actors and protect victims by driving this vile crime to shadowy corners of society that are harder for law enforcement to reach."

A spokeswoman for Portman, Emily Benavides, called this "nonsense."

"There are plenty of law enforcement agencies already conducting investigations into criminal acts on the dark web," she wrote in an e-mail. "The internet has revolutionized the trafficking of women and children, and federal law has not kept pace."

Roughly 6,000 sex trafficking cases were reported to the National Human Trafficking Hotline last year.

When asked about the concerns over sex worker safety, Benavides said, "Tell that to the mothers and fathers of daughters who've been murdered after being trafficked on Backpage."

Despite wide congressional support, a number of tech groups have voiced concerns about the legislation, alleging that its broad reach could lead to unintended negative consequences for free speech on the internet and for smaller companies whose resources don't rival those of tech giants such as Facebook and Twitter.

The American Civil Liberties Union is considering a challenge to the bill once it gets signed into law but has no definite plans to do so, said Ian Thompson, a legislative representative for the organization.

Thompson said some of the bill's language is "so broad that it's open to interpretation of what exactly is intended to be included and what's not intended to be included." Therefore, websites are pre-emptively removing "harm-reduction and anti-violence tactics that sex workers depend on for their very lives."

Just before the bill passed, McCaskill told reporters that it was "a very, very narrowly written law." Portman's representative, Benavides, echoed these sentiments to CNN, saying that "only a website that is knowingly facilitating trafficking should be worried about this bill."

Follow CNN Health on Facebook and Twitter See the latest news and share your comments with CNN Health on Facebook and Twitter.

"If there are fewer opportunities for traffickers to sell women and children online as a result of (the bill), then that's a good thing," Benavides said.

For many sex workers, however, "there is absolutely no certainty in anything that's going on right now," Stark said. "Things are literally changing day by day."