Guillermo Arias / AP A box of seized crystal meth

When Joanne Chavarria's grandmother died last summer, she coped by turning to the bottle. "I started to drink. And then I started to smoke some weed. And then I started doing meth," says the 32-year-old from Merced, Calif. Chavarria, who began abusing drugs at the age of 12, was eight months pregnant at the time. Last August, she gave birth to drug-addicted twins, and California's Child Protective Services took the infants, as well as Chavarria's three other children, into custody.

As with other addicts, the road to recovery for Chavarria began with counseling and a drug-rehabilitation program. Less orthodox, however, was her decision to undergo a tubal ligation. "Addicts in my situation need to get their tubes tied," she says. "When you stop having kids, it makes you think about what else you can do in life." (See the best and worst moms of all time.)

Chavarria had the procedure done after meeting with Project Prevention, a North Carolinabased charity that gives drug addicts $300 if they go on long-term birth control or undergo sterilization. The aim of Barbara Harris, 57, the organization's controversial founder, is to prevent addicts from having children they can't care for and reduce the number of babies who are born exposed to drugs. "Even if their babies are fortunate enough not to have mental or physical disabilities, they're placed in the foster-care system and moved from home to home," she says. "What makes a woman's right to procreate more important than the right of a child to have a normal life?" It's an issue near and dear to Harris: she adopted four children born to the same crack-addicted woman in Los Angeles.

Established in 1997, Project Prevention has so far worked with 3,371 addicts in the U.S. Of those, 1,253 have opted for a tubal ligation or vasectomy. After getting in touch with the organization by calling its toll-free hotline (888-30-CRACK), prospective participants must mail in arrest records or official letters from social workers to confirm that they have a drug problem. Those opting for an IUD or surgical implant receive $100 when the device is inserted and $100 more six months and a year later if the device is still in use. Harris depends on donations to keep the operation going and word of mouth among addicts to find clients. But she also advertises her program by driving around the U.S. in a 30-foot motor home plastered with photos of a dead infant, a razor blade, a line of crack and a pacifier, along with the message, "Some things just don't belong together." (See "The Year in Health 2009: From A to Z.")

Harris now has her eyes on British addicts. On April 7, she flew to London to establish the U.K. wing of her charity and meet with 12 volunteers. She says she was inspired to branch out after she received 400 supportive e-mails from Brits following an appearance on a BBC Radio 4 program in February. "People said, 'You need to come to the U.K. We need this here,' " she says. "Then shortly after that I received a donation for $20,000 from a man in London. I took it as a sign we had to go." The donor, who has chosen to remain anonymous to avoid potential harassment, told Harris he donated the money because of his difficult experiences as an adopted child.

Despite the grass-roots support, the group faces widespread criticism from health professionals who work with addicts and women's advocacy groups. Simon Antrobus, chief executive of Addaction, a London-based drug and alcohol treatment agency, says Project Prevention has no place in the U.K. "Their practices are morally reprehensible and irrelevant," he says. "Sex education and contraceptive advice is part of drug-treatment work in this country. Women who use drugs can access all types of contraception for free on the National Health Service, including a number of long-term options." Other groups on both sides of the Atlantic have compared the program to Nazi-style social engineering, criticized Harris for implying that all addicts will become unfit parents and suggested that donations to the group would be better spent on drug-treatment programs. Perhaps the most common criticism, however, is that drug addicts aren't capable of making informed decisions about their reproductive future  especially when coerced with money. (See TIME's health and medicine covers.)

Harris remains committed to her hard-line approach. "If you don't think an addict is capable of making a decision, then I guess you'd agree they aren't capable of raising a child they'll conceive either," she says. And she admits that clients frequently use the $300 to secure more drugs. "They're going to do drugs with or without our money. But maybe our money means they won't rob someone tomorrow, or maybe it means they won't have to turn as many tricks the day after," she says.

That's true for some. But others use the payout to help themselves  and their families  get back on track. Chavarria spent her money buying Easter baskets and educational toys for her five children, ages 8 months to 7 years old. All of them remain in protective custody while she's in recovery. "They're always asking questions like, 'Mom, when are we coming home?' " Chavarria says. "I'm trying to keep them entertained while I'm working on me."

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