At the age of 25, Judith Helfand learned she had a rare, clear cell cancer and would never be able to have children. A radical hysterectomy in 1990 took her uterus, cervix, fallopian tubes, lymph nodes and the top third of her vagina.

In 1963, while five weeks pregnant, Helfand’s mother was prescribed diethylstilbestrol (DES), a drug used to prevent miscarriage that was later proven to cause reproductive malformations and cancers in the children of mothers who took it. She had miscarried in her third pregnancy and, like an estimated 5 million other white, middle-class mothers, was convinced she was giving her baby “the best prenatal care money could buy,” Helfand said.

The consequences were devastating for mother and daughter.

“I wanted children, even though I didn’t know when that would be, to carry on the family legacy and tradition,” said Helfand, now 49. “But I really learned about the extinction of the species in a very personal way.”

“Basically, the world had shut down around me -- getting this giant cancer at that age, having to reorient my whole self,” Helfand added. “The hardest moment in my life was telling my mother that DES caused me to have cancer. I put it off as long as I could. I was terrified of the grief and guilt and my mother’s pain.”

Helfand, then a budding New York filmmaker, coped with her loss by turning her camera on herself and her family through recovery from surgery, a successful lawsuit against one of many DES-makers, and a joint journey with her mother to educate and help millions of other DES mothers and daughters.

Today, just in time for Mother’s Day, Helfand’s documentary, “A Healthy Baby Girl,” which had its world premiere in 1997 and won a Peabody Award after airing on PBS, is available digitally for the first time on iTunes through the Sundance Institute and Cinedigm.

But perhaps as importantly, Helfand's life will come full circle: Only a few hours after the announcement that her film would be re-released, Helfand received an unexpected phone call from an adoption agency that she had been working with for four years. She would finally be a mother to a healthy baby girl.

Helfand's ground-breaking film sprang from her video diary, which was shot from 1990 to 1995, and chronicles mother-daughter love, family renewal, survival, political awakening and community activism.

“The beauty of doing story over five years is you can make sure the characters evolve and our emotions evolve, and I get to a place where it’s pretty clear the cancer may have taken away my ability to have a baby biologically, but the harm was not irreparable,” she said. “It didn’t take away our spirit and the sweetness of my relationship to my mother.”

DES was first manufactured in a laboratory in 1938 and was widely given to women for five decades to prevent pregnancy problems, even though a study in 1953 had shown it was ineffective. In 1971, the U.S. Food and Drug Administration issued a bulletin advising doctors to stop prescribing the drug after research showed it caused a rare vaginal cancer in DES daughters.

An estimated 5 to 10 million women and their children were exposed to the carcinogen, according to the Centers for Disease Control and Prevention. In a national effort that followed, doctors reviewed medical records to contact those with potential problems and linked the drug to clear cell adenocarcinoma, a type of cancer that was found in children as young as 8.

“I can’t say it was just greed that made the pharmaceutical industry market DES the way they did and even obscure the information that it was a carcinogen,” Helfand said. “The complicated thing about reproduction is that the industry is playing on the deepest desires and very private fantasies and feelings based on an elemental urge every human creature has – they want to reproduce.”

Helfand got yearly screenings and was told by doctors that her chances of dodging cancer were good.

“The prevailing notion was if you didn’t get it before 21, you probably wouldn’t,” she said. “But when you are a human experiment, the data is as good and relevant as you are old. It changes as you grow up.”

As a young freelancer, Helfand had only recently bought health insurance, which “kicked in” the day of her surgery, she said. After her hysterectomy at Columbia University, Helfand moved back to her parents’ Merrick, Long Island, home to recover.

She said her mourning “seeped into everything,” as she returned to heal in the bed she slept in as a teenager.

“I didn’t want to go home alone, so the camera was my witness, my proof to my mother that this was not her fault - that we were not alone in this," she said. "It was not even unique to us – but much bigger.”

In raw footage on an 8-millimeter camera, Helfand filmed her thoughts, interviewed her parents and, as she joined DES Mothers and Daughters, an education and support group, captured the experiences of others as well.

Her film is a “love letter” to her mother, who was at first reticent to be public part of it. As she shares her daughter’s pain, Florence Helfand becomes a more vocal activist in larger fight against toxic substances, corporate greed and the use of untested “wonder drugs” on a family.

“To see the extent of my mother’s pain in the movie just scratches the surface,” said Helfand. “But she understood that filming was making me feel better.”

“A Healthy Baby Girl” launched Helfand’s filmmaking career, as she went on to make environmental justice documentaries, including a 2002 sequel, “Blue Vinyl.” She also went on to co-found Chicken & Egg Pictures, which supports women filmmakers.

Helfand began investigating adoption, but when her mother became sick with colon cancer, she moved back home to care for her. Florence Helfand died in September 2013 at the age of 84.

“My mother was still apologizing to me on her death bed,” said Helfand. “I was racing against her cancer to adopt before she died. It seemed doable.”

But her mother, who had mourned the death of her own mother while caring for her second child, knew her daughter would not be able to be a single mom to a newborn baby while grieving. So Helfand put the four-year adoption process on hold.

My mother was right,” she said. “I had planned on the film coming out on Mother’s Day and was dreading a motherless day.”

But in April, just 24 hours before Sundance announced the release of “A Healthy Baby” and as Helfand was on her way to her first family Passover Seder, the adoption agency called. She had to decide whether to take a baby girl who would be born the following morning.

Helfand said, "yes," and named her daughter Theodora Feyge Peysah Sabrina, honoring her parents, her Jewish roots and the child’s birth mother. With the child she calls “Theo” sleeping in the next room, Helfand reflected on why her film continues to be relevant.

“The DES story is just a paradigm for a much larger and very timely story about toxic chemical exposure and the impact of synthetic hormones, mimicking chemicals and carcinogens that harm the development of a healthy child and its future,” she said.

Helfand continues the fight, pushing for reform of the federal toxic chemical law and working with other activists for the long-term health of children and pregnant women. Making her up-close and personal film, “A Healthy Baby Girl,” was just the beginning of her public stance, she said.

“If you make the pain private behind closed doors, it’s not part of the public record and it’s easy to internalize it and make relationships implode and cause irreparable damage. As an artist and an activist, I refused to let that happen.”