Antiabortion politics are delaying treatments for some of the most common and debilitating conditions affecting women: endometriosis, cancer and chronic illness.
This is Part 2 of 3 in the series, “The Moral Property of Women: How Antiabortion Politics Are Withholding Medical Care,” a serialized version of the Winter 2026 print feature article. Part 1 examined how politics stalled mifepristone research for fibroids, forcing millions of women toward invasive surgery. Part 3, out Friday, explores the drug’s promise as a safer, non-hormonal form of contraception—and the political forces working to keep it tightly controlled.
The story of mifepristone and fibroids is not an isolated case—it is a pattern. Across a range of conditions that disproportionately affect women, research into the drug’s potential has been slowed, defunded or blocked altogether. Nowhere is that clearer than in the treatment of endometriosis and other serious illnesses that leave millions of women in chronic pain.
Endometriosis
Endometriosis offers a second window into what mifepristone could do. The condition occurs when endometrium cells grow outside the uterus. This can lead to chronic pelvic and back pain, heavy or abnormal bleeding, pain during sex or bowel movements, fatigue, bloating, digestive issues, infertility, anxiety and depression.
Endometriosis afflicts an estimated 10 percent of reproductive-age women. Yet patients’ options remain limited and rely heavily on surgery. Common treatments include laparoscopic surgery—cutting and removing endometrial tissue or destroying it with a laser or electric current—and hysterectomy.
Mifepristone, in contrast, blocks the progesterone causing this cellular growth and decreases the size of existing endometrial lesions, thereby relieving painful symptoms. The drug’s effectiveness extends to adenomyosis, a sister condition in which endometrial tissue exists within and grows into the uterine wall.
Yet, again, despite mifepristone’s potential to provide health-enhancing treatments, antiabortion politics have obstructed the development of the medication for these uses in the U.S.
Ovarian and Breast Cancer
In addition to treating fibroids and endometriosis, researchers have produced studies showing mifepristone is effective for treating ovarian and breast cancer. As early as 2006, research showed that mifepristone inhibited the growth of ovarian cancer cells and more recent research shows mifepristone may prevent ovarian cancer metastasis. Similar studies on breast cancer are even more promising. Dr. Rita Nanda, associate professor of medicine and director of the Breast Oncology Program at University of Chicago Medicine, is researching whether mifepristone can make chemotherapy more effective for some breast cancer patients.
“Activation of the glucocorticoid receptor … seems to, at least in breast cancer, lead to resistance to therapy,” says Nanda, who is conducting several trials testing mifepristone to antagonize this receptor. Glucocorticoids are produced in the adrenal glands and travel through the bloodstream to receptors throughout the body. “Our hypothesis [is] that if we block this receptor pathway and its downstream activation that we will enhance efficacy from chemotherapy and other targeted therapies … in a subset of triple negative breast cancers”—an aggressive type of breast cancer that is more difficult to cure because common treatments like targeting hormone therapy can be challenging.
Researchers in Argentina are also studying the use of mifepristone to treat breast cancer. Drs. Claudia Lenari and Paola Rojas at the National Scientific and Technical Research Council in Buenos Aires say their research showed that tumors in mice “regressed almost completely” with mifepristone treatment and that use of mifepristone in humans with luminal breast cancer may respond to this treatment. This makes sense since luminal breast cancer is one in which the cancer cells have receptors for the hormones progesterone and/or estrogen, which fuel their growth.
Growing evidence indicates mifepristone may even prevent breast cancer. Researchers in Europe and the U.S. have shown that mifepristone reduced breast tissue changes that make it prone to cancer development. In September 2024, scientists from Sweden, Scotland, the Netherlands, Iraq, Austria and England gathered at the University of Innsbruck in Austria to discuss “the urgent need for alternative and non-surgical options to prevent breast cancer, particularly for women in high-risk groups.”
… tumors in mice ‘regressed almost completely’ with mifepristone treatment …
Drs. Claudia Lenari and Paola Rojas
The current options for women who test positive for genes linked to breast cancer are limited to undergoing a bilateral risk-reducing mastectomy or taking drugs with significant side effects. Several studies of mifepristone, which blocks progesterone, have shown promise, but research worldwide has been slowed by substantial legal barriers and by the difficulty of obtaining the drug for research.
“The time is long overdue to give mifepristone the opportunity it deserves to be investigated as a nonsurgical option for primary prevention,” the group of scientists wrote in a recent Lancet article. “Research with mifepristone for preventing breast cancer needs to happen now if we are to expand options for reducing the risk of the most common cancer affecting women globally.”
Gulf War Illness
Interest is growing in utilizing mifepristone as a therapy for chronic inflammatory diseases, says Dr. Nancy Klimas, director of the Institute for Neuro-Immune Medicine at Nova Southeastern University in Fort Lauderdale, Fla. She has conducted research into using the drug to treat Gulf War Illness, a chronic condition affecting veterans of the Gulf War, characterized by symptoms like fatigue, muscle and joint pain, headaches, cognitive problems, insomnia and gastrointestinal issues. Research indicates Gulf War Illness may be caused by exposure to nerve gases that cause brain inflammation.
“We’re using [mifepristone] as a tool to reboot the … adrenal axis [organs that regulate the body’s response to stress] when it’s … underperforming. We’re trying to get it out of this stuck, underfunctioning space and reboot it back into a more normal state,” Klimas says.
Early results are encouraging, and she is optimistic that mifepristone could become part of a cure for this illness. She also sees potential for mifepristone to treat chronic fatigue syndrome, long COVID syndrome and potentially even multiple sclerosis—debilitating diseases that are two to four times more likely to affect women than men.
Yet the politics around mifepristone have made it difficult to obtain the drug for research, adding cost and delay.
“Scientists have been put in the difficult position of … taking into account the political environment around this drug,” Klimas says. “In my own design of studies, I’m having to use a more expensive, more difficult-to-obtain formulation of the drug because I don’t have confidence that in a study that might take two to three years to complete … I may not have this drug available … because of the political environment.” She adds that it’s also harder to even find funding for mifepristone research in this political environment.
Depression
Mifepristone has shown therapeutic benefits in several psychiatric disorders, including major depressive disorder, post-traumatic stress disorder (PTSD) and psychotic depression. Researchers hypothesize this effect is caused by mifepristone blocking the glucocorticoid stress hormones that contribute to depression.
A recent systematic review concluded that “numerous trials demonstrated the profound therapeutic effect that mifepristone can have on psychiatric disorders.” Across multiple studies, patients receiving mifepristone have shown a significant reduction in depressive and psychiatric symptoms compared with placebo, with no adverse events. Benefits were especially strong in people experiencing psychotic symptoms, which is roughly 20 percent of patients with major depression.
In one study of patients with bipolar disorder, two weeks of mifepristone treatment produced significant gains in verbal fluency and spatial working memory (remembering where things are). In another study involving psychotic major depression, eight days of 600 milligrams of mifepristone significantly reduced psychotic symptoms more than the placebo group, with no adverse side effects. This is in stark contrast to the standard anti- psychotic regimens, which often carry burdensome side effects.
Preclinical work has also suggested that mifepristone can alleviate symptoms of postpartum depression, though so far the studies have used only animal test subjects, such as mice.
Beyond mood disorders, other studies have explored mifepristone for treatment of Alzheimer’s disease and for alcoholism. One study found that mifepristone reduced alcohol craving by increasing cortisol levels.
If mifepristone threatens antiabortion politics as a treatment for disease, it poses an even greater challenge as a tool for contraception—one that could offer women more control with fewer side effects than existing options. Part 3 of “The Moral Property of Women,” out Friday, examines why a drug with decades of evidence behind it still provokes such fierce resistance—and what it would mean if women were finally allowed to decide how it is used.
