Pro-abortion advocates keep waving around one UCSF study to prove the pill is safe.
That study quietly lost track of more than a quarter of the women in it.
Nobody knows what actually happened to fifteen hundred of those patients, and the math hides something ugly.
The UCSF Abortion Pill Study Tracked 6,034 Cases and Lost 1,580 Women
Researcher Ushma Upadhyay and her team at the University of California, San Francisco published "Effectiveness and Safety of Telehealth Medication Abortion in the USA" in Nature Medicine back in 2024.
The study followed 6,034 telehealth abortions handled by three virtual clinics across 20 states and Washington, D.C., between April 2021 and January 2022.
It's still doing work for the abortion industry two years later.
Telehealth.org journalist Julie Ivanova cited it on July 3, 2026, as proof that "studies have generally supported the safety of medication abortion provided through telehealth and at-home use."
The headline numbers do sound reassuring: 97.7 percent of abortions completed without intervention, 99.8 percent with no serious adverse event.
Here's the part Ivanova left out.
Researchers only had complete follow-up information for 4,454 of those 6,034 women.
They lost all contact with 1,421 patients and never learned what happened to another 159.
When Researchers Don't Know What Happened, They Just Assumed the Best
Add those two groups together and more than a quarter of the entire study simply vanished from the data.
Instead of tracking those women down, the researchers assumed their outcomes matched the women who did report back.
That's a dangerous assumption for a telehealth model, where a patient with a complication has no real relationship with the clinic that mailed her the pills.
A woman hemorrhaging at 2 a.m. doesn't call a stranger on a video screen.
She goes to her local emergency room, and unless someone connects that visit back to the original study, she simply disappears from the numbers as a success.
Here's a simple way to see how much that can distort the results.
Imagine 200 patients, 100 of whom report back and 98 of those complete their abortions without issue.
Researchers could call that a 98 percent success rate and quietly assume the other 100 patients look the same.
But if 21 of those missing patients ended up in the ER hemorrhaging or infected, and another 38 needed a procedure to finish a stalled abortion, this hypothetical group's real success rate falls to 80 percent, with an 11 percent serious complication rate.
That is not a hypothetical plucked from nowhere.
It lines up almost exactly with what large national studies out of Finland and Canada have found, and with what independent U.S. analyses keep turning up.
Undercounting Abortion Pill Complications Isn't New for Upadhyay
Upadhyay ran into this same problem a decade ago.
In a 2015 study, she found complications in 5.19 percent of chemical-abortion patients.
She classified only 0.31 percent of those as "serious."
Hemorrhages, infections, and failed abortions requiring surgical aspiration got excluded from the "serious" category because they didn't fit her narrower definition.
The new 2024 study runs the same trick with different numbers.
It reports a serious adverse-event rate of just 0.25 percent, but 2.3 percent of abortions were "not initially complete" and needed extra medication or surgery.
Nearly 1 percent involved a continuing pregnancy, and 1.3 percent of patients with known outcomes ended up in an emergency room.
Every one of those numbers is higher than the "serious" rate the study advertises.
The FDA's Own Mifepristone Safety Review Keeps Landing on the Same Number
This fight isn't staying inside academic journals.
Twenty-two Republican state attorneys general wrote to federal health officials in July 2025 demanding a fresh look at mifepristone, citing a separate large-scale study of insurance claims that found nearly 11 percent of patients suffered a serious adverse event.
HHS Secretary Robert F. Kennedy Jr. and FDA Commissioner Marty Makary answered two months later.
"This Administration will ensure that women's health is properly protected by thoroughly investigating the circumstances under which mifepristone can be safely dispensed," they wrote.
Notice that 11 percent figure.
It's almost identical to the number hidden inside UCSF's own worst-case math, a number nowhere to be found in Upadhyay's press-friendly headline stats.
A drug now routinely prescribed over a video call, with no ultrasound and no physical exam, is only as safe as the follow-up behind the studies defending it.
Right now, more than a quarter of one of the most-cited studies has no follow-up at all.
Sources:
- Randall O'Bannon, "Research Claiming Abortion Pill Is Safe for Women Has Massive Problems," LifeNews.com, September 15, 2026.
- Ushma Upadhyay et al., "Effectiveness and Safety of Telehealth Medication Abortion in the USA," Nature Medicine, 2024.
- Ethics and Public Policy Center, "The Abortion Pill Harms Women: Insurance Data Reveals One in Ten Patients Experiences a Serious Adverse Event," EPPC, May 2025.
- The Daily Caller, "RFK Jr. Launches Review of Abortion Pill Safety Risks, Adverse Effects," September 25, 2025.
- FiercePharma, "FDA Takes Close Look at Mifepristone REMS Program After Request From Republican AGs," September 2025.
