For decades, millions of women steered clear of hormone replacement therapy, spooked by a black box warning linking estrogen to breast cancer. Now the FDA has wiped that warning from the books - and the rush to reclaim lost years of treatment has created a supply crisis.
The agency made the reversal official in November 2025, with the FDA commissioner holding a press conference to announce that the long-standing cancer warning was based on flawed science.
“That warning about estrogen products causing breast cancer. That’s not true, and that was never true.”
That was Dr. Gustav Lo, Chief Medical Officer at the Cosmetic Skin & Laser Center and RegenCen. He called the turnaround a watershed moment - one long overdue.
“This is a big deal in our field. This is a huge deal in our field. I wish more people knew about it,” Lo said.
The FDA’s position was clear: women had paid the price for bad data. “We feel that women have been denied the opportunity to do something that’s really, really good for their health, which is hormone replacement,” Lo said.
Demand Surges, Shelves Empty
The reversal set off a scramble. Estrogen patches - long the standard delivery method - are now in short supply across the country. Unlike a pill, the patch is a manufactured medical device with fixed production lines that can’t ramp up overnight.
“When demand started going up because of new interest, renewed interest in hormone replacement, now there’s a shortage,” Lo said.
He’s not mourning the shortage. Lo argues the patch was never the best option to begin with. “The patch is not a great device, is not a great drug delivery device,” he said, noting that the devices release most of their medication in the first 24 hours, leaving patients undertreated for the remainder of their wear cycle.
“Those patches, they release most of their medication within the first 24 hours, and then you have another 2.5 days where your levels are really below where they should be.”
The consequences are significant: Lo estimates that “about 75% of women don’t really get to therapeutic levels, so they’re not getting those health benefits like they could.” That means reduced protection against osteoporosis and cardiovascular disease - benefits many women don’t know they’re missing.
What Women Should Do Now
Lo points to two alternatives gaining traction: topical creams and gels, which allow precise, adjustable dosing, and pellets, which are inserted subcutaneously and maintain steady hormone levels for three to four months.
RegenCen’s program, called Regen HRT, takes a levels-first approach - testing patients and targeting therapeutic thresholds rather than simply waiting to see if symptoms improve.
“We have menopause-certified providers in all our clinics,” Lo said. More information is available at RegenCen.com.