"Their cycles are starting to get shorter or longer or heavier or lighter. They're starting to experience night sweats, palpitations, or a number of vague symptoms."

Like Kassis, many women have no idea what to make of it. More alarmingly, in many cases, neither do their doctors, she says.

Doctors sometimes attribute women's symptoms to stress, weight gain, weight loss, depression, or anxiety — everything but the hormone changes that accompany perimenopause.

In fact, many symptoms linked to menopause — night sweats, palpitations, brain fog, sleep problems, mood swings — can start during perimenopause. And in most cases, a doctor with the right training can manage those symptoms with hormones or other treatments. But that often doesn't happen, says Kassis.

"Women are ignored and dismissed in a number of ways," she says. "I don't mean to suggest this treatment of patients is intentional — I truly do not believe most doctors want to intentionally gaslight their patients."

More likely, Kassis says, they simply don't have the knowledge. If an OB/GYN like Kassis didn't have the tools to recognize perimenopause in herself, where did that leave other specialists and their patients?

Even doctors who correctly diagnose perimenopausal symptoms frequently treat them incorrectly, says Steven Goldstein, MD, professor of obstetrics and gynecology at the New York University Grossman School of Medicine and past president of the The Menopause Society and the International Menopause Society.

For example, where hormone treatment is appropriate, many clinicians use a typical menopause treatment, HRT, to treat symptoms of perimenopause. That's usually a mistake, according to Goldstein.

The problem is rooted in the fundamental difference between menopause and perimenopause.

In menopause, hormone levels are consistently low. HRT works by raising overall estrogen and progesterone levels, providing stable symptom relief for many women.

That doesn't mean the pill is always the answer.

Symptoms common to perimenopause can sometimes have different causes. You and your doctor can work together to rule these out before deciding on a treatment, which can take some time and careful observation. You may need to track your symptoms for a while.

And even if you establish hormones are the issue, it can be tricky to calibrate treatment to minimize side effects and risks. Some women don't respond well to the pill during perimenopause, and others have health conditions — such as blood clots, high blood pressure, or migraine with aura — that make hormonal birth control risky.

Nor does it mean that HRT is always a bad idea in perimenopause. Especially for women who can't tolerate the pill, HRT may improve certain perimenopausal symptoms, like hot flashes, which are triggered by estrogen dips rather than spikes (though other symptoms may still worsen).

For Kassis, however, low-dose birth control was a revelation. After feeling "generally unwell" for more than a year, she felt her quality of life return to normal almost at once.

"I felt like my brain cleared and my vitality came back," Kassis says today.

It was this experience that drove her to reorient her entire practice to fill what she saw as a gaping hole in health care for women — women like Amy Thornborrow.

Amy Thornborrow had been taking low-dose birth control pills for years when she came to Kassis in 2024. She took them initially to prevent pregnancy, but also to control the debilitating migraines she used to have when she wasn't on the pill. (The relationship between hormones and migraine is complex and depends on context. Hormones may be a cause of migraine or, as in Thornborrow's case, a treatment.)

At 53, Thornborrow had likely been perimenopausal for some time, Kassis told her.

Whether she'd made the transition to full menopause was unclear because the hormonal birth control that kept her migraines at bay also likely spared her from the symptoms and misdiagnoses that plague so many women in their 40s and 50s, Kassis says.

At their first appointment, Kassis gave Thornborrow options. Hormones are perfectly safe for many perimenopausal women, Kassis told her, especially someone with Thornborrow's health history who had taken them safely for years. She could continue what she was currently using, even if she was menopausal, at least until age 55. (After age 55, doctors typically recommend a switch to HRT.)

Thornborrow could also switch to HRT, but it would require monitoring and possible medication adjustments — and it could trigger a return of her migraines.

But Thornborrow was worried about continuing to take hormones. Like many women over the last two decades, she believed that taking hormones significantly raised her risk of breast cancer — among other risks — and that the danger increased with age.

She knew some women switched from the pill to HRT, but she worried that was just more of the same.

"It was not a very developed view. I just thought, 'It's scary stuff and you don't want to do it.' And that's just distilled from whatever was coming out when my mom went through it," Thornborrow says.

Kassis hears some version of this from patients on a weekly basis. She's had to learn a balancing act: allay a patient's fears about hormones while respecting their wishes and, in many cases, the guidance of other doctors.

It's not always easy, says Goldstein. Overblown fears about estrogen have been frustratingly persistent. They originate from a 2002 decision to halt part of a huge study called the Women's Health Initiative due primarily to concerns about increased breast cancer in women who were taking estrogen (conjugated equine estrogen) and progesterone.

Though useful in some ways, the study could be misleading. The average starting age of participants — 63 — was more than 11 years past the average start of menopause and there were more smokers and women with obesity in the group compared to the regular population. Even in the small subgroup of the study that showed an increase in breast cancer, the increase was very small — less than one new case per 1,000, per year — and there was no increase in the number of women who died from the disease.

Scientists, including the WHI's principal investigators, have issued a number of retractions and reassessments in journal articles and interviews since the 2002 announcement.

But the fallout from the very public initial announcement has been hard to escape, especially the largely misunderstood link between estrogen and breast cancer.

And so today, many doctors — even gynecologists — are still wary of prescribing hormones for perimenopause or menopause, whether via low-dose birth control or HRT, doing a great disservice to women's health, according to both Goldstein and Kassis.

Part of the issue is that some doctors are simply risk averse, according to both Goldstein and Kassis. They know that patients who develop breast cancer after getting HRT have sued their health care providers, and they simply don't want the exposure.

But it's also true that many doctors, even gynecologists, simply don't have proper training in menopause and perimenopause.

"It's a real problem," says JoAnn Manson, MD, DrPH, MPH, professor of women's health at Harvard Medical School and former president of the Menopause Society.

Less than a third of OB/GYN residency programs provide specific training in menopause, and only about 1 in 10 provide residents with dedicated time at a menopause clinic. The situation is far worse for general practitioners and other specialties.

Women who can't find useful guidance should call their local health care center or state health agency and ask for a menopause specialist, Manson says. The Menopause Society website, menopause.org, may also provide specialists in your area, she says.

But it's also a good idea to dig deeper, says Goldstein.

It's not always clear what kind of training a "menopause specialist" has, Goldstein says. For many, it's nothing more than a weekend seminar. For others, it can be less, says Goldstein.

You can seek practitioners with the MSCP designation (Menopause Society Certified Practitioner). The exam is reasonably rigorous, say Goldstein and Kassis, who both have the certification, but it's no substitute for medical school training and interning under the supervision of an expert clinician.

A growing interest among women in hormone therapy (birth control or HRT) has led to an explosion of online providers to meet the demand. This type of provider may work for some women, but it's not ideal, say experts.

Short online consultations — sometimes 15 minutes or less — can't provide the kind of nuanced medical history required to treat symptoms of perimenopause or menopause safely and effectively over time, says Stephanie Faubion, MD, director of The Menopause Society and the Mayo Clinic's Center for Women's Health.

"Can they write a prescription? Yeah, they can. They can get a credit card and put a prescription on auto-renewal. But there's no consistency and continuity," says Faubion.

"Are they following their pap smears? Are they looking at their bone density? Are they making sure they got a mammogram?"

In addition, many of these companies use "compounded" versions of hormones — which can be inconsistent and are not recommended by The Menopause Society — instead of FDA-approved versions which are much more closely regulated.

In consultation with Kassis, Thornborrow has recently made the transition from birth control to HRT.

After a couple of false starts, Kassis developed a custom regimen of HRT for Thornborrow made up of transdermal estrogen and oral progesterone that keeps both her migraines and any other symptoms at bay. Thornborrow feels great.

Whether the new regimen remains successful or not, Kassis says, it will be important for them to continue to work together to monitor these changes and Thornborrow's response to the treatments.

Thornborrow worked hard to find the right doctor and in Kassis she feels she found a truly informed specialist to help guide her through this process over the long term. But she also knows that she got lucky. It was only through a chance meeting at a lecture that she got the referral to Kassis.

The tide is turning towards better training on perimenopause as medical schools take notice and doctors like Kassis work to fill in critical gaps in care. But for now, Kassis says, women entering perimenopause face a frustrating reality: they must become their own advocates in a healthcare system that often fails to recognize or properly treat their symptoms. The way to do that, she says, is to speak up, track your symptoms, ask lots of questions, and don't stop until you find a healthcare partner that truly understands your concerns.