Women’s health is understudied and, in many respects, poorly understood. Even the term “women’s health” is often used as a synonym for obstetrics and gynecology, though women’s reproductive years end in midlife and their reproductive organs make up a fraction of their bodies.

Because of limited research, many women and even many doctors don’t always know how symptoms present in common conditions (sleep apnea, for instance) or how to recognize and treat ones that disproportionately affect women (like autoimmune diseases). Myths swirl around what is safe during pregnancy and what is normal during menopause. And issues that affect millions of women, such as heart disease, are still widely viewed as male problems.

We asked doctors and researchers to share the misconceptions they were most eager to clear up.

Myth 1: Heart attack symptoms are clear and obvious

Heart disease is the No. 1 killer of women in the United States, but women frequently dismiss the possibility of a heart attack. This is perhaps unsurprising, given that both awareness campaigns and the popular understanding of symptoms have tended to center on men. Women’s experiences often differ.

Dr Basmah Safdar, an emergency physician and the director of Women’s Health Research at Yale, a research centre at Yale School of Medicine, said she didn’t ask women about chest pain in the E.R. Instead, she asks about chest discomfort, because more women say yes to that. Women also tend to have multiple symptoms, she said — discomfort, shortness of breath, nausea, fatigue — while men might have pain alone.

The causes of heart attacks in women can differ, too. Men usually experience a blockage of a major artery. Women can experience that, too, but many of them — including some young, fit women — instead have a blockage in a small vessel, a problem with the lining of an artery or a spasm of arteries, Dr. Safdar said.

Myth 2: Men’s and women’s immune systems are the same

Women’s immune systems tend to respond more strongly to viral threats, producing more inflammation, said Caroline Jefferies, the scientific director of the Center for Research in Women’s Health Science at Cedars-Sinai.

This is useful during acute illnesses, helping the body clear infections more efficiently.

But it can also lead to chronic problems. The double-edged sword is visible in Covid statistics, for example: Women are less likely to die from Covid, Dr. Safdar said, but more likely to get long Covid, which researchers have linked to persistent inflammation, among other factors.

Women also exhibit higher rates of autoimmune diseases. In conditions like lupus and Sjogren’s syndrome, “it’s like their antiviral immune system has been overactivated,” Dr. Jefferies said.

Myth 3: Missed periods are normal

Many women ignore missed periods if they don’t suspect pregnancy and don’t feel sick. That’s a mistake, said Dr. Chrisandra Shufelt, a professor of general internal medicine at the Mayo Clinic in Florida and the associate director of the Mayo Clinic’s Women’s Health Research Center.

“Our society sees thin, fit young women as healthy,” Dr. Shufelt said, but “if you’re a thin, fit woman who doesn’t have a menstrual cycle, that’s not healthy.”

An irregular or absent cycle — without an obvious cause, like some forms of birth control — can point to conditions like thyroid dysfunction, a pituitary tumor or a hormonal disorder called polycystic ovary syndrome.

It can also be caused by eating too little, exercising too much or being overly stressed. This type of menstrual dysfunction is linked to low estrogen and high cortisol, which in turn can lead to menopause-like effects such as bone loss and potentially coronary artery disease.

The condition is poorly understood, said Dr Shufelt, who is running a study on it.

Myth 4: Occasional bleeding after menopause is normal

The road to menopause can be so long, with periods disappearing and restarting, that women aren’t always sure they have reached it. That leads some postmenopausal women to assume bleeding is normal when it isn’t, said Dr. Karen Lu, the physician in chief at Moffitt Cancer Center in Florida and president of the Society of Gynecologic Oncology.

Abnormal bleeding, including after menopause, can signal endometrial cancer. This type of cancer causes symptoms in early stages, making it readily diagnosable if women know what to look for, Dr. Lu said.

Anyone unsure if bleeding is normal — especially in their 50s, since the average age of menopause in the United States is 51 — should see a doctor, she added.

Myth 5: All medications are dangerous during pregnancy

Many medications can harm fetuses, but others can be taken safely during pregnancy. And for those where evidence is inconclusive or there is a small chance of harm, it’s important to weigh those risks against the risks of not taking the drug, because untreated health conditions can also harm women and fetuses.

These are conversations to have with a medical provider. But Dr. Sindhu Srinivas, a professor of obstetrics and gynecology at the University of Pennsylvania, said she had seen patients discontinue medications for epilepsy, high blood pressure and depression without consulting anyone.

“All medicines are not bad,” said Dr. Srinivas, who is also the president of the Society for Maternal-Fetal Medicine, an organization for specialists in high-risk pregnancies. “There’s a risk-benefit balance of medications in pregnancy.”

Myth 6: Problems in pregnancy stay in pregnancy

Complications like gestational diabetes, gestational hypertension and pre-eclampsia generally resolve after pregnancy. But that doesn’t mean you can forget them.

“What happens during pregnancy has a nasty habit of showing up again later in life,” said Dr. Tala Al-Talib, the medical director of Johns Hopkins’s Green Spring Station cardiovascular clinic.

Because pregnancy stresses the body, it may reveal predispositions to problems that otherwise wouldn’t have been evident until later. Coronary artery disease, heart attacks, heart failure and strokes are more common in women who had a hypertensive disorder during pregnancy, and Type 2 diabetes is more common in women who had gestational diabetes.

Anyone who experiences such a complication should see a specialist after giving birth to manage their long-term risk, Dr Al Talib said.

Myth 7: Incontinence is uncommon

By some estimates, half or more of women have urinary incontinence at least occasionally. It can stem from menopause, childbirth or other causes.

Yet women tend to think it’s rare, said Dr. Alison Huang, a professor of medicine, urology, epidemiology and biostatistics at the University of California, San Francisco, and the director of the school’s Women’s Health Clinical Research Center.

Incontinence can be minor (a little leakage when coughing or sneezing) or more extensive (like urgency so sudden that you can’t make it to a bathroom). Many cases are treatable with lifestyle changes or simple exercises, but it can be hard for doctors to communicate that when women are embarrassed to admit that they are experiencing it.

Myth 8: Diseases and drugs have been well studied in women

In the mid-20th century, thousands of babies — mainly overseas — were born with severe birth defects because of thalidomide, a medication given for morning sickness and insomnia. Afterward, the Food and Drug Administration urged researchers to exclude women of childbearing age from early clinical trials.

Researchers weren’t encouraged to include women in those trials until the 1980s, and weren’t required to do so in federally funded trials until 1993. As a result, many diseases and treatments haven’t been studied in women, because even though attention and funding have increased, many trials done before 1993 weren’t repeated. Guidelines for when blood pressure drugs should be used have been based largely on data from men, Dr. Jefferies said. The popular image of heart attack symptoms? Pulled from men, too.

The issue pops up in unexpected ways. Doctors are realizing that women with sleep apnea may not snore or gasp for breath, Dr. Huang said, but they don’t fully know what symptoms are characteristic in women.

Myth 9: The doctor always knows best

Doctors are an essential resource, but it is also common for providers to dismiss women’s symptoms.

Women with migraines or conditions like endometriosis are often told they must live with the pain. It also takes years for many patients with chronic illnesses to be diagnosed. That’s true regardless of gender, but many chronic conditions are more common in women, and women are likelier to be told that their symptoms are psychological or nothing.

The experts advised women to advocate assertively for themselves and to seek second opinions.

“Know your body,” Dr Lu said. “Know what your normal is, and trust your instincts if something is not quite right.”

This article originally appeared in The New York Times.