Premarin, the hormone medication derived from pregnant horses, is 'PREgnant MARes urINe'

Premarin was the bestselling drug in the US in 1992

The drug, derived from the urine or pregnant mares, raised ethical and animal welfare concerns, but also became wildly popular until the Women's Health Initiative study findings in 2002 (which have since been largely disproved). In the 1990s, Premarin was used to treat menopause symptoms and also to protect against osteoporosis and heart disease among older women.

Modern pregnancy tests detect a specific hormone in a woman's urine or blood.

There are multiple HRT options to treat menopause and perimenopause symptoms including hot flashes, vaginal dryness, and mood swings.

Read the 1963 study testing out an ancient Egyptian pregnancy urine test.

Mifepristone, approved in 2000, is used to end early pregnancies

The drug works by blocking progesterone, a hormone that is needed to support pregnancy. Mifepristone is typically used in combination with a second drug, misoprostol, because this regimen often causes less cramping and bleeding than just using misoprostol alone.

27% of US menopausal women used estrogen in 1999, but by 2020 that number was under 5%

The fallout of studies in the early 2000s linking hormone therapy for menopause and elevated cancer, stroke, and other health risks meant that even decades later—yet before the FDA removed its black box warning in 2025—use of HRT remained extremely uncommon. (Some users may experience a paywall.)

Menopause hormone therapy infuses the body with estrogen after the body's natural levels drop

The treatments can treat symptoms like hot flashes and vaginal dryness at varying doses. Progestogen, another hormone, is also typically prescribed with estrogen because estrogen alone can thicken the uterus lining, which elevates the risk of developing endometrial cancer.

The ancient Egyptians developed the first pregnancy test—and scientists tested it in the 1960s and discovered it was accurate about 70% of the time.

Early peptide research focused on isolating the substances from animal tissue

In the first half of the 20th century, peptides including insulin and adrenocorticotropic hormone were isolated from animals to provide life-saving medicines. ACTH was isolated from the pituitary glands of cows and pigs and insulin was isolated from the pancreas of dogs and cows.

HRT patches are popular partly because they have lower blood clotting risks than oral estradiol

Women taking estradiol for menopause or perimenopause are sometimes told oral HRT is not an option for them because it increases blood clot risks. But a large analysis in 2019 concluded that other forms of the HRT, such as the patch, creams, and gel, do not.

America doesn't have enough estradiol patches for menopause and perimenopause demand

Fueled in part by the lifting of the FDA's black box warning about HRT risks, sales of estradiol patches in the US have shot upward. More than 142 million units of the patches were sold in 2025 versus 46.5 million in 2020. Suppliers are failing to keep up with demand—11 patch products were in short supply in early 2026. (Some users may experience a paywall.)

It's never too late to start hormone replacement therapy for menopause symptoms because the products may help alleviate symptoms of menopause or fight bone loss.

Postpartum depression typically starts in the weeks following childbirth, and the disorder can keep someone from performing tasks of daily living.

Within months of a landmark 2002 study that indicated HRT harms, sales dropped by about half

In the early 2000s, Women's Health Initiative studies indicated HRT increased risk of breast cancer, heart disease, and stroke in some women—so many physicians stopped prescribing it to help with menopause symptoms. But further research has concluded that much of the elevated risk was overblown and that it was also disproportionately seen in women in their 70s who had been taking an older HRT formulation.

Common hormone therapies to treat menopausal symptoms

While there is no cure for menopause, there are ways to treat some of the intense symptoms women experience during perimenopause. There are two main hormone therapies used, one in the form of a pill, gel, or patch to treat symptoms like hot flashes, and another in the form of a cream or ring to treat symptoms like vaginal dryness. Read this article to learn more about the different hormone therapies available for menopausal women.

It's been about 30 years since a new hair loss drug was approved in the US, and women currently have no approved pills for hair loss.

FDA has removed black box warnings from hormone replacement therapy for menopause.

Horses can—and sometimes should—drink beer

Despite its reputation, beer is a good source of nutrition. In fact, it's a fairly common practice for horse owners to give beer to their horses. Beer is rich in skin-healing B vitamins, gut-stabilizing yeast, and hydration-encouraging barley. Plus, horse livers come prepared with special enzymes that break down alcohol, making inebriation nearly impossible.

In the late 1800s, New York City streets were covered with millions of pounds of horse manure thanks to a widespread horse-driven transportation industry.

BPC-157 stands for Body Protection Compound-157.

Merck developed MDMA in the early 1900s as part of its effort to create a blood clotting drug

The company's chemists were attempting to synthesize a substance that could compete with an existing patent for the best clot medicine of that time, hydrastinine. MDMA was the byproduct of that effort.

The word allergy is partly derived from the Greek word 'allos' for 'other'

For people with allergies, their immune systems recognize substances as a harmful "other"—cuing an inflammatory response. This podcast explores allergy details and related topics, including how scientists are interested in if the same allergic response mechanisms could underpin other health issues, including severe, painful symptoms around the time of menstrual cycles. Since estrogen acts on white blood cells called mast cells, which leads to the release of histamines—similar to what happens during allergic responses—an understudied question is whether the same process is fueling some of the uncomfortable symptoms around menstruation. An allergist guest notes this raises questions about if antihistamine medications like Pepsid might alleviate them, something that hasn't yet been explored in clinical trials.

Using artificial wombs to improve preterm infant health outcomes

Researchers at a hospital in the US have successfully used artificial wombs to care for preterm lambs and are now looking at the possibility of human trials. This nine-minute video includes interviews with the researchers and explains the reasoning...

Pregnancy causes a woman's blood volume to increase by up to 50%.

Scientists first observed a sperm and an egg uniting in 1876

Throughout human history, scholars and researchers have speculated on the origin of human reproduction. It wasn't until the late-19th century that the physical process of egg fertilization via sperm cells was observed (in sea urchins), forming the basis for modern fertility research.

What to know about early and premature menopause

Although it's rare, some women may experience menopause early. Early menopause describes women that are menopausal between the ages of 40 and 45. Women that go through menopause before age 40 experience premature menopause. Early experiences of menopause impact under 6% of women, and doctors can’t point to a specific reason why it happens. Learn about what we do know about the conditions here.

Only about 0.0001% of sperm, on average, successfully reach the uterine cavity

We've evolved to make pregnancy a complex and difficult process. From the initial development of the blastocyst, to the energy and nutrients needed to grow a new human, our bodies are both fighting and supporting fetal development.

HRT for menopause may not help with mental health or sleep says a large 2026 analysis

A recent analysis investigating the effects of menopause and HRT use on mental health, cognition, and brain health suggested HRT did little or nothing to aid with mental health and sleep. But the researchers caution that, among other data gaps, they didn't have information on which HRT formulations were used among their nearly 125,000 participants, so results may have varied by drug treatment.

Morphine, heroin, codeine, and more were derived from opium

Opium reached the US at about the time early colonists were itching for ways to soothe aches and pains. The active ingredient in the substance was isolated in the early 19th century, eventually leading to the manufacture and commercial sale of morphine, heroin, and other opium-based drugs.

The pharmaceutical industry evolved, in part, from the discovery of synthetic dyes

In 1856, a chemist accidentally discovered mauveine, the world's first synthetic dye, while trying to make quinine to treat malaria. The synthetic dyes that followed helped reveal germs under microscopes, paving the way for modern imaging techniques and breakthrough treatments, such as antibiotics.

Hair loss after childbirth happens because pregnancy hormones paused the normal hair shedding process during pregnancy, so the hair loss is actually your hair cycle 'catching up' with its normal process several months postpartum.

Aurea is the first US baby born following polygenic analysis

The child, born in May 2020, was selected by her parents to optimize for certain health qualities based on an analysis of her multifactorial genes by a New Jersey-based company called Genomic Prediction. Her embryo was selected for implantation based on polygenic risk scores for heart disease, diabetes, and cancer.

Scientific advances are unlocking a wide range of alternatives to IVF

From refined artificial insemination and microsurgical sperm extraction to experimental uterine transplants, scientific innovation is rapidly advancing potential fertilization technologies. But they come along with costly trials, some ethical dilemmas, regulatory issues, and more.

Scientists have not yet answered what the evolutionary benefit may be of menopause

Few animals are known to experience menopause, raising questions about why it would be evolutionarily advantageous to have women survive past their reproductive years. One leading hypothesis is the grandmother hypothesis—older women and other species known to experience menopause, like whales, can aid families and pass down knowledge to future generations.

US labs drain an estimated 500,000 horseshoe crabs of blood each year to harvest a compound that screens vaccines and medical devices for bacterial toxins.

Explore how the placenta acts as lungs, kidneys, and more in the womb.

Estrogen is a really important hormone for men, too.

See how antidepressants—used by roughly 1 in 10 Americans—were discovered.

A baby's due date is calculated from the first day of the last menstrual period—not when sexual intercourse occurred.

Read a deep dive on the 'all-purpose healing' peptide BPC-157.

The economics of horseshoe crab blood

Horseshoe crabs are older than dinosaurs and have survived five mass extinctions that wiped most life from the planet. But it's only now that their future as a species is in danger. This blood, worth about $60,000 per gallon, is hyper-sensitized to certain bacteria that are fatal to humans. This 17-minute podcast dives into humanity's pursuit of horseshoe crab blood, a "somewhat magical" mixture heavily relied on by the pharmaceutical industry.

The US FDA issued a 2025 warning about BPC-157 and other popular peptides that are marketed for various regenerative properties.

86 commonly used drugs, including certain antidepressants, painkillers, and immunosuppressants, have different results for men and women, according to recent research.

Without the option of modern blood transfusions, some doctors in the mid-1800s tried to help save cholera patients by injecting them with cow's milk, hoping it would boost their nutrition and hydration.

In the 1800s, the carcasses of the many horses that died transporting city residents were dumped in a bay in New York City.

Opium is a milky liquid substance extracted from unripe poppy plant seeds

It's been used for ages to reduce pain and induce euphoria, both of which are side effects of the plant's alkaloids—nitrogen-based compounds with pronounced physical effects. Isolating and synthesizing derivatives of these naturally occurring chemicals enabled the invention of morphine, heroin, and other opioids.

Explore a database of generic drugs to trace their origins and identify any safety concerns.

Postmenopause is a stage lasting roughly a third of a woman's life

Postmenopause is the final stage of menopause, occurring once a woman hasn't had any vaginal bleeding for a full year. She is then considered postmenopausal for the rest of her life. While some of the intense symptoms she might experience during postmenopause will decline, her risk for certain conditions and diseases will increase.

Aspirin was the first synthesized anti-inflammatory drug

Once used by the ancient Sumarians—extracted from willow bark—but now synthesized in the lab, the active ingredient of this popular medication has been used to treat headaches and pain for thousands of years.

The science and ethics of artificial wombs

Artificial wombs may be able to help preterm babies survive their early entry into the world and possibly curb the long-term adverse health effects associated with such premature birth. This article dives into the current ethics and science behind artificial wombs and ectogenesis, which is when a fetus develops in artificial conditions.