The average age of potty training has roughly doubled since the 1940s, a shift worth billions to the diaper industry.

That year, about 40% of the babies were born to unmarried parents, and about 32% of the births were born via cesarean. On average, mothers were 27.5 years old when they had their first child.

Almost all children likely used to contract poliovirus, but scientists suggest that when infants encountered it very early in life—due to poorer conditions and hygiene—they still had some maternal protection from pregnancy or through breastmilk, so the symptoms were more flu-like.

These markers of typical hearing development among infants and toddlers include turning head to sound sources within the first five months of life, babbling by about 11 months, and trying to imitate simple words by 17 months of age.

Around the world, there has been a spike in children—especially girls—experiencing early puberty and doctors are seeking to understand why. The rise has been particularly strong post-2020. Early-maturing girls are at a higher risk for developing...

Humans have over twice as long childhoods than other animals with similar lifespans like whales and elephants. A human child can grow for nearly 20 years before they become a reproducing adult. Researchers believe there's a connection between long childhoods and human's unusually large brain size, though the science is not totally clear. Dive into what scientists know here.

Newborns don't develop circadian rhythm until they are a few months old, which helps to explain their erratic sleep schedules. When they're around three months old they begin to release melatonin, which influences sleep, and around the same time they develop more regular sleeping routines.

Mother Jones magazine coined the term in an essay called "Primal Screen" about children's television habits. Writer David Engelhardt wrote that they were watching “screens within screens within screens,” and that even babies were averaging an “hour and a half of screen time a day...the typical older child, about four hours."

Sleep training, which can range from implementing a nighttime routine to letting your baby cry it out, is controversial, but does it work? While dozens of studies have found sleep interventions to be effective, it appears that many of these studies...

One of the great achievements of modern humanity has been the sea change in child mortality rates—the chance that a newborn eventually lives past puberty. For thousands of years, children had a 50% chance of not entering adulthood. About 300 years...

When it comes to how much sleep you need, age matters—and, for your health, it's important to be well rested. Young children between the ages of one and three need the most sleep: It’s recommended that toddlers get between 11 and 14 hours of...

Pregnancies involving three kids or more have dropped 62% from 1998 to 2023, a trend that the Centers for Disease Control and Prevention links to fewer embryo transfers during assisted reproduction procedures—a transition prompted by more refined techniques and technical advances. Though multiple births can occur naturally, often pregnancies involving multiple births have been the result of efforts to ensure pregnancy success by transferring multiple embryos.

A new study found that 3-year-olds were less averse to the smell of vegetables they had been repeatedly exposed to in utero, suggesting that what mothers eat in late pregnancy can leave a lasting imprint on their children's tastes.

That figure comes from an analysis published by the US Centers for Disease Control and Prevention based on data gathered on eight-year-olds in 2022. Its figures mark a significant increase from 2000, when the estimated autism figure was one in 150, but improvements in diagnosis and changes to the disease criteria that broadened the diagnostic criteria are widely believed to be driving that increase.

In July 2025, a decade after British lawmakers signed off on allowing three-parent IVF, scientists announced that eight healthy babies had already been born using this approach. The news was included in a pair of research articles published in a peer-reviewed journal that noted the oldest kids were already more than two years old, and that they were hitting developmental milestones as expected.

In the US alone, the percentage of the population meeting the clinical standard of obesity rose from less than 20% to more than 40% over the past three decades. This rise has been matched by many countries across the globe, from industrialized to developing nations.

After the "Barbie" movie premiered, the number of investors in Barbie parent company Mattel's stock grew more than six times larger on the investment platform Public, according to the platform's recent report. Other cultural trends have affected which stocks investors choose as well.

He then bought his first property at 14 years old. From studying under the “father of value investing” to revitalizing a textile company into the largest holding company in the world, Buffett’s career is one of great financial success.

While birthing twins has been a rare occurrence for humans, research suggests that twins were actually the norm much further back in primate evolution. It’s proposed that single-childbearing turned out to be critical for the evolution of larger babies with larger heads. Discover more about the shift that gives insight into primate evolution.

Companies produced items like waterproof radios and targeted them at people under 30, marketing the devices as hip ways to stay clean.

While bidets are a typical household essential in Europe, Asia, and South America, they remain uncommon in the US. Associations with infertility, the aristocracy, and brothels helped fuel their unpopularity in the states.

Throughout our lives our internal biological clocks shift. Early-to-rise toddlers become hard-to-wake teens and eventually early-to-sleep seniors. Circadian rhythm fluctuations throughout our life cycle explain some of these changes.

Kids are hardwired to prefer sweets over greens, with sweetness a shorthand for calorie-rich and bitter flavor warning of potentially noxious plants. This holds true even in the womb, where fetuses have been seen via ultrasound scans grimacing as their hosts consume kale capsules. As they age into double digits and beyond, their taste cells and sense of smell diminish, leading to broader and less sensitive palates.

Nine of the top 10 most common birthdays fall in September, with Sept. 9 being the most common. However, August is the most common birth month, followed by July and December. On the flip side, the least common birthdays are around major holidays, with Christmas Day being the rarest—probably due to doctors scheduling fewer inductions and C-sections on those days. Find out more birthday surprises here.

Between 60% and 80% of kids with allergies to milk or eggs outgrow them by age 16. The immune system doesn’t always recognize and respond to baked forms of these allergens, so when kids eat muffins and other cooked food products, their immune system may become more habituated to them and overcome food sensitivities. Aging out of other allergies is less common.

Chocolate Advent calendars began in 1958, when German companies first paired the traditional countdown with small pieces of chocolate behind each door. The idea spread slowly at first, but eventually became one of the most popular Advent calendar formats worldwide.

Here’s a snapshot of what motherhood looks like in the U.S. today, drawn from government data and Pew Research Center surveys. The list includes seven headline statistics with visual graphs, including the average age of a mother's first childbirth...

With recent advances in medicine, sanitation, and nutrition, expected lifespans have rapidly risen around the globe—resulting in a rapidly aging global population. The worldwide distribution has seen a nearly 600% jump in the population of people aged 65 and older.

Industrialization transformed childhood—from free-range, mixed-age play long embedded in human culture to the regimented, adult-controlled environments of today's schools.

Chromosomal irregularities are more likely at older maternal ages so genetic testing for a fetus of mothers-to-be at age 35 and older is often recommended. Conditions that can be screened for in utero include cystic fibrosis, Tay-Sachs disease, sickle cell disease, Down syndrome, spina bifida, Duchenne muscular dystrophy, and more.

The inventor of the at-home pregnancy test, Margaret Crane, largely hasn't taken credit for her invention until recently.

From a young age, we are primed to choose a favorite color, but strangely as we grow up, our preference often changes—and it’s largely due to influences outside our control.