Facts about sex that hold up

The body

The clitoris is an iceberg

What is visible from the outside is under a tenth of the organ. The body

The G-spot is not a spot

Decades of dissection have never found a discrete structure there. The body

The average is smaller than almost everyone guesses

15,521 men, measured by researchers rather than by themselves. The body

The hymen is not a seal, and it does not break

It is a fringe of tissue with an opening, present from birth. The animal kingdom

The male seahorse is pregnant, in the full sense

Not carrying eggs — an actual placenta, and actual labour. The animal kingdom

Bonobos use sex the way other species use diplomacy

Food arrives, tension rises, and the tension is resolved sexually. The animal kingdom

One octopus detaches an arm and sends it swimming

It swam off so convincingly that science named it as a parasite. The animal kingdom

Dolphins were the case that settled an old argument

The question of whether animals feel pleasure had an anatomical answer. History

Cornflakes were invented to suppress masturbation

The breakfast cereal was a medical intervention, and it is not a joke. History

Hysteria was a diagnosis for two thousand years

Named after the womb, and applied to almost any woman who complained. History

The condom is far older than rubber

Linen, soaked in chemicals, and tied on with a ribbon. History

Homosexuality was a mental illness until 1973

The vote that changed it was decided by evidence nobody had asked for. The research

The orgasm gap is real, and it is not about anatomy

It closes almost completely between women in same-sex relationships. The research

More sex stops helping at about once a week

Above that, the association with wellbeing flattens completely. The research

The most famous sex statistic came from a broken sample

Kinsey’s 10 per cent was never a population figure. The research

No human pheromone has ever been identified

Smell matters to attraction. That is a different claim. The myths

Nobody can tell by looking

The examination that is supposed to reveal virginity reveals nothing. The myths

Sex does not stop at sixty

The assumption that it does is why older people stop being asked. The myths

No food has ever been shown to be an aphrodisiac

Oysters, chocolate, chilli — all of it fails under a placebo control. The myths

Men do not think about sex every seven seconds

That would be 8,000 times a day. The measured figure is 19. Health

Pain during sex is common, and never something to accept

Three quarters of women experience it. Most causes are treatable. Health

Most condom failures are fit, not manufacturing

Breakage is rare. Slipping off the wrong size is not. Health

Silicone lubricant destroys silicone toys

The single most expensive thing people learn by ruining something. Health

The vagina cleans itself, and washing it causes the problem

Douching raises the risk of exactly the infection it is meant to prevent. The body

At orgasm, part of the brain switches off

Scanners found deactivation where nobody expected it. The body

Sperm counts have halved in fifty years

185 studies, 40,000 men, and a line that keeps going down. The animal kingdom

The female spotted hyena has a phallus

She urinates, mates and gives birth through the same organ. The animal kingdom

In turtles, the sand decides the sex

There are no sex chromosomes. There is a thermometer. History

Rome had a contraceptive plant, and used it up

Worth its weight in silver, and harvested into extinction. History

Pompeii’s erotic art was locked away for 180 years

Not censored by the Romans. Censored by the people who dug it up. The research

Somebody measured it with a stopwatch

500 couples, five countries, and a number far below the guess. The research

Desire often follows arousal rather than preceding it

The model everyone was taught had the sequence backwards. The myths

Shoe size predicts nothing

Two urologists measured 104 men to settle it, and it is settled. The myths

There is no reliably safe day

Sperm outlive the assumption the calendar method rests on. Health

A vaccine that prevents a cancer, with the numbers in

1.7 million women followed. The effect is not subtle. Health

The pelvic floor is a muscle, and it responds to training

The evidence is strong, and the timescale is longer than people expect. The numbers

Almost everybody fantasises, and about much the same things

4,175 people were asked in detail. The categories are few. The numbers

One in five has tried an open arrangement

Far more than swinging, and far more than most people assume. The numbers

About once a week, and falling

26,620 adults over four decades. The line goes down. The numbers

Half of women have used a vibrator, and so have many men

The first nationally representative count found it was ordinary. The numbers

Infidelity is common, and lower than everybody guesses

Around one in five married men, and one in eight married women. The numbers

A third have tried it, and the number has doubled

One of the fastest-changing figures in sex research.