When it comes to sex, there’s a lot of mystery — and even more misinformation.

But according to Dr. AKA - your 'friendly neighborhood OBGYn' - what actually happens inside a woman’s body during and after sex is far from random.

It’s a carefully orchestrated biological process that unfolds in four distinct, natural phases.

From racing heartbeats to powerful hormone releases, here’s the scientific explanation of what the body experiences — step by step.

The Excitement Phase: When Arousal Begins

The first stage is known as excitement — the moment arousal starts to build.

During this phase, the body shifts gears almost instantly.

Heart rate climbs, the pulse quickens, and breathing becomes deeper to increase oxygen flow throughout the body.

Beneath the skin, small blood vessels expand, which can create a soft, flushed glow.

At the same time, blood flow increases to the breasts and genitals in preparation for intimacy.

The clitoris swells and becomes highly sensitive to touch.

The vagina also swells and may appear darker in color due to the surge in circulation.

This is the body’s natural way of preparing itself physically for sexual activity.

Sex is a personal thing. Credit: eclipse_images/Getty

The Plateau Phase: Heightened Sensation and Physical Preparation

As arousal intensifies, the body enters what’s called the plateau phase.

Here, changes become even more pronounced.

The vagina begins producing natural lubrication in preparation for penetration.

Muscles across the body tighten slightly, and sensations grow stronger and more focused.

Heart rate, breathing, and blood pressure continue to rise during this stage, building toward climax.

The body remains in this heightened state until it transitions into the next phase.

The Orgasm Phase: Intense Pleasure and Hormonal Release

The third stage is orgasm — also known as climax.

This phase is marked by intense pleasure and rhythmic contractions of the pelvic muscles.

These contractions occur involuntarily and are a defining feature of orgasm.

But the changes aren’t just physical.

The brain releases powerful 'feel-good' hormones during orgasm, especially oxytocin.

Oxytocin plays a significant role in emotional bonding and feelings of closeness after sex, helping strengthen connection between partners.

It’s a neurological and physical peak that brings the body to its most heightened state.

The Resolution Phase: The Body Returns to Normal

After climax, the body moves into the resolution phase - a gradual return to baseline.

Heart rate, breathing, and blood pressure begin to decrease.

Swelling in the vagina and breasts fades, and the nipples relax.

The heightened sensitivity diminishes as circulation returns to its usual levels.

Many people report feeling calm, relaxed, sleepy, or pleasantly exhausted during this stage.

It’s the body’s natural cooldown period after intense physical and hormonal activity.

Importantly, all of these physical responses are temporary. Within minutes, the body returns to its pre-arousal state.

The Science Behind It All

What may feel spontaneous or emotional in the moment is actually a coordinated biological process.

Each of the four phases — excitement, plateau, orgasm, and resolution — plays a specific role in how the body prepares for, experiences, and recovers from sex.

From increased oxygen flow to hormone release and muscle contractions, the body follows a predictable pattern driven by natural physiology.

Understanding these stages removes the mystery and replaces it with clarity - showing that every sensation and change has a scientific explanation behind it.

Featured image credit: Oleksandr Sharkov/Getty

People have been left gobsmacked after seeing MRI images of a couple having sex.

Sexual intercourse is something most people find important in a relationship, but MRI images have let people see the act in a whole different light.

While it's a topic most people have fixated on at one stage of their lives or another, the scan images have shown exactly what goes down inside a man's and woman's bodies as they get freaky between the sheets.

Ida Sabelis and her boyfriend Jupp helped to change the understanding of the female anatomy forever after they had sexual intercourse in an MRI machine in 1991.

The couple opted to become the willing guinea pigs for their friend, Dutch scientist Menko Victor ‘Pek’ van Andel, who wanted to see what happens inside the body when a couple has sex.

Ida and Jupp's images were the first of their kind, and became the focus of a well-known British Medical Journal entry in 1999 when a more detailed study was conducted, and is still read by thousands of people every month.

While the images were captured over three decades ago, they have once again gone viral after being shared on TikTok.

The images helped scientists to discover that the vaginal canal was actually curved, after they'd initially believed it to be straight.

People were also blown away by how the images were captured, with Ida and Jupp having to get into their rhythm before stopping and holding still when instructed to by the researchers.

Ida told the publication that she'd agreed to take part in the unusual study as a "favor" to Pek, who was her best friend's partner at the time.

She was also a big campaigner for women's rights and wanted to help science broaden its understanding of the female body.

Ida and Jupp were initially supposed to have sex in a standard missionary position in the machine, but Ida - who is a professor of organizational anthropology at Amsterdam’s Vrije University - revealed that she suggested a spooning position instead, explaining: "It’s a position that for me produces hardly any arousal. Anyway, Jupp would have been too heavy in that tiny tube."

She revealed that there was plenty of laughter as the pair wriggled around inside the small tube to get into position.

Their work was groundbreaking as it had previously been a long-running belief that a woman's vagina was a straight "tunnel" and that the man's penis went in straight and came out straight, including in early depictions such as the famous Leonardo da Vinci drawing from the 1492 showing the vagina as a straight cylinder.

However, the MRI proved that "the penis has the shape of a boomerang” when inside a woman's body, bending to fit the shape of her anatomy without causing the male partner any pain.

The discovery was enormous, and led to Ida and Pek conducting a formal study between 1991 and 1999, the results of which were published in the BMJ.

These experiments recorded participants - who were all volunteers over the age of 18 who could quit at any point should they choose to - as they engaged in the missionary position.

None of the participants opted to drop out, but it was noted that it was only Ida and Jupp that were able to complete the test without the use of Viagra.

She told Vice: "It became pleasantly warm in the tube and we truly succeeded in enjoying each other in a familiar way.

"When I saw them [the images] it was just like, ‘aww that’s how we fit together’."

The article, which was published in 1999, remains one of the medical journal's "most popular articles of all time" and was even honored by BMJ on its 20th anniversary in 2019.

People were left stunned after seeing the resurfaced images, writing: "OK but like how is there space."

Others added: "They just don't do science like this anymore," and: "the most surprising thing is that they managed to get 2 ppl in an old school MRI machine... there's barely room for one person!"

Featured image credit: eclipse_images/Getty Images

A simulation video has revealed exactly what happens if someone were to swallow semen after performing oral sex.

No, we're not joking.

There seems to be a simulation for everything nowadays, thanks to technological advances, especially AI.

So now, a simulation posted to TikTok has gone viral after showing viewers exactly what happens to semen as it passes through the human body.

The video has been uploaded to the social media platform by user Dr. Boogie, which reveals how the body processes semen after it enters through the mouth.

You may think that the skinless being at the start of the video is drinking milk, but that is meant to be the depiction of semen.

The post is captioned: "When semen enters your body, this is what happens..."

Some think that swallowing semen can be an extra protein supplement. Credit: Witthaya Prasongsin / Getty

What does the simulation show?

After the figure swallows the semen, it can be seen running down their throat, with the white liquid scattered and little shapes on show, representing sperm.

According to Healthline, sperm make up approximately "one-to-five-percent of semen," while something called "seminal plasma fluid" makes up the rest of the bodily substance.

This is made up of "mostly water", as the video narrates: "When semen is swallowed, it travels down the oesophagus just like any other swallowed fluid, reaching the stomach quickly."

Once it gets to this stage, acids in the stomach, such as pepsin, work to break down proteins and deactivate the sperm cells.

So contrary to the rumors you may have heard as a teenager, you cannot get pregnant from fellatio - a relief to adolescents up and down the nation.

How long does semen stay in your body?

While a small amount may stick around a bit longer in the stomach, the majority moves quite quickly and leads to "rapid but uneventful gastric emptying."

This then enters the small intestine, where digestion goes on as normal, as more enzymes are added in, which are responsible for "absorbing any small amount of nutrients".

This is only a small amount, as a mouthful of sperm essentially contains non-significant amounts.

While a small amount "may be absorbed into the bloodstream", unfortunately, it does not give the individual any nutritional benefits, as may have been believed when you were younger.

Basically, don't swap your protein shake out just yet.

The simulation reveals that sperm is digested normally by the body. Credit: TikTok/@dr.boogie

Are there any risks?

Healthline explains that "you would likely have to consume gallons of semen to see any dietary health benefit".

They go on, explaining that "for the most part," semen is "safe" to ingest, but in "very rare circumstances," some might discover that they're allergic.

Semen doesn't take up much room in the stomach - it is soon digested and fully out of your body, eliminated as waste.

They also conclude the video by warning that you could be at risk of contracting an STI by swallowing semen, so it's important that you have an honest and open conversation with your partner.

Featured image credit: TikTok/@dr.boogie

For men, a rush of blood in the crotch area can be both a blessing and a curse, but for actors getting excited while on set would fill even the most confident of performers with embarrassment.

So, what happens when the small matter of an erection pops up while filming?

Jessica Steinrock, PhD, known on TikTok as @intimacycoordinator, recently addressed one of the frequently asked questions regarding filming intimate scenes.

When biology meets the big screen

Getting excited on set can be pretty embarrassing. Credit: Juan Moyano/Getty Images

In a video on the platform, Steinrock, who has worked as an intimacy coordinator on Yellowjackets, Netflix’s Never Have I Ever, and Hulu’s Little Fires Everywhere, explained that actors are encouraged to ask absolutely anything while on set.

She said it’s her responsibility to ensure performers have all the information they require to feel prepared and supported. That includes discussing “vascular reactions,” which she noted are a normal biological response that can happen to anyone.

For those unfamiliar with the term, a vascular reaction simply refers to increased blood flow to the genitals. Steinrock clarified that this could mean an erection, but it can also refer to increased blood flow to the vulva or natural lubrication.

How intimacy coordinators work with actors

She added that this is exactly why productions spend so much time planning barriers and modesty garments for intimate scenes.

These garments vary depending on the scene and the actors involved. For example, adhesive strapless thongs are often used for scenes showing nudity from the side or back. Actors with penises may wear padded pouches, sometimes designed with extra material to keep them securely in place. Steinrock explained that performers’ garments typically include built-in barriers to reduce physical sensation for both actors during the scene.

In some cases, additional padding, such as sponge inserts, can be added for extra coverage or comfort. Beyond maintaining modesty, these layers also ensure that if a vascular reaction does occur, it isn’t noticeable to a scene partner or the wider film crew, subsequently sparing the actor in question any awkwardness.

Steinrock concluded by emphasizing that actors can request a break at any time, without explanation. If everything is handled properly, she said, there’s no reason anyone else on set would even know an erection happened, even if the performer is particularly well-endowed.

With the film industry coming under increased scrutiny in recent times, after the revelations of sexual abuse from film mogul, Harvey Weinstein, it’s a poignant reminder of how much care and coordination now goes into filming intimate moments on screen.

Featured Image Credit: Juan Moyano/Getty

A new simulation has shed light on how female ejaculation works, offering a closer look at the anatomy involved and what the fluid actually contains.

At the center of the explanation are Skene’s glands, small structures located around the urethra in women and often described as the “female prostate.” These glands share a developmental origin with the male prostate, as both come from the same early embryonic tissue.

What does female ejaculation look like?

In the earliest stages of development, embryos, regardless of sex, have tissue that can develop into either testes or ovaries. This process depends on genetic signals, particularly the presence or absence of a Y chromosome.

If present, the tissue develops into testes and produces hormones like testosterone. Without it, the tissue becomes ovaries, leading to the development of female reproductive structures.

Credit: Flashpop / Getty

Skene’s glands are positioned on either side of the urethra, near its opening, and are relatively small, about the size of a pea. They are made up of clusters of cells that produce fluid, which drains through ducts into the urethra.

Although their exact role is still being studied, researchers believe these glands contribute to both urinary and sexual health. They may release fluid that helps lubricate the urethra, potentially reducing the risk of infection.

During sexual arousal, increased blood flow causes surrounding tissue to swell, stimulating the glands to produce mucus-like secretions that can enhance lubrication and comfort.

The release of fluid during orgasm

Some women experience a release of fluid during orgasm, known as female ejaculation. The source of this fluid is still debated, but Skene’s glands are thought to play a role.

Typically, the amount released is small, around “a teaspoon,” or roughly 3 to 5 millilitres, and is expelled through the urethra.

The fluid is described as looking “like watered down fat-free milk,” and notably, it “does not smell like urine.” Its composition is largely water, but it also contains electrolytes such as sodium, potassium, and chloride.

In addition, it includes substances like prostate-specific antigen (PSA), also found in male seminal fluid, as well as glucose, fructose, immune proteins, and mucus.

While the presence of PSA has led some to compare Skene’s glands directly to the male prostate, experts note that they are not identical in function. However, the similarities do suggest a shared biological role in reproductive and sexual physiology.

Featured Image. Credit: eclipse_images / Getty