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FOR the first time, scientists have been able to capture the process of ovulation on video in astounding detail.

A breathtaking new clip shows a pulsing egg cell exploding out of its follicle - a sac in the ovaries that houses immature eggs before they're released for fertilisation.

A video shows the process of ovulation in real time
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A video shows the process of ovulation in real timeCredit: nature.com
Scientists used cells from mice and documented the release of an egg from the follicle
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Scientists used cells from mice and documented the release of an egg from the follicleCredit: nature.com

It shows the follicle bulging before releasing the egg in a rupture of cells and fluid.

Ovulation is the phase of the menstrual cycle when the ovary releases an egg for it to travel down the fallopian tube to be fertilised by sperm.

Despite the violent ejection of the egg from the sac, it's not usually a painful process - though some women might experience sharp twinges or a dull ache while ovulating.

The menstrual cycle is centred around this egg release process, which tends to happen midway through the 28-day cycle.

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If the egg isn't fertilised by sperm - which would result in a pregnancy - the egg is reabsorbed into the body 12 to hours later and falling hormone levels trigger the start of your period.

If the egg does come into contact with sperm, it can attach itself to the lining of the womb and develop into an embryo.

Women start developing and releasing eggs once they start their period and will probably ovulate around 400 times.

Around 15 to 30 eggs will mature in their sacs during each cycle, though only the largest and best-developed follicle ultimately releases its egg.

The follicle will swell until it ruptures at ovulation to release the egg.

This is the moment captured in astounding detail by scientists at the Max Planck Institute for Multidisciplinary Sciences, who documented the entire process of ovulation in mouse follicles in real-time.

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The team used follicles extracted from mice and then grown in petri dishes, before being encouraged to ovulate with the help of specific hormones.

The clip in question shows a mature mouse egg cell being explosively explosively expelled from its fluid-filled sac into a lab dish.

The new live imaging method developed by the team allows for the process of ovulation to be studied in unprecedented detail and could contribute to fertility research.

Researchers said the actual process of ovulation remains poorly understood as ovaries are nestled deep within the body, making them difficult to access.

On top of this, it can be hard to know when exactly ovulation will occur - it happens in a very narrow time frame and we can't predict which of the two ovaries will release an egg on any given month.

This image shows egg that has just been ovulated next to the follicle
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This image shows egg that has just been ovulated next to the follicleCredit: Christopher Thomas/Multidisciplinary Sciences

The Max Planck Institute team managed to document the entire ovulation process by extracting ovarian follicles from mice and observing them under a microscope.

Max Planck director Melina Schuh said: “We can distinguish three phases.

“The follicle expands, contracts, and finally releases the egg.”

The first phase, follicle expansion, is driven by the release of hyaluronic acid.

Under the microscope, the researchers tracked how the size and shape of the follicles changed during this phase.

Christopher Thomas, a former researcher in Dr Schuh’s department, explained: “During ovulation, fluid flows into the follicles, causing them to grow significantly."

According to the cell biologist, hyaluronic acid secretion is essential for this growth and for the success of ovulation.

When the researchers blocked the production of hyaluronic acid, the follicles expanded less and ovulation didn't occur.

Everything you need to know about ovulation

Ovulation is the release of an egg from the ovaries.

A woman is born with all her eggs and once she starts her periods, one egg develops and is released during each menstrual cycle.

Pregnancy happens if sperm meets and fertilises the egg.

Sperm can survive in the fallopian tubes for up to seven days after sex, whereas eggs only survive about 12 to 24 hours.

Occasionally, more than one egg is released during ovulation.

If more than one egg is fertilised, it can lead to a multiple pregnancy, such as twins.

Theoretically, there's only a short time when women can get pregnant, and that is the time around ovulation.

It's difficult to pinpoint exactly when ovulation happens, but in most women it happens around 10 to 16 days before their period.

Women who have a regular 28-day cycle are likely to be fertile around day 14 of their menstrual cycle, but this won't apply to women whose cycles are shorter or longer.

You can't get pregnant if ovulation doesn't occur.

Some methods of hormonal contraception – such as the combined pill, the contraceptive patch and the contraceptive injection – work by stopping ovulation.

Can you get pain during ovulation?

Some people do in fact get ovulation pain.

It often:

  • Feels like a dull pain or sharp sudden twinges
  • Lasts from a few minutes to one or two days
  • Happens about 14 days before a period
  • Only affects one side of your tummy at a time
  • Switches sides each time, depending on which ovary releases an egg

You may also have a little vaginal bleeding or discharge during ovulation.

Source: NHS

During follicle contraction, smooth muscle cells in the outer follicle layer cause the follicle to contract.

Tabea Lilian Marx, who co-authored the research, added: “When the follicle ruptures, which happens in the third phase, the egg is released and ovulation is complete.

“The surface of the follicle bulges outward and eventually ruptures, releasing the follicular fluid, the cumulus cells, and, finally, the egg."

After ovulation, the follicle forms a structure known as the corpus luteum, which produces the hormone progesterone to prepare the uterus for the implantation of an embryo.

If the egg is not fertilised or the fertilised egg doesn't implant in the womb, the corpus luteum regresses after 14 days and a new menstrual cycle begins.

Dr Schuh said: “Our findings show that ovulation is a remarkably robust process.

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"Although an external stimulus is essential to trigger ovulation, the subsequent processes operate independently of the rest of the ovary, as all the necessary information is contained within the follicle itself.

“With our new method, we and other researchers can further investigate the mechanisms of ovulation and hopefully gain new insights for human fertility research.”

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