WHEN Justin Bieber posted a picture of himself topless and cradling a baby last week, he wrote: “Witness the most squishy cute gumdrop ever.”

He was obviously talking about his little niece Iris, but there were plenty of women around the world who felt just as mushy looking at singer Justin, 26.

Justin Bieber made women broody when he posted a picture of himself holding his baby niece while topless
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Justin Bieber made women broody when he posted a picture of himself holding his baby niece while toplessCredit: Capital Pictures
The picture was liked more than seven million times and prompted Dwayne “The Rock” Johnson to say: “This image pretty much seals the deal. Fully expect you and H to have a baby in 2021” – as if there was no way Hailey could see this photo and not want to have a child with her husband.

In 1986, art retailer Athena famously photographed a male model holding a baby boy.

It became the biggest-selling poster in British history and model Adam Perry boasted of sleeping with 3,000 women after appearing in the shot (Not cool! – Fab Daily ed).

And it seems no-one can resist swooning when faced with a guy clutching a kid.

Celebs like Ashley Banjo often send social media into meltdown when they post topless pics with their offspring
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Celebs like Ashley Banjo often send social media into meltdown when they post topless pics with their offspringCredit: BackGrid
Earlier this month, Vicky Pattison, 31, hinted that she was broody when she gushed about her niece sitting on her boyfriend’s lap. She said: “If my future looks anything like this I will be a pretty happy bunny.”

Celebs including Ashley Banjo, Joe Wicks and John Legend frequently send social media into meltdown when they post topless pics with their offspring.

But what is it about a man clasping a newborn that makes us go so weak at the knees?

Behavioural profiler Lily Walford says: “An image of a man with a baby triggers that feeling of seeing a man that’s worth mating with.

Athena's 1986 photo of a male model holding a baby boy became the biggest-selling poster in British history
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Athena’s 1986 photo of a male model holding a baby boy became the biggest-selling poster in British historyCredit: Spencer Rowell
“We are here to survive and to successfully procreate, so seeing a guy with a baby shows us someone who has the capability to nurture and protect our offspring, which can cause those ovaries to ache.”

During ovulation, women have a spike of oestrogen and progesterone levels.

These hormonal and chemical changes within the body can cause us to experience short-term behaviours, such as an urgency to procreate.

Lily, a relationship coach, adds: “Emotional availability and vulnerability is also something that women naturally value.

Seeing an image of a man with a baby, like this snap of Joe Wicks, 'triggers that feeling of seeing a man that’s worth mating with'
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Seeing an image of a man with a baby, like this snap of Joe Wicks, ‘triggers that feeling of seeing a man that’s worth mating with’
“So when we see men with a baby, we see the nurturing side of his personality.

“When we date, we always take time to look at the future of the relationship, asking is this someone who I can have a future with?

“So when we see a man with a baby it makes it easier for us to fantasise about.”

But it’s not just the men that make our eyes pop with love hearts – babies do too.

When we see men like John Legend with a baby, we see 'the nurturing side of his personality'
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When we see men like John Legend with a baby, we see ‘the nurturing side of his personality’Credit: Instagram

“We also have a release of the chemicals dopamine and oxytocin when looking at babies,” says Lily.

Oxytocin is released in men, too, when they hold babies.

Lily says: “Women are highly empathetic and can easily recognise the bond that a man is having with that baby from just looking at them, whether that’s real life or a photo.”