How DO you tell your child they have 500 half-siblings because their father is a reckless serial sperm donor? The question haunting mothers across the world - including in Britain - after a Dutchman's web of deceit was exposed

When Julia and Ida wanted to start a family, they scoured the internet for a suitable father.

Partly because many more same-sex couples are having children, there is a global shortage of sperm donors, but they eventually found a candidate who appealed to them.

With Meijer's podgy cheeks and straggly blond mullet, it might have been fanciful for one of the sperm banks he supplied to claim, in his online profile, that he resembled Hollywood actors Brad Pitt and Chris Hemsworth, and Led Zeppelin singer Robert Plant.

In truth, Julia thought he looked more like a Viking. But she and Ida decided he was 'cute' — and when they met him in a hotel, to take delivery of his sample, he seemed reassuringly warm and sincere.

As Meijer didn't ask for a fee, they had no reason to doubt him when he said his motive for helping them was purely altruistic. They believed him, too, when he said he had helped to create just '14 or 15' other children.

With Jonathan Jacob Meijer's (pictured) podgy cheeks and straggly blond mullet, it might have been fanciful for one of the sperm banks he supplied to claim that he resembled Hollywood actors Brad Pitt and Chris Hemsworth, and Led Zeppelin singer Robert Plant

With Jonathan Jacob Meijer's (pictured) podgy cheeks and straggly blond mullet, it might have been fanciful for one of the sperm banks he supplied to claim that he resembled Hollywood actors Brad Pitt and Chris Hemsworth, and Led Zeppelin singer Robert Plant

Partly because many more same-sex couples are having children, there is a global shortage of sperm donors. File image

Partly because many more same-sex couples are having children, there is a global shortage of sperm donors. File image

Fast-forward two years and Julia and Ida, a married German couple whose names have been changed, have a beautiful son. A few days ago, however, they learned the sickening truth about the man they trusted enough to be their little boy's father.

Keen for him to know more about his biological 'daddy', they thought it was time to show him what Meijer looked like, so they googled the name to find a photograph.

Instead, they were confronted by a news item that shocked them to the core. The 'cute Viking' was unmasked as a serial sperm donor who roams the world and admits to fathering an astonishing 500 children, though those investigating his activities fear he could have created double that number.

Seemingly driven by a compulsion to procreate, the 41-year-old Dutchman has impregnated women in all corners of the globe, including many in Britain, allegedly lying to them to cover up his prolific activities elsewhere.

Barely a week passes without a distraught mother coming forward to claim Meijer duped her into believing he had only a handful of children.

Some of his 'victims' have set up a Facebook page with the sinister-sounding name Donor 102.

That is the number of babies he was found to have fathered in 2017, when Dutch health authorities first discovered he was secretly supplying sperm to almost every fertility clinic in the country, far exceeding the legal limit in the Netherlands, which permits donors to father 25 children by up to 12 different women.

Since then, however, Meijer has defiantly continued to expand his vast 'family' by registering with sperm banks such as Denmark-based Cryos International, the world's biggest provider, which supplies to more than 100 countries, Britain among them, and another big international fertility clinic in Ukraine.

The 'cute Viking' (pictured) was unmasked as a serial sperm donor who roams the world and admits to fathering an astonishing 500 children

The 'cute Viking' (pictured) was unmasked as a serial sperm donor who roams the world and admits to fathering an astonishing 500 children

He was secretly supplying sperm to almost every fertility clinic in the country, far exceeding the legal limit in the Netherlands, which permits donors to father 25 children by up to 12 different women. File image

He was secretly supplying sperm to almost every fertility clinic in the country, far exceeding the legal limit in the Netherlands, which permits donors to father 25 children by up to 12 different women. File image

He also makes private arrangements over the internet, where sperm donation is completely unregulated, as Julia and Ida have found to their emotional cost.

The Donorkind Foundation, a Dutch advocacy group representing donor-conceived children and their parents, claims that Meijer uses aliases when advertising his services on the internet, to circumvent national quotas. Meijer has denied this.

Eerily, in parts of Holland, he has fathered so many lookalike children, with curly blond hair and piercing blue eyes, that their mothers are starting to meet by chance because they use the same creche, work in the same office or live in the same neighbourhood.

Only when they see their children playing together, or compare photos of them, then discuss how they came into being, do they realise, to their horror, that they share the same father.

Inevitably, all this has awakened dystopian fears. The Netherlands is a small country and Ties van der Meer, Donorkind's chairman, envisages a scenario where, on reaching their teens, Meijer's children might frequent the same bar or club and fall for one another, unaware that they are dating their half-brother or sister.

It could lead to them unwittingly forming incestuous relationships and having inbred families, which carry an increased risk of genetic physical and psychiatric disorders, he says. The danger of this nightmare becoming reality will also pass down to future generations, where unsuspecting half-cousins could hook up.

None of this seems to trouble Meijer, whose one-man genetic explosion continues apace.

This week he is holidaying in Kenya and Tanzania, sparking fears that he could use the trip to create an East African branch of his vast 'family', as he has done in at least 15 other countries, according to a Donorkind member who uncovered the full extent of his seed-spreading crusade.

Meijer also makes private arrangements over the internet, where sperm donation is completely unregulated

Meijer also makes private arrangements over the internet, where sperm donation is completely unregulated

When he returns, however, the serial donor will finally be made to account for his reckless propagation. On April 13, he has been summoned to appear in a civil court in The Hague, as the defendant in a landmark legal action being brought jointly by Donorkind and 'Eva', one of the mothers who claim he lied to her about the number of children he had produced.

'Sick to her stomach' about the potential consequences for her son, Eva — who says she wouldn't have chosen him had she known he was a father of hundreds — will ask a judge to ban Meijer from impregnating more unsuspecting women, on penalty of a €100,000 fine. However, as there are no international regulations governing sperm donors, such an order would apply only in the Netherlands.

It would do nothing to protect parents in the United Kingdom, where Meijer long ago reached the legal maximum by supplying sperm for ten families. This was revealed when Cryos flagged his online donor profile (the one that likened him to Brad Pitt) with a red warning sign. Though the Danish sperm bank failed to respond to my questions this week, it has said it no longer uses Meijer.

At the Donor Conception Network, a London-based UK charity that supports more than 2,200 families with donor-conceived children, however, his unchecked spree is also causing concern.

In recent days, the charity has received calls from anxious British parents who used Meijer, and — like Julia and Ida — were blithely unaware until they read recent reports that their sons and daughters have hundreds of half-siblings. 'We have been contacted by a small number, who are leading the conversation', director Nina Barnsley told me. 'But we know they have been in touch with others, so a lot of British parties are likely to have been affected. This is a global story but there's a cohort in the UK.'

While some parents forgive Meijer for deceiving them because he helped them to have longed-for families, she says the majority either feel angry because he lied to them, or criticise themselves for failing to ask the right questions before accepting him as a donor.

There are no universal laws for sperm donors. Each country has its own rules, and transactions conducted over the internet are an unregulated free-for-all.

In the UK, men who donate via a licensed clinic remain anonymous, have no legal or financial obligations to the children they father, and are not named on the birth certificate.

File image of liquid nitrogen cryogenic tank used for the sperm donation process

File image of liquid nitrogen cryogenic tank used for the sperm donation process

Following a change in the law in 2005, however, at 18 years old donor children can apply for their father's name, address and date of birth, enabling them to make contact if they wish, and making it easier to find their half-siblings.

Yet as Ms Barnsley says, 'sharing a close, genetic, familial connection with 500 people and managing that psychologically' will present a daunting challenge. Being born in a climate of dishonesty and deception could cause these children further problems.

For their parents, the dilemma would be how, and when, to tell them about their huge network of half-brothers and sisters. The charity is offering them support in that regard.

'So much of this world works on trust,' she says. 'It's not good that these families have been lied to. This is not like going to Argos and buying something, then saying this is not the product as described. This is a human being who has been created. They are going to be connected with this man for ever. It all feels very irresponsible.'

She is choosing her words carefully, of course, yet Jonathan Meijer's detractors would say the word 'irresponsible' doesn't begin to describe him. So, what do we know about him and, more intriguingly, what possesses him to beget on such a biblical scale?

Curiously, he comes from a country that has produced a procession of serial sperm donors. Men such as the late Dr Jan Karbaat, who secretly used his own semen to impregnate at least 60 women at his fertility clinic.

And 'Louis', now in his early 70s, whose offspring — thought to exceed 200 — are still coming to light, 20 years after he stopped cycling or taking a train to different Dutch sperm banks in order to avoid suspicion.

(In a stark reminder of the perils that await Meijer's children, one of Louis' sons, now in his 30s, has told how he was matched with four of his half-sisters when he went on the dating app Tinder. This set of half-siblings now keep a list to which they can refer before choosing a partner.)

Unlike the solitary Louis, who attributes his compulsion to a dysfunctional childhood and an inability to form close relationships, Meijer doesn't claim to be motivated by unhappiness. On the contrary, he says he became a donor to spread the joys of his own idyllic childhood.

He was one of seven children from a traditional, churchgoing family. His father is an artist and his mother a pharmacy assistant.

I have been shown the now-deleted profile he provided for Cryos — where he deposited sperm every month for at least two years using the alias 'Ruud'.

It carried an appealing photo of him as an apple-cheeked boy with a mop of blond hair; presumably to show prospective mothers what their child might look like.

In his handwritten personal testimony, he said he had grown up in a loving family environment, and in his late 20s, when he heard about people who were unable to have children, he became determined to help them fulfil their dreams.

'Until that moment, all I did was for my own benefit,' he wrote. 'That was when I started to help others with having a family, a gift that would change lifes [sic] for the better, more love, more positivity and a positive future.

'All my friends and family are aware of my decision of becoming a donor, and a future wife will know this too. Also my own children.' (Meijer is unmarried but is thought to have raised a child with a past partner.) Ironically, he added: 'So this won't be something that I did secretly.'

He presented himself as a clean-living former Scout leader with a passion for various sports, drawing cartoons and recording videos. He claimed to speak five languages in addition to Dutch and said he had taught social sciences before 'working with cryptocurrency in a development trading company'.

Invited to describe the strong side of his character, he said he was 'creative, a thinker, outgoing, a dreamer'.

Oh yes, and 'musically talented' — a boast belied by the wailing renditions on his personal YouTube channel, where he also expounds his homespun philosophy on everything from the benefits of eating five raw eggs for breakfast to the importance of family life.

As for his flaws, he could only think of two. As 'a dreamer' he was inclined to be a perfectionist; and his 'sensitive nature' meant that he needed to spend time alone.

The mothers who say he has betrayed them portray him rather differently. 'God complex' and 'narcissist' are words I have heard repeatedly this week. Others believe that he is driven by a macho need to demonstrate his masculinity or exercise some form of control over women by making them pregnant.

Julia and her wife remain convinced Meijer is, at heart, 'a nice guy'. However, they surmise that he has a psychological aberration which makes him 'addicted' to having children.

Either that or, Julia remarks dryly, 'he wants to be in Guinness World Records. Those are the only two reasons that could explain why he wants to spread his genes.'

When they googled him and found that incriminating article, they called Meijer and confronted him with his deceit. 'We told him we were shocked and that it was really bad for our little one,' says Julia. 'He said he was ashamed and would never lie to us again.

'But then we found out, a few days ago, that he was in Africa. We are so worried he'll go to sperm banks there that we even called our embassies in Kenya and Tanzania to warn them, but we couldn't get a reply.'

She adds: 'For us, the worry is how we will deal with this. You don't just say to your child: 'Oh, great news, you've got hundreds of brothers and sisters, we'll bring them home for Christmas.'

'It has happened and we'll make the best of it. But we'll talk to Jonathan when he gets back and try to make him see this must stop.'

In the Netherlands, where privacy laws mean Meijer can be identified only by his first name, the sentiment is less forgiving.

While Eva has volunteered to front the case, dozens more are backing her, convinced legal action is the only way to force the rampant babymaker into retirement.

'The first step is to try to ban him from donating in this country, but then we want him banned internationally,' says Mark de Hek, the lawyer who will present the case.

'When you have two children from one donor in the same nursery, it's astonishing and the danger is clear. There is a significant chance of inbreeding.

'Recently Jonathan seemed to have calmed down (his sperm donations), perhaps because he was in a relationship. But now that relationship has ended and last month we learnt he was approaching new women, so we have speeded up the legal procedure to limit the damage before he can produce more children.'

In Britain, the Human Fertilisation and Embryology Authority urges anyone considering using a sperm donor to work with a licensed clinic which must adhere to the ten-family limit.

As the HFEA admits, however, even this can't entirely protect women desperate to conceive from men such as Meijer.

As UK rules don't apply to foreign sperm banks that supply many British clinics, and the number of times these banks use the same donor cannot be monitored, a spokesperson said, there was 'a chance the same man could create many more families overseas'.

Whatever happens in a Dutch court two weeks hence, it seems nothing can prevent the Viking stud plundering women's trust.

One shudders to think how many more children he will create on his self-avowed quest to spread the seeds of joy . . . or, perhaps more likely, bask in a sense of superhuman power and virility.

UK families affected by issues raised in this article may wish to contact Donor Conception Network: dcnetwork.org; 020 7278 2608; enquiries@dcnetwork.org

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