This man has fathered 98 children by offering a free "sex service". Yes, you read that right.

Ed Houben is quite possibly the most fertile man in the world.

The 44-year-old Dutchman has fathered 98 children so far and says he plans to continue spreading his seed through a “free sex service” advertised on his website.

He started out as a sperm donor in 2002 at a Dutch fertility clinic but since then has reverted to sleeping with couples and singles who are unable to conceive on their own, saying the traditional method brings a “(m)uch better chance of conception”.

“What motivates me is meeting new people who turn out to be great, normal people and there’s some beautiful hope of creating a new life which will be loved and look after,” he tells the BBC.

“As (the) children grow up, they’ll develop their own relationship with me, or not, but they’ll know where they came from. For now, it’s mostly the initiative of the parents to visit me twice a year, for example.”

The mechanics of the arrangement are straightforward, he says.

They involve a brief getting-to-know-you process and, sometimes, a homestay at his council flat in the Dutch city of Maastricht.

“A married couple came over here for one week after many years of visiting clinics in the USA and the UK. They had tried everything, then they read about me, wrote (to) me and we had a very nice contact,” he says.

“Half a year later they managed to come, stayed for eight days, she and I slept together four times. After 10 years of trying they had their first pregnancy,” he says.

“Last year, they came a second time for their second child and it worked almost immediately.”

Mr Houben, who works as a tour guide by day, offers his services to both heterosexual and lesbian couples and singles alike.

He is a strong supporter of non-traditional families, describing the prioritisation of heterosexual couples in formal donor processes in the Netherlands as “an injustice”.

“I’m not saying the traditional family is a bad form, absolutely not. I’m just saying if they want to keep existing… we might have to reconsider what a qualified family is,” he says.

He also says that to avoid the risk of accidental interbreeding, he keeps an up-to-date list of his offspring on his computer.

“If, later on, one of my children meets someone who doesn’t know who his natural father is, he can consult this list,” he says, adding that he leaves it to his children’s mothers to decide how much of the conception story to disclose.

Mr Houben, who boasts an 80 per cent impregnation ‘success rate’, says he hopes to find the right woman to settle down with one day.

And when he does, here’s hoping she wants kids…

Would you ever sleep with a stranger to get pregnant?