Story highlights Laerke Posselt photographed Cryos International, a sperm bank in Aarhus, Denmark

It's a big business that has sent sperm to more than 80 countries

(CNN) Cryos International is located on the fifth floor of a small building in Aarhus, Denmark. It looks like any other office, but inside, it's among the world's largest sperm banks.

Before her two-day assignment to shoot there, photographer Laerke Posselt had never been inside one. She hadn't thought much about them at all, she said.

"That's one of the amazing things about our job," Posselt said. "Suddenly, we're at a sperm bank, a place I hadn't imagined I would go."

Cryos International has sent vials of sperm to more than 80 countries, and more than 27,000 babies have been born from its donors. Donors are paid from $15 to $76 per "donation," and the vials can sell from $45 to $1,137, depending on potency and donor profiles, CNNMoney reported in October.

Photographer Laerke Posselt

It's a big business, but it still feels a little secretive, Posselt said. If people in Aarhus know it's there, they don't seem to talk about it.

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