(COPENHAGEN-AFP) - A Danish travel company on Thursday claimed it could boost Denmark's dwindling birth rates by sending more couples to romantic cities like Paris, in an advertising campaign titled "Do it for Denmark!"

In a two-minute video clip featuring abandoned playgrounds and sombre-looking pensioners, Spies, the Danish unit of Britain's Thomas Cook Group, lamented that the country's birth rate was now at a 27-year low.

"At Spies we're concerned. Fewer Danes mean fewer to support the ageing population -- and tragically, fewer holidaying with us," the travel company said.

While a recent UN survey said Denmark was the happiest nation on earth, the campaign argues that it may not be the sexiest.

In the clip, a decidedly grey and depressing Scandinavia is contrasted with the City of Light, where a young Danish couple can be seen drinking in front of the Eiffel Tower, dancing in front of the Moulin Rouge and shopping for sexy underwear.

"Meet Emma. She is Danish, but even though she was born and raised in Denmark, she was made in Paris. Right up there, in that hotel room," says the advert's voiceover.

The commercial goes on to claim that Danes have 46 per cent more sex while on holiday, resulting in 10 per cent of the population being conceived then.

"We are prescribing a romantic city holiday to save Denmark's future," the group said in the tongue-in-cheek commercial.

"After all, it will also help our future business," it added.

In 2012 Denmark's birth rate was down 17 per cent since the turn of the millenium to 10.4 births per 1,000 residents, making it the lowest in the Nordic region, according to official figures

To shore it up, the company offered an "ovulation discount" to women who entered the start-date of their latest menstruation period when booking, allowing the company to calculate the best time for them to travel.

Those submitting pictures of a positive pregnancy test and a pregnancy journal after their holiday also had the chance to win gifts including a three-year supply of nappies and a family holiday.

Elderly people and gay couples were also invited to participate since "it's not just about winning, all the fun is in the participation."

On Thursday, the video clip had received 350,000 views on YouTube in less than a day.

"We have received feedback from around the world," company spokesman Torben Andersen told AFP.