A controversy-courting Italian ice-cream maker is in hot water for running an ad featuring a heavily pregnant nun with the strapline "immaculately conceived", after a stream of complaints to the advertising watchdog that it is offensive to Christians because it mocks the birth of Jesus.

The ad, which is featured in magazines The Lady and Grazia, features a pregnant nun enjoying a pot of Antonio Fedirici ice-cream.

The Advertising Standards Authority has launched an investigation to see if the campaign breaks the advertising code on the grounds of taste and decency. The ASA has received about 40 complaints from members of the public that it is offensive to Christians, especially Catholics, "because it mocks the virgin birth of Jesus".

Matt O'Connor, creative director at the ice-cream company, argued that it is an "intelligent, challenging and iconoclastic piece of advertising". O'Connor, who points out that he is an Irish Catholic himself, also argues that the ad "tells a deeper story", satirising the "horrific stories involving thousands of pregnant Irish women enslaved by the Catholic church in convents and who had their children taken away from them by nuns because they were seen as 'moral degenerates'".

The ad is the latest in the company's "Ice-cream is our religion" campaign.

Last year the ASA banned an ad campaign by the company featuring a a young nun and priest about to share a kiss after complaints that it was offensive to those in a religious order.

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