More than 50 dissident Catholic groups from around the world wrote an open letter asking Pope Benedict XVI to lift the Church’s ban on birth control. They took a half-page ad in Italy’s largest daily newspaper, Corriere della Sera.

The letter stated that the Church’s ban on contraception has had "catastrophic effects"on the poor and weak of the whole world — especially in poor countries, where the Church was using its influence to block family-planning programs and condom distribution. According to the letter published in the Corriere, the appeal urges Benedict to reform the Vatican’s long-standing ban because it exposes millions of people to the risk of contracting HIV.

The appeal was intitiated by a Washington-based pro-choice advocacy group called Catholics for Choice and signed by organizations from countries across the Americas and Europe. The ad was published on the 40th anniversary of the 1968 controversial encyclical Humanae Vitae ("On Human Life") — the document issued by Pope Paul VI that prohibits Catholics from using artificial contraception.

The Vatican dismissed the idea that its stance on contraception contributed to the spread of AIDS. In fact, the Vatican spokesman, the Rev. Federico Lombardi, told the Associated Press and CBS news on Friday that the letter is ridiculous — saying that the ad is a form of "propaganda in favor of the use of contraceptives" and its findings are "completely unfounded."

"The spread of AIDS is totally independent of the religious denomination of populations and of the influence of religious hierarchies," Lombardi said.