Yahoo this week pulled some anti-abortion ads that appeared in web searches for abortion clinics, following petitions from leading pro-choice groups. As CNET reports, NARAL Pro-Choice America and UltraViolet claimed that when users type "abortion clinics" into Yahoo's search field, the "majority" of displayed ads were from anti-abortion groups. They urged the web company to remove the ads, on the grounds that they were deceptive and violated Yahoo's advertising policy.

"We have found at least some of the ads to be out of compliance with our policies and we are taking them down," a Yahoo spokesperson told CNET. "We're in the process of reviewing the other ads and will take similar action if any are found to not be in compliance with our policies."

Yahoo's advertising policy specifies that displayed ads must be relevant to search results, and that any "misleading, deceptive, false or untrue" advertisements can be rejected or pulled. In their petition, NARAL and UltraViolet claimed that some of the ads deceived users with vague language or by masquerading as organizations that offer abortions.

The move comes on the heels of a similar decision from Google, which last month removed misleading web ads for crisis pregnancy centers. According to NARAL, these centers bought ads that appeared in searches for abortion clinics, even though they don't provide abortions and are known to dissuade people from pursuing them. The controversy also underscores the challenges in regulating online ads for morally sensitive search topics, as Google recently faced in Japan.