Global tablet shipments slowed in the second quarter from the previous three months as consumers put off purchases of Apple Inc.’s iPad to wait for a new model expected later this year, according to researcher IDC.

Unit sales declined 9.7 percent to 45.1 million, IDC said in a statement today. IPad shipments slid to 14.6 million units from 19.5 million in the first quarter, falling short of IDC’s estimate for more than 17 million, according to Tom Mainelli, research director for tablets at IDC.

Other than a new MacBook Air laptop, Apple hasn’t had a new product go on sale since last year, leaving investors and customers awaiting the release of a new iPhone and iPad, which may arrive later this year. Apple, which had previously debuted new iPads heading into the second quarter, is now holding off for the holiday shopping season, contributing to slower growth for competitors such as Samsung Electronics Co., IDC said.

“When there’s a new iPad that launches, people get more interested in tablets,” Mainelli said in an interview with Bloomberg News today. “They go out to buy one, but they don’t want a $499 tablet, so they buy one from one of the other major players.”

Steve Dowling, a spokesman at Cupertino, California-based Apple, didn’t immediately respond to a request for comment.

Apple still led the tablet market with a 32.4 percent share in the second quarter, IDC said. Samsung, in second place with 18 percent, had sales slip to 8.1 million units from 8.6 million in the first quarter, IDC said.

Growth will pick up again in the fourth quarter of this year, propelled by an updated iPad and new products expected from companies including Amazon.com Inc., IDC said.

More portable, affordable and backed by hundreds of thousands of applications, tablets are replacing personal computers as consumers’ main tool for checking e-mail, browsing websites and accessing music and movies. Tablet shipments will eclipse PCs in 2015 as consumers flock to lower-priced and smaller alternatives to the iPad, IDC predicted in May.