Sen. Chuck Grassley (R-Iowa) called Friday for the Finance Committee to investigate health insurance rate increases and how they are affecting families, individuals and employers.

Grassley, who is the top Republican on the committee, noted the issue in a letter to  chairman Max Baucus (D-Mont.). He went on to ask for a special hearing to address it.

"The cost of health insurance has been an important part of the health reform debate since it began," he wrote, "and we should use all the resources available, including a public hearing, to review the current facts and inform our constituents."

Insurance carriers, blaming rising costs from March's healthcare overhaul, have recently asked authorities in some states to approve rate increases of more than 20 percent.