Data transfer problems during a switch of health insurance benefits administrators have caused problems for thousands of General Motors employees, retirees and their families since the beginning of the year.

Sharon Baldwin, a spokeswoman for GM, confirmed that an unknown number of GM workers, retirees and their dependents are still having problems getting health care bills and prescriptions paid for, more than three months after the benefits administrator was changed on Jan. 1.

"No one has lost benefits, and they still have continuity of care" while the glitches are being resolved, Baldwin said.

Formerly, GM workers and retirees were served by three different health care administrators, Baldwin said, but that was reduced to one on Jan. 1, when Fidelity Investments of Boston was brought in to manage the benefits. The accounts of 1.1 million workers, retirees and dependents were transferred from the previous administrators to Fidelity, but about 2 percent, or 22,000 accounts, didn"t transfer properly before the new system went live.

Many of the problem accounts were found through testing before the system went live Jan. 1, Baldwin said, but thousands of other accounts had problems that were initially undetected. GM and Fidelity heard about the problems when workers and retirees called to complain about difficulties they were having with their insurance benefits, she said.

Baldwin said she had no estimate of the number of workers and retirees who are still having trouble with their insurance accounts.

"We have emergency processes in place so that everybody has coverage, and we"ll do whatever they need" to be sure that medical and prescription claims are paid despite the glitches, Baldwin said. "We"re working through it as quickly as [GM and Fidelity IT workers] can."

GM moved to one benefits administrator to make it easier for workers and retirees to have one place where they could get benefits, she said. GM has about 170,000 workers across the U.S.

Vincent Loporchio, a spokesman for Fidelity, declined to comment on the matter, and a spokesman for the United Auto Workers union didn"t return calls for comment.