NEW YORK (CNNMoney.com) - Rising gas prices and health care costs have cut into the retirement savings efforts American households, according to a report released Thursday.

Seventy-six percent of respondents to the Fidelity Retirement Index survey said sharp rises in gas prices "impacted" their ability to save for retirement, and almost half of that group said gas prices had cut into the amount they regularly save.

Growing healthcare costs have also grown as a concern among future retirees. Survey respondents expected a 65-year old couple retiring today to pay $80,000 in out-of-pocket healthcare costs -- Fidelity estimates the cost closer to $200,000.

"We're at the point where Americans are beginning to realize that health care costs likely will be one of their major expenses in retirement, if not the largest, but haven't yet grasped the enormity of this cost," said Robert L. Reynolds, Vice Chairman and Chief Operating Officer of Fidelity.

Although American employees face significant hurdles in saving and planning adequately for their retirement, there was a slight increase in the readiness of respondents with workers on track to replace 57 percent of their income, post-retirement, up from 56 percent.

Fidelity estimates that 85 percent income replacement is a reasonable amount to ensure a comfortable retirement.

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