The Federal Reserve’s policy of “quantitative easing” may or may not achieve the Fed’s objective of jumpstarting a sluggish economy, but the supressed interest rates that come with the policy are sure to give pension plan sponsors more funding headaches.

That’s the prediction from investment advisory firm Mercer, which is warning sponsors of defined benefit pension plans to think carefully about how the funded status of their specific plans might be affected by the policy. Action to keep interest rates low is likely to create even further funding problems for companies that are already struggling to prop up underfunded plans, said Jonathan Barry, a partner in Mercer’s retirement, risk, and finance group.

Many companies that sponsor defined benefit pension plans are already looking for ways to minimize the effect of pension volatility in their balance sheets and income statements, according to Mercer. Even companies with frozen plans are concerned about funding; freezing a plan stops any future growth in the plans benefits, but the company still must fulfill the commitment for the benefits that have already been promised.

Now companies that are already struggling to bulk up underfunded plans may have more bad news to face as the Federal Reserve seeks to keep interest rates as low as possible. “It will continue to put a lot of pressure on pension plan liabilities,” said Barry. “Pension plan liabilities are tied to interest rates, and we’ve already seen the rates drop a lot in the past year. That raised pension liabilities quite significantly.”

Over the long term, it’s possible the Fed’s policy could help spark some recovery in equity markets, said Barry. That could help companies improve their funded status as plan assets would make equity gains in the market, but “that’s probably a year or more away,” he said.

Barry said the firm is advising plan sponsors to consider the implications and plan accordingly. “Plan sponsors have been faced with a lot of issues in the last couple of years, with forces that are beyond their control significantly affecting their pension plans,” he said. “Can you deal with the risk? If it’s not tolerable, you need to come up with a plan to mitigate it.”

Mitigating plans risk might require measures to reconsider the design of the plan, how it is funded, and how plan assets are invested, Barry said.