Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of life insurance stocks MetLife (NYSE:MET), Manulife (NYSE:MFC), and ING U.S. (NYSE:VOYA) all sank more than 3% today on the Federal Reserve's decision not to cut back on its $85 billion-a-month bond purchases.

So what: The life insurance sector has soared over the past year on a steadily steepening yield curve, but the no-taper move is forcing Mr. Market to sober up a bit. After all, life insurers invest the premiums collected from customers until they have to pay them out in claims, so the Fed's decision suggests the group will be earning much lower interest for longer than Wall Street had expected.

Now what: Don't assume that tapering will just sync up over the next few months and that life insurers will follow. "We could begin later this year. But even if we do that, the subsequent steps will be dependent on continued progress in the economy," Fed Chairman Ben Bernanke said. "We don't have a fixed calendar schedule. But we do have the same basic framework that I described in June." Of course, for conservative Fools with a bit of patience, today's sector pullback might be providing an opportunity to pick up a few well-capitalized and relatively diversified insurers for the long haul.

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.