WASHINGTON — Christine Lagarde, the managing director of the International Monetary Fund, warned on Monday that the institution would probably cut its estimates of global growth yet again this year because of the tepid recovery in the United States, a slowdown in emerging economies and continued troubles in the euro zone.

Still, she praised the world’s central banks for taking decisive action to ease financial conditions and aid the global recovery in recent months.

“It may well be that central banks will have played and will be recognized to have played a significant role in pulling the global economy out of this great recession,” Ms. Lagarde said at a meeting at the Peterson Institute for International Economics, a Washington-based research group. “But we should not get ahead of ourselves.”

Ms. Lagarde said that the fund would most likely trim its growth estimates in a periodic update to its economic forecasts, to be delivered at a joint meeting of the World Bank and the I.M.F. in Tokyo next month. In its last estimate, made in July, the fund forecast global economic growth of 3.5 percent in 2012 and 3.9 percent in 2013. The global economy grew about 4 percent in 2011.