Wall Street’s main indexes were subdued at open on Wednesday as investors geared up for the Federal Reserve’s interest rate decision later in the day, while shares of UnitedHealth fell after the insurer warned of higher medical costs.

The Dow Jones Industrial Average fell 167.42 points, or 0.49 percent, at the open to 34,044.70. The S&P 500 opened lower by 2.72 points, or 0.06 percent, at 4,366.29, while the Nasdaq Composite dropped 2.76 points, or 0.02 percent, to 13,570.56 at the opening bell.