(CNBC) U.S. stocks traded lower on Wednesday, with health care shedding 1.5 percent, while investors eagerly awaited a speech from Federal Reserve Chair Janet Yellen.
"That's the number 1 thing markets are going to be focused on," said Matt Tuttle, chief investment officer at Tuttle Tactical Management, referring to Yellen's speech. "I don't think anyone has too much conviction ahead of that speech."
The benchmark S&P 500 traded about 0.7 percent lower in afternoon ET, with health care leading decliners. The Dow Jones industrial average fell approximately 90 points in choppy trade, with UnitedHealth Group contributing the most losses.
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