Federal Reserve

Yellen 'felt dehydrated' after long speech

Janet Yellen cuts speech short

Federal Reserve Chair Janet Yellen is said to be OK after receiving medical attention following a speech at the University of Massachusetts at Amherst on Thursday.

The U.S. central bank's head appeared to pause and cough multiple times while wrapping up her remarks on inflation and monetary policy. Yellen was offered help to leave the stage, but walked off under her own power.

Yellen was seen by the university's emergency medical staff but will continue her schedule Thursday.

"Chair Yellen felt dehydrated at the end of a long speech under bright lights. As a precaution, she was seen by EMT staff on-site at U-Mass Amherst. She felt fine afterward and has continued with her schedule Thursday evening," the Fed said in a statement.

Rate hike appropriate later this year: Yellen
Parsing Yellen's words
Analyzing the Fed Chair

She spoke for roughly an hour, stopping abruptly by saying "I think I will end here." Yellen told officials at the event that she was light-headed but recovered after sitting down and drinking water.

During the speech, Yellen said a rate hike "sometime later this year" would likely be appropriate, though the decision to abandon accommodative policy depends on economic data, Yellen said.

"Most of my colleagues and I anticipate that it will likely be appropriate to raise the target range for the federal funds rate sometime this year," Yellen said.

Read MoreFed blowing its chance to raise rates: Economist

There seemed to be little market reaction to Yellen's speech or her health.

Federal Reserve Chair Janet Yellen
Mary Schwalm | Reuters

Yellen contended that the central bank would need to tighten policy in a "timely fashion," adding that delaying could lead to abrupt moves. She reiterated the Fed's stance that the timing of the first hike matters less than making subsequent moves gradually.

"The more prudent strategy is to begin tightening in a timely fashion and at a gradual pace," Yellen said.

Her speech came a week after the Fed's policy-making committee voted to keep its short-term interest rate target near zero. Market watchers have scrutinized Yellen's words as they look for clues as to whether the U.S. central bank will hike rates after either of this year's remaining policy meetings in October and December.

In its post-meeting statement earlier this month, the policy committee said inflation has run below its target, with low energy prices contributing to the lag. It added that global economic trends could put "further downward pressure on inflation in the near-term."

On Thursday, she briefly mentioned international developments, saying "global economic and financial developments highlight the risk that a slowdown in foreign growth might restrain U.S. economic activity somewhat further."

Yellen said the inflation shortfall will likely "prove transitory." She added that low inflation can have significant costs, but it would likely move toward the Fed's 2 percent target as the economy nears full employment.

Read MoreBill Gross to the Fed: 'Get off zero, now!'

Yellen said the U.S. economy is "not far away from full employment" and touted progress in the labor market. She added that the unemployment rate would likely fall if easy policy continues.

CNBC's Steve Liesman and Alex Crippen contributed to this report.