A woman looks over a resume during a job fair in New York June 11, 2012. REUTERS/Eric Thayer

NEW YORK (Reuters) - The number of planned layoffs at U.S. firms rose 13.5 percent in October on cuts in the pharmaceutical and financial sectors, a report on Wednesday showed.

Employers announced 45,730 layoffs last month, up from 40,289 in September, according to the report from consultants Challenger, Gray & Christmas, Inc.

But for the first time in five months, the October figure was lower than the year-ago tally, which came in at 47,724. For 2013 so far, employers have announced 433,114 cuts, close to the 433,725 seen in the first ten months of last year.

The pharmaceutical sector saw the most layoffs, with plans to cut 10,585 employees. Those cuts came mostly from pharmaceutical giant Merck & Co Inc (MRK.N). Last quarter the company reported lower sales of its Januvia diabetes treatment - its biggest product.

The financial sector saw the second-biggest cuts, with 8,717 layoffs announced. The sector has seen the deepest downsizing so far this year, with 57,591 cuts announced since January.

"The banking sector is cutting workforce levels as a direct result of an improving economy. Many banks, including Bank of America, which announced 4,200 job cuts in October, are slashing positions in their mortgage department as the number of troubled mortgages and foreclosures dwindles," said John A. Challenger, chief executive officer of Challenger, Gray & Christmas, in a statement.

"Furthermore, improvements in the economy are also pushing interest rates back up, which is curbing demand for refinancing."

The figures come two days ahead of the key U.S. non-farm payrolls report, which is forecast to show the economy added 125,000 jobs in October with the unemployment rate edging to 7.3 percent from its current 7.2 percent.

(Reporting by Luciana Lopez; Editing by Meredith Mazzilli)