May 1 (Reuters) - New York Community Bancorp reported a loss for the first quarter on Wednesday, as the commercial real estate-focused lender set aside more funds to cover possible defaults.

The bank's exposure to rent-regulated multi-family properties and office buildings in New York has increased fears of borrowers defaulting on their loans, prompting it to set aside bigger rainy-funds.

"We also completed an in-depth due diligence of the loan portfolio, which included a thorough review of the top 250 multi-family loans, the top 50 office loans, and the top 50 non-office commercial real estate loans, and increased our credit reserve during the quarter," said newly-appointed CEO Joseph Otting in a statement.

Provision for credit losses rose to $315 million in the quarter, compared with $170 million in the year-ago period.

The bank posted a loss of $327 million, or 45 cents per share, in the three months ended March 31. That compares with a profit of $2.01 billion, or $2.87 per share, in the year-ago period. (Reporting by Niket Nishant and Manya Saini in Bengaluru; Editing by Saumyadeb Chakrabarty)