The subprime lending unit of IndyMac Bancorp Inc. has raised its minimum borrowing standards and cut back on loans to borrowers who can not document income, the Pasadena-based bank said Friday.

IndyMac said that had it taken the actions at the beginning of the year they would have prevented $19 million in losses so far this year. The move comes amid rising defaults in the subprime mortgage sector.

However, the bank also said it expects continuing “high” credit losses in the second quarter, but those losses will reduce over time as new loans issued under the tighter credit standards form a larger portion of its portfolio.

IndyMac added that it plans to replace some of its lost revenue by offering new products, including no-money-down loans that require mortgage insurance.

Shares in IndyMac were off 48 cents, or 1.6 percent, to $30.55 in afternoon trading Friday on the New York Stock Exchange.