A health insurance says it expects to eliminate about 1,200 of its 35,500 positions by March 31, 2010.

Aetna Inc., Hartford, (NYSE:AET) says it will eliminate about 625 positions this year and roughly the same number in early 2010.

“This action is consistent with our goal of aligning our cost structure with the company’s membership outlook for 2010,” Aetna says.

Aetna also plans to consolidate some field offices, but it says it “is not exiting any markets as a result of this announcement.”

The company is taking a $40 million charge in connection with the workforce reductions and real estate consolidation.

Employees who lose their jobs will get “severance benefits based on length of service” and access to outplacement programs, the company says.