Aetna Inc. CEO Mark Bertolini on Dec. 9 defended the company's decision to pull out from Affordable Care Act health insurance exchanges, saying the move was driven by increasing losses Aetna was incurring through the exchanges and was not a retaliation to government efforts to block its planned takeover of Humana Inc., Bloomberg News reported the same day.

During the trial of the lawsuit against the planned merger, Bertolini said the firm had to make a decision "to stop the bleeding" after it projected losses of $800 million to $900 million in 2017 from the insurance exchanges.

In late July, the U.S. Department of Justice filed a lawsuit to thwart the planned tie-up over concerns that the deal would lead to a loss of competition and price hikes. Within weeks, Aetna announced that it is reducing its exchange footprint in 2017 after suffering a pretax loss of $200 million from its individual products during the second quarter.

In a July 5 letter, Bertolini had told the DOJ that it would pull back from ACA exchanges in 2017 if the DOJ were to challenge its pending acquisition of Humana. In his testimony, Bertolini said the letter was a response to the government's questions, Bloomberg added.