Losses continue at West Penn Allegheny Health System, which said Thursday it lost $34.1 million in the last three months of 2011, according to its most recent financial statement. That compared to a net loss of $1.4 million in the same quarter the year before. The troubled five-hospital health system's loss was driven by a 7.3 percent drop in revenue, to $387.3 million for the October-December quarter, compared to $417.8 million in the same quarter the year before.