PartnerRe Ltd. on Tuesday said its profits grew 9.7% to $141.5 million in the first quarter of 2009.

The Pembroke, Bermuda-based insurer and reinsurer recorded net investment losses of $70.1 million during the first quarter of 2009, compared with a $25.1 million gain in the same period last year. However, those losses were partially offset by a $57 million gain resulting from the purchase of 75% of its outstanding debt securities, the company said.

Meanwhile, PartnerRe posted a combined ratio of 87% for the quarter, compared with 92.3% in the same period last year. Contributing to that improvement was a 9.7% decrease in expenses, which fell to $815 million.

PartnerRe’s net premiums written fell 7.0% to $1.31 billion during the first quarter of 2009.

Partner Re President and Chief Executive Officer Patrick Thiele said in a statement that “the quarter was relatively uneventful in terms of large losses.”