* Q1 adj EPS $0.11 vs est $0.20/shr
* Q1 rev down 5 pct to $158.9 mln
April 30 (Reuters) - Natural gas and oil company Forest Oil Corp's first-quarter results missed analysts' estimates on increased cost and lower natural gas prices.
Total costs and expenses for the quarter increased to $190.7 million from $181.2 last year.
Natural gas prices have fallen 40 percent from last year to average $2.5 per million British thermal unit.
For the first quarter, Forest Oil posted a net loss of $33 million, or 29 cents per share, compared with a net loss of $3.3 million, or 3 cents per share, last year.
Excluding items, the company earned 11 cents per share.
Revenue fell 5 percent to $158.9 million.
Analysts, on average, were expecting the company to earn 20 cents per share, on revenue of $189.1 million, according to Thomson Reuters I/B/E/S.
Shares of the company, valued at $1.57 billion, closed at $13.32 on Monday on the New York Stock exchange.