Amazon.com Inc. has posted Q1 results showing net sales up 18% from $4.13 billion in the first quarter last year to $4.89 billion. The company said the increase would have been 25% but for unfavorable impact from exchange rate fluctuations.

Net income increased 24% to $177 million in the first quarter, compared with net income of $143 million in the first quarter of 2008.

North America sales were up 21% on the prior year quarter to $2.58 billion, while international sales - from the U.K., German, Japanese, French and Chinese sites - were $2.31 billion, up 15% from the first quarter in 2008. International growth would have been 28% if unfavorable exchange rate impact were taken into account.

Worldwide media sales, covering books, movies, music, digital downloads, software and video games, grew 7% to $2.72 billion, compared with $2.54 billion in the prior year quarter. Worldwide electronics and other general merchandise sales grew 38% to $2.05 billion, compared with $1.48 billion last year.

The Seattle-based company expects net sales to grow between 6% and 17% year-on-year in Q2, between $4.3 billion and $4.75 billion.