Urology and pelvic health company American Medical Systems Holdings Inc. said Wednesday that Japanese regulators approved marketing of its GreenLight laser system, which is designed to treat enlarged prostates.

The approval came from the Japanese Ministry of Health, Labor and Welfare. The company said about 4 million Japanese men have an enlarged prostate gland. American Medical Systems said the laser procedure has fewer side effects than surgical operations through the urethra.

The company reported its first-quarter results after the market closed on Tuesday. American Medical Systems said its profit rose 4 percent, to $21.6 million from $20.7 million. The company earned 27 cents per share in both periods as the number of shares outstanding increased in the 2011 period. Its profit totaled 33 cents per share in the latest quarter if one-time costs are excluded. Its revenue rose 4 percent, to $140.8 million from $134.9 million.

Analysts expected a profit of 31 cents per share and revenue of $137.3 million, according to FactSet.

American Medical systems said revenue from men's health products rose 5 percent to $67.4 million, and enlarged prostate therapy revenue grew 8 percent to $28.1 million. Women's health revenue grew 6 percent to $45.3 million.

A year ago, the company reported $1.8 million in revenue from its uterine health business. It sold that unit in February 2010.

In April, American Medical Systems accepted a buyout offer from Endo Pharmaceutical Holdings Inc. that was worth $2.6 billion, or $30 per share. The deal is expected to close in the third quarter.

Shares of American Medical Systems rose 27 cents to close at $29.74 on Wednesday.