UPDATE 1-Sealy posts Q2 net loss on charges

* Posts Q2 loss of 6 cents/shr

* Q2 sales fall 26 pct

* International sales fall 35 pct

* Sees market conditions remaining challenging

* Shares down about 7 pct

June 30 (Reuters) - Sealy Corp (ZZ.N), the world's largest mattress maker, posted a second-quarter net loss primarily due to the refinancing of some debt, but was also hurt by falling sales -- especially at its international segment.

Sealy and other mattress makers have been struggling with softer sales at its U.S. markets after cash-strapped shoppers cut down on their appetite for big-ticket items amid falling home values and tighter lending conditions.

But the company, whose brands include Sealy, Sealy Posturepedic, Stearns & Foster, had recently warned that domestic net sales have stabilized.

Sealy reported a 26 percent fall in overall sales to $298.5 million, with domestic sales falling 14 percent to $222.5 million and international sales falling 35 percent to $76.0 million.