* Q1 same-store sales up 7 pct vs est. of 2.7 pct rise
* Jeweler benefits from its turnaround plan
* Shares up nearly 14 pct (Adds analyst's comments, background; Updates share price)
May 23 (Reuters) - Tiffany & Co's first-quarter results beat analysts' estimates on Wednesday, with strong sales of its high-end jewelry in the Americas and Asia-Pacific regions helping the company raise its annual sales and profit forecasts.
Tiffany's shares rose nearly 14 percent to a record high of $116.76 before the bell. The stock has gained 6.3 percent so far this year, outperforming the broader S&P 500 consumer discretionary index.
The New York-based upscale jeweler is benefiting from its turnaround plan that was put in place to stem price-conscious millennial shoppers from drifting to stores and websites of newer players such as Denmark's Pandora A/S and online jeweler Blue Nile.
The plan included selling cheaper-priced items to millennials as well as everyday home items such as paper clips, pocket diaries, mirrors and wine openers to appeal to a wider customer base.
"New product offerings resonated with consumers, and with its paper flowers collection of platinum and diamonds jewelry rolling out, Tiffany should continue to fare well," said Ken Perkins, founder of research firm Retail Metrics.
The company's sales in the Americas, its biggest market, rose 9 percent and Asia-Pacific 28 percent in the three months ended April 30.
Overall same-store rose 7 percent on a constant currency basis. Analysts on average had expected an increase of 2.7 percent.
The company also said its gross margins for the quarter rose 63 percent, compared with a 62.1 percent rise a year ago.
Tiffany now expects earnings per share of $4.50 to $4.70 for the year ending January 2019, compared with the prior forecast of $4.25 to $4.45 per share.
"Global economic growth remains solid and should continue to benefit Tiffany's high-end consumer. We expect Tiffany to post strong results throughout 2018," Perkins said.
First-quarter net sales rose 14.8 percent to $1.03 billion, topping analysts' estimates of $959.4 million, according to Thomson Reuters I/B/E/S.
Excluding one-time items, the company earned $1.14 per share, while Wall Street analysts had expected 83 cents per share.
Tiffany also announced a new $1 billion stock buyback program.
Reporting by Vibhuti Sharma in Bengaluru; Editing by Sai Sachin Ravikumar and Arun Koyyur