Lorena Ochoa of Mexico, playing her tee shot on the third hole during the final round of the 2010 Kraft Nabisco Championship, said she is retiring from golf to focus her energy on her new family. [David Cannon/Agence France-Presse]

Women's world golf No 1 Lorena Ochoa of Mexico announced Tuesday on her website that she will retire from the sport in which she has topped the world rankings for the past three years.

The 28-year-old star has said she wants to concentrate on her family and charity work. She married Andres Conesa, chief executive of Aeromexico airlines, last December and is now a stepmother of three.

"Lorena Ochoa confirms her retirement from the LPGA, as news reports in some media have said today," Ochoa's statement said.

"Reasons and more details on the matter will be given by Lorena personally in a press conference on Friday in Mexico City. Lorena will share this news of a new stage in her life with her sponsors, family members and friends."

The loss of Ochoa is a major blow to the LPGA, already struggling with fewer tournaments and lost sponsors because of economic setbacks.

The LPGA was hit in 2008 with the retirement of long-time world number one Annika Sorenstam of Sweden, but Sorenstam was 37 when she said farewell to start a family.

Ochoa, who won 27 events over the past six seasons, is scheduled to play next week at an LPGA event near Mexico City and the LPGA said Tuesday that she has not withdrawn from that tournament.

Ochoa, who has missed the cut only four times in 172 LPGA events, finished fourth earlier this month in the Kraft Nabisco Championship, this year's first women's golf major. She failed to crack the top-10 in three other 2010 starts.

Last season, Ochoa edged South Korea Jiyai Shin to claim her fourth consecutive LPGA Player of the Year award. She won three times in 2009 after collecting seven titles in 2008, eight in 2007 and six in 2006.

Ochoa won her first major title in 2007 at the Women's British Open and added another at the 2008 Kraft Nabisco.

The Guadalajara native, arguably the most likeable player in the game, has always credited her family, coach and friends as the most significant factors in influencing her career.

At the LPGA Tour's Kia Classic in March, the athletic Mexican told reporters: "What is important is that right now golf is my priority, and I'm trying to do my best.

"But I don't want to be playing and have kids at the same time, so when it's time to think about a family I will finish with my golf. I'll let you know."

Talk of Ochoa's retirement has been a hot topic since she married the chief executive of a Mexican airline in December in her home city of Guadalajara.

Sorenstam said she felt Ochoa was ready to begin the next chapter in her life after accomplishing so much in a short period of time.

"I understand completely what she is going through because I have just gone through this myself," the 39-year-old Sorenstam, wrote on her blog.

"Though I was older than Lorena, it is still hard to play and play at the level you demand of yourself when your heart and mind are somewhere else."

The LPGA said it would not make any comment regarding Ochoa until after her news conference on Friday.