|Michelle Wie, of the U.S. waves as she finishes her first round at the US Women's Open (AP Photo)|
All four golfers fired a 2-under-par, 69s on the 6,142-meter Cherry Hills Country Club Course in Colorado.
Nicole Perrot of Chile was tied with Sweden's Liselotte Neumann, South Korea's Young A. Yang and American Natalie Gulbis after the first round, one-stroke off the lead at 1-under-par, 70.
Defending champion Meg Mallon of the United States and world number one Annika Sorenstam of Sweden were part of a group of five golfers tied at even-par 71.
Rain delays Thursday meant that the first round had to be finished Friday morning. The second round is under way and organizers are hoping to complete the tournament on time.
Sorenstam is attempting to win her third major tournament of the year as she tries to capture all four LPGA majors in one year. No golfer has ever won all four of them in a single season, known as a Grand Slam.
Some information for this report provided by AP.