Wikstrom, who had six birdies and three bogeys in heavy rain at the Kingston Heath course, was confined to indoor practice in Finland before the tournament.

"I haven't played outside for a month until I came here," Wikstrom said. "On a couple of holes we got pretty hard rain. It's OK, I come from Scandinavia."

The rain eased in the afternoon, when New Zealand's Sarah Nicholson, South Korea's Park Hee-young and Australia's Katherine Hull all shot 71s.

Defending champion Karrie Webb had a 1-under 72 and was a stroke further back in a group of six.

"It was not the nice, sunny day you'd like to play for your first round of the year but I'll take 1-under," Webb said. "I am pretty happy with the way things turned out."