While national researchers say sexual activity is soaring among young American women, local health officials believe that's one trend Utah youths aren't following.

Researchers at the Centers for Disease Control in Atlanta released a new survey Friday stating that 51.5 percent of American women age 15 to 19 reported having premarital sex. That's nearly double the 28.6 percent of youths who reported sexual activity in 1970. (See accompanying story.)Dr. Harry Gibbons, director of the Salt Lake CityCounty Health Department, said he hadn't seen the new CDC study but wondered about the methodology used to conduct the study of 8,450 women between 15 and 44 years old. He said more rural states and those with less racially diverse populations, such as Utah, might have different rates of sexual activity.

"It may be true, but I still don't think it reflects Utah," Gibbons said. "Utah usually lags considerably behind in this kind of thing."

Dr. Suzanne Dandoy, director of the Utah Department of Health, agreed with Gibbons that the number of sexually active teenagers seemed high for Utah. "That just strikes me as high.

"I would be surprised if we're talking about premarital sexual activity. What you have to remember is we have women married a lot earlier here."

Stan Weed, a Kearns psychologist, was a member on the Governor's Task Force for Prevention of Teenage Pregnancy. The task force released a 82-page report in 1988, which included results of a controversial survey of 839 Utah high school students questioning their sexual habits.

"Generally, our figures (for teenage sexual activity) in the state have been around 10 percent to 15 percent lower for any given age group or gender," Weed said.

Determining sexual activity based on self-reported studies can by misleading, Weed said. And most surveys lump teenagers who have experimented with sexual intercourse once in the same category as those who are sexually active on a regular basis.

But Xan Kali, a social worker in the maternity ward at LDS Hospital, said she thinks sexual activity is rising among Utah teenagers. "I definitely have seen an increase," in the past year, she said. "A lot of them won't come out and talk about (sexual activity) because of their religious preferences and fear of embarrassment to themselves and family members.

"Teenage youths here are becoming as sexually active as their counterparts nationwide."