TORONTO - The teen pregnancy and abortion rates in Canada are the lowest in more than a decade, but that doesn't mean the country's youth is practising safe sex.

A recent study shows the pregnancy rate for Canadian teens 15-to 19-years-old has been on a continuous decline, dropping from 49.2 pregnancies per 1000 in 1994 to 32.1 in 2003.

Abortion rates have shown a similar trend in the same time frame, dropping from 22.1 to 17.1 in 2003.

But in what seems like a contradiction, the same social climate that gave rise to fewer pregnancies and abortion may also be responsible for an increasing rate of sexually transmitted infections (STIs), that includes chlamydia, gonorrhea, syphilis, human papillomavirus (HPV) and HIV.

Alex McKay, the research co-ordinator at the Sex Information and Education Council of Canada, authored the study on teen pregnancy which was published in the spring. He said the declining numbers imply an overall improvement in sexual health among teens.

"It's pretty clear that a declining teen pregnancy rate is a signal that not only are young women increasingly empowered but also that they are making positive decisions around things like employment opportunities, educational aspirations, and are living in an environment where they are able to pursue those kinds of things," he said.

In his study, McKay looked at teenage birth and abortion rates in Canada, the United States and Britain. While all three countries showed a decline in both, Canada had the lowest birth and abortion among teens.

Feminists, who have spent decades working to ensure future generations of women had the opportunity to control their own destinies and sexual health, are now able to take pride in their accomplishments.

"The woman's movement fought for many years for sex education in the schools, for available and affordable birth control and for the right to abortion. We won those demands, probably more successfully than anywhere else in the world," said social activist Judy Rebick, former president of the National Action Committee on the Status of Women.

"And now it is paying off."

But the dividends don't extend into all areas of sexual health. In another study, the Sex Information and Education Council of Canada found that "STIs disproportionately affect adolescents."

The chlamydia rate, for example, rose from 1095.1 infections per 100,000 in 1991 to 1378.6 in 2002.

Chlamydia infections increase the risk of HIV infection and, if untreated, can result in pelvic inflammatory disease, infertility and ectopic pregnancy.

The study reported 40 per cent to 70 per cent of chlamidial infections have no noticeable symptoms, which means the rate is most likely higher than reported.

"However, it is very clear from the available data from many sources from Canada and other countries, the actual prevalence of chlamydia among the youth and young adult population may not be increasing but is remaining stable at a dangerously high level," McKay said

And experts feel serial monogamy may be to blame.

McKay said that, for the most part, younger teens take safe sex very seriously.

It's when teens get older and involved in more serious relationships that condoms are replaced with birth-control pills.

While pregnancies are avoided, the couples no longer practice safe sex.

Stephanie Sersli, manager executive services at Options for Sexual Health in Vancouver, agrees that once teens are committed in a relationship, they tend to use oral contraception, yet fail to get tested for STIs.

"I don't think we've gotten to the point where regular STI testing is considered an integral part of your sexual health," she said from Vancouver.

"Women know they need to go for a Pap (test) every year and that's just a regular part of your maintenance. I don't think we've gotten to that point with STI testing yet."

She said sexual health educators and advocates need to help change that mentality and make STI testing a part of a yearly check up.

Rebick believes couples - young and old - have a blind trust when it comes to love.

"People have this illusion that if they're are in a monogamous relationship, they're not at risk of (sexually transmitted infections)," she said. "But of course monogamous relationships don't always stay that way."

McKay said that once a relationship ends, the person usually falls into another committed relationship and condom use again gives way to oral contraception.

When you take into account most Canadians start sexual relationships at 16 and put off marriage until their mid-to-late twenties, he said most Canadians are serial monagamists, having unprotected sex with several partners in their lifetime.