Teenage girls were less likely to have two or more children in 2003 than they were a decade earlier, Statistics Canada reported Wednesday.

Nonetheless, an estimated 25,000 teenage women gave birth to their second or subsequent child between 1993 and 2003, the agency said.

In 2003, the rate of live births among 15- to 19-year-olds (14.5 live births per 1,000) was about one-seventh the rate for women aged 25 to 34 (96.1 per 1,000 women) — the age group with the highest fertility rate

The fertility rate among teens has been falling steadily since the mid-1970s, according to the report.

Teens who had two or more children were concentrated in low-income neighbourhoods.

Early childbearing can have consequences for both the babies and mothers.

For example, a newborn's chances of survival depend on large part on its birthweight, with those weighing less than 2,500 grams at birth showing higher mortality and health problems than normal birthweight babies.

Birth rates differed across Canada

The rate of second or subsequent births among teens varied across Canada, with Nunavut having 12 times the national average between 2001 and 2003.

In Manitoba and Saskatchewan, the rate was nearly three times the national average.

"Provinces and territories with high rates of second or subsequent births to teens tended to have relatively large numbers of aboriginal residents," the report said.

Rates were below the national average in Nova Scotia, Quebec and British Columbia.

The study looked at all provinces except Ontario. Since the province introduced birth registration fees in 1996, an estimated three per cent of births may not have been registered, particularly children born to teenage mothers, the report said.