Latest figures show that the number of 15- to 17-year-olds falling pregnant in Derbyshire during 2009 was 477.
It was a reduction of 1.6 per cent on the previous year and the lowest since 2002.
The number of girls in the age group becoming pregnant during 2009 was 33.3 per 1,000.
The figures are better than the national rate of 38.2 per 1,000 and the East Midlands rate of 37.7.
Cllr Barry Lewis, Derbyshire County Council cabinet member for young people, said: “We’re pleased that numbers have fallen again. We’ve worked hard alongside our partners to make sure that teenagers have improved access to sexual health services and good quality sex and relationship education.
“Parents and carers often feel uncomfortable speaking to their children about sexual health matters so we’ve offered support and advice to make it easier.”