Background: New administration forms for hormonal contraception and a higher patient's charge for sterilisation of women have changed the pattern of contraceptive use in Norway.
Material and methods: In October 2005, more than 5,000 women listed in a Webpanel of more than 50,000 subscribers were invited to participate in survey on contraceptive use. The response rate was 41%. 1,575 women, aged 20- 44 years, who were sexually active the last three months before the interview, did not plan to become pregnant and defined themselves as fertile were eligible for analysis.
Results: Over 90% of the respondents had used at least one contraceptive method during the last three months. 9% did not use contraceptives, 6% used "safe periods/coitus interruptus", whereas 13% used condom. 38% had used hormonal contraception, 23% intrauterine devices (hormonal IUD included) and 8% of the women were sterilized. The new administration forms of hormonal contraception; like contraceptive plaster, vaginal ring and implants had few users. Among hormonal users oral contraceptives dominates in all age groups. There were twice as many hormonal IUD users as cooper IUD users in all age groups.
Interpretation: The Webpanel of women aged 20-44 years is fairly representative of Norwegian women, when compared with census data from Statistics Norway. Compared with previous contraceptive surveys in Norway, there are more users of hormonal contraceptives, predominantly oral contraceptives. The user rate of IUDs is fairly stable; but more women use hormonal IUDs than copper IUDs and fewer women are sterilized.