[Reduced number of extrauterine pregnancies--increased fertility of women during the 1990s?].
BACKGROUND
The purpose of this study was to investigate trends in ectopic pregnancy in relation to fertility patterns in general.


METHODS
All women hospitalised with ectopic pregnancy in Sør-Trøndelag county 1970-2002 were identified through hospital discharge registries (ICD-8, -9, -10). Medical records were reviewed in order to identify patients who were residents of the county and had ectopic pregnancy verified by histology. Incidence rates were analysed by age, previous ectopic pregnancy and previous infertility treatment. Cumulative incidence rates were analysed by birth cohort. Ectopic pregnancy related to the number of births (extrauterine ratio) was analysed by age and parity.


RESULTS
The incidence of ectopic pregnancy (per 10 000 women-years) increased from 4.2 in 1970-74 to 15.1 in 1990-94, then declined to 6.5 in 2000-02. Women 25-34 years old had highest incidence rates throughout the whole study period and the sharpest decline after 1990-94. The proportion of women with previous ectopic pregnancy or previous infertility declined after 1990-94. Cumulative incidence rates by age 30 were lowest for the youngest cohorts. The extrauterine ratio increased by age throughout the whole period and decreased in all age and parity specific groups throughout the 1990s.


CONCLUSIONS
After the epidemic increase in ectopic pregnancy observed from 1970 to the end of the 1980s, the annual number of cases has declined sharply. The observations indicate better primary treatment for primary ectopic pregnancy and primary infertility and improved female fertility through the 1990s.
Bakken
Inger Johanne
IJ
Seksjon for epidemiologisk forskning, SINTEF Unimed, 7465 Trondheim. inger.j.bakken@sintef.no
Skjeldestad
Finn Egil
FE
D000293:Adolescent; D000328:Adult; D005260:Female; D005298:Fertility; D006801:Humans; D015994:Incidence; D007247:Infertility, Female / Q000453:epidemiology*; D009664:Norway / Q000453:epidemiology; D011247:Pregnancy; D011271:Pregnancy, Ectopic / Q000453:epidemiology*; D012042:Registries