The incidence of sterilisation in the UK

To estimate incidence rates for tubal occlusion and vasectomy, and to examine how these vary with age, geographical area and time.

Search of patient files for operation codes in the years 1992-1999 and calculation of person time.

General Practice Research Database.

Patient files of women aged 20-54 years and men aged 20-64 years were searched for sterilisation operation codes. Annual incidence rates in five year aged bands were calculated for sterilisation operations for both sexes. Figures were examined according to National Health Service Region and population density category of the general practices. The relationship between year of operation and mean age at operation was also examined.

Incidence rates by year, age group and geographical area.

The average annual incidence of sterilisation in the eight year period was 4.75 per 1000 person years at risk for women aged 20-54 and 4.48 per 1000 person years at risk for men aged 20-64. For women, there was a statistically significant 30% decrease in incidence of tubal occlusion over the study period. There was no change in vasectomy rates over time. About one-third of all vasectomies in the UK are estimated to be performed outside hospital and community clinic settings. The rates of sterilisation in both sexes were much lower in Greater London than elsewhere in the UK.

The popularity of tubal occlusion appears to be on the decline. Since 1996, the UK has been one of very few countries in which sterilisation incidence in men is greater than that in women.