Trends in the incidence of ectopic pregnancy in England and Wales from 1966 to 1996

Objective To examine the incidence of ectopic pregnancy over the period 1966 to 1996.
Setting England and Wales.
Design Use of official statistics on hospital discharges, maternities, legal abortions and estimated populations of women aged 15–44 years.
Main outcome measures Incidence rates of ectopic pregnancies.
Results Between 1966 to 1970 and 1994 to 1996 the recorded incidence increased 4.5-fold from 3.45 to 15.5 per 1000 maternities, 3.8-fold from 3.25 to 12.4 per 1000 pregnancies and 3.1-fold from 30.2 to 94.8 per 100,000 women aged 15–44. The rate of increase was not uniform. Incidence approximately doubled between 1966 and 1985, when the official data collection system changed. By 1989, when data from the new system became available, there had been a further almost doubling of recorded incidence. Subsequently, the upward trend appears to have continued until 1991 to 1992 and has remained stable in the last four years of the study. The trends were similar in each of three 10-year age groups.
Conclusions The recorded incidence of ectopic pregnancy has increased markedly over the last three decades. This may be partly due to artefacts of data recording and more sensitive diagnostic tests, but it is likely that the actual incidence has increased, probably due to a sexually transmitted agent.