More Reliable National Data on Abortions Needed
There are no comprehensive data currently available for deriving accurate numbers of induced abortions taking place in Australia each year.
In an article in the latest issue of the Medical Journal of Australia, researchers Annabelle Chan and Leonie Sage of the Pregnancy Outcome Unit, SA Department of Health, have attempted to estimate Australia's annual abortion rates, from 1985 to 2003, among women aged 15-44 years.
Legislation on abortion varies from state to state. Statistics are routinely collected only in states with legislation requiring notification of abortions. The states with specific legislation or mandatory notification are South Australia, the Northern Territory and Western Australia.
The authors based their estimates of induced abortion rates on Medicare claim statistics (for private patients) and hospital morbidity statistics (for public patients). However, as both of these sources presented problems with interpretation, they used a variety of different approaches to produce their final estimates.
Firstly, SA hospital morbidity statistics were compared with SA statutory notifications of abortions to estimate the accuracy of these collections. Publicly available Medicare statistics on abortion procedures performed on private patients in South Australia were then compared with hospital morbidity statistics for private patients. Finally, national statistics on abortion derived from national Medicare and hospital morbidity statistics were adjusted for inaccuracies found in these sources.
One of the problems the authors faced was that there is currently no single Medicare Benefits Schedule item number for induced abortion. The item number most commonly used could include procedures for missed abortion, where the fetus has died spontaneously but remained in the uterus. The use of this item number therefore overestimates the number of abortions claimed on Medicare.
Another factor that caused overestimation of abortions in hospital morbidity statistics was that re-admission of a woman to hospital after an abortion procedure would also be recorded as an abortion (because of being assigned the same 'principal diagnosis' code).
However, Medicare statistics could also underestimate the number of abortions as studies involving women who attended private clinics for abortion have shown that a proportion do not claim as they do not have Medicare cards or for reasons of privacy.
The authors estimate that Australia's abortion rate increased from 17.9 per 1000 women aged 15-44 in 1985 to a peak of 21.9/1000 in 1995, then declined to 19.7/1000 in 2003, when the estimated number of abortions was 84,460 They stress that these are only estimates and accurate numbers cannot currently be obtained.
The authors suggest working towards a de-identified national collection of abortion statistics that might include characteristics of the women, previous obstetric history, gestation and other relevant factors. A list of agreed data items could be recorded by both hospitals and private clinics and combined into a national body of data.
An attempt to collect the data retrospectively for 2003 or 2004 for states without specific abortion legislation would demonstrate the feasibility of this approach, say the authors.
The Medical Journal of Australia is a publication of the Australian Medical Association.
CONTACT Dr Annabelle CHAN 08 8226 6488
Judith TOKLEY, AMA Public Affairs, 0408 824 306 / 02 6270 5471