Objective  In 1996 termination of pregnancy was legalised in South Africa. This article examines the impact of age on the epidemiology of incomplete abortion after legislative change. It draws comparison with the findings of a similar study undertaken in 1994.

Design  Multicentre, prospective, descriptive study.

Setting  Forty-seven public hospitals in all nine provinces.

Sample  A stratified random sample of all hospitals treating gynaecological emergencies was drawn. All women of gestation under 22 weeks who presented with incomplete abortion during three weeks of data collection in 2000 were included.

Methods  A data capture sheet completed by a clinician from the case notes.

Main outcome measures  Demographic characteristics and clinical findings on admission by age of women.

Results  Overall, there was a significant increase in the proportion of cases with no signs of infection on admission (from 79.5% to 90.1%) and a significant decrease in evidence of interference on evacuation (4.5% to 0.6%) between 1994 and 2000. Substantial age differentials were seen. Women over 30 were significantly less likely than those 21–30 years or under 21 to be low severity (65.5%vs 75.2%vs 76.4%, P= 0.0087) and more likely to have offensive products (16.3%vs 6.0%vs 6.4%, P= 0.01) than the younger women.

Conclusions  Legalisation of abortion had an immediate positive impact on morbidity, especially in younger women. This is an important change as teenagers had the highest morbidity in 1994. The trend is supported by evidence from the 1999–2001 Confidential Enquiry into Maternal Deaths, which further suggested that abortion mortality dropped by more than 90% since 1994.