OBJECTIVES: Despite a shift towards other screening modalities, cervical cytology still has an important screening
function in many settings. The worldwide human immunodeficiency virus (HIV) epidemic has impacted severely
on cervical cancer, resulting in women presenting at a younger age with more advance disease and poorer
prognosis. The objective of this study was to compare different datasets from different time periods to assess
the possible impact of HIV infection on the epidemiological characteristics of conventional cervical cytology
DESIGN: The design was a comparative overview of two different cervical cytology datasets collected at different
SETTINGS AND SUBJECTS: Conventional cervical cytology screening data from non-pregnant patients at the
gynaecological outpatient service of the Pretoria Academic Complex from 1991-2000, and data from pregnant
patients attending the Kalafong Hospital antenatal clinic in 1993-1994 and 2008, were analysed.
OUTCOME MEASURES: Abnormal smear rates, the distribution of different abnormal smears and HIV prevalence
in pregnant women taking part in the annual, National Antenatal Sentinel HIV and Syphilis Prevalence Survey.
RESULTS: The high prevalence of HIV in South Africa is associated with a higher prevalence of abnormal smears. It is
also associated with a change in the distribution of detected abnormalities. High-grade squamous intraepithelial
lesions (HSIL) are now much more common than low-grade squamous intraepithelial lesions (LSIL). The most
pronounced change has been a shift in the ratio of LSIL to HSIL, where the value has changed from > 1 to < 1.
CONCLUSION: The rate of abnormal smears as well as the distribution of abnormalities of conventional cervical
cytology in South Africa has changed. It is possible that this change is associated with the high prevalence of HIV