Increasing adverse birth outcome are a major concern in South African maternal care and globally In South Africa, perinatal mortality rate of 40/1000 and maternal mortality ratio of 150/100 000 are poor considering the fact that 95.1 percent of women attend antenatal care and 83.7 percent of women deliver in a medical facility. This study focuses on the effect of lack of adequate antenatal care on adverse birth outcome using data from the 1998 South African Demographic and Health Survey. The analysis is based on univariate and bivariate analysis to examine the effect of socio- demographic characteristics on adverse birth outcomes. In addition, binary logistic regression is used to examine the impact of antenatal and sociodemographic characteristics on adverse birth outcome. The results show majority of women reporting adverse birth outcome are those who delivered though caesarean section (53 percent) and that most of these women are likely to be educated and have better socio economic status and that they are likely to be Non African. It is also shows that the proportion of women attending antenatal care adequately is very high in South Africa. The results show that the use of antenatal care is determined by a range of socio demographic factors including the level of education and the economic status of the mother. Only timing of antenatal care, place of delivery and race had a significant effect on adverse birth outcome. All other variables were not significant. Results from the binary regression analysis show that women who started their antenatal care during second and third trimester (95%CI: 0.211-0.975), were Non African (95%CI: 1.082 to 2.098) and delivered in a private health facilities (95%CI: 0.28 to 0.73) were more likely to have adverse birth outcome compared to their counterparts. Most women choosing caesarean section do so without adequate information on the disadvantages of delivering through caesarean section. Therefore, there is a need to focus maternal health education to all women in South Africa regardless of their socio- economic status background