HIV/AIDS remains a significant health challenge in Kenya, particularly affecting pregnant women who are at higher risk of transmission to their infants. A comparative study design was employed, utilising data from health records and surveys conducted among participants enrolled in various HIV/AIDS prevention programmes. Data were analysed using statistical methods to identify trends and differences across the programmes. Amongst pregnant women participating in the study, a significant proportion (34%) of those who received comprehensive support services had reduced viral loads compared to those who did not receive such services, indicating improved health outcomes. The findings suggest that comprehensive HIV/AIDS prevention programmes significantly improve health outcomes for pregnant women in Nairobi's CBDs, with particular benefits observed among participants receiving full-service support. Further research should be conducted to explore long-term impacts and identify areas where services can be improved. Policymakers are encouraged to implement more holistic interventions that include comprehensive care packages for HIV/AIDS prevention programmes targeting pregnant women in urban settings.