The main objective of the study was to assess the utilisation of prevention of mother-to-child transmission (PMTCT) services among mothers registered for services at Nyanza Provincial Hospital in Kenya.A crosssectional exploratory study was conducted, using both quantitative and qualitative approaches to collect primary and secondary data.The study population was 133 clients registered for PMTCT services.The study revealed that 52.4% of clients received PMTCT information at the health facility without prior knowledge about intervention, 96% waited for more than 90 minutes, and 89% took less than 10 minutes for post-test counselling. Knowledge of MTCT and PMTCT was inadequate even after counselling, as participants could not recall the information divulged during counselling. In addition, 80% of clients did not present for follow-up counselling irrespective of HIV status, and 95% did not disclose positive HIV status to spouses/relatives for fear of stigma, discrimination and violence. Inadequate counselling services delivered to clients affected service utilisation, in that significant dropout occurred at the stages of HIV result (31.5%), enrollment (53.6%), and delivery (80.7%). Reasons for dropout included fear of positive HIV result, chronic illness, stigma and discrimination, unsupportive spouse and inability to pay for the services