The impact of the human immunodeficiency virus (HIV) epidemic in sub-Saharan Africa on future mortality rates of infants, children, and mothers, life expectancy, and economic growth is profound. Vertical transmission of HIV, transmission from mother to child, is a major factor in the increasing rates of HIV infection in sub-Saharan Africa. Vertical transmission of HIV occurs in utero, intrapartum during labor and delivery, and postpartum during breast-feeding. Because of the large numbers of HIV-infected mothers in developing countries, the majority trials regarding prevention of vertical transmission of HIV have been conducted in sub-Saharan Africa. Thus, sub-Saharan Africa has become a human laboratory, which demonstrates both the successes and failures of preventative methods to reduce vertical transmission of HIV. This review summarizes the body of research dedicated to understanding the pathophysiology of vertical transmission of HIV and pharmacology of inhibition of vertical transmission of HIV, While many debate the ethics of conducting trials in developing countries where effective prevention modalities have been slow to be implemented for economic, social and political reasons, studies continue and researchers continue to discover therapies and preventative methods, which may reduce the future devastation of HIV both in sub-Saharan Africa and throughout the world. Target Audience: Obstetricians & Gynecologists, family Physicians Learning Objectives: After completion of this article, the reader will be able to list the factors that affect the vertical transmission of HIV during pregnancy, to outline potential methods to decrease the vertical transmission of HIV, and to summarize the ethical considerations surrounding the use of patients from sub-Saharan Africa in HIV prevention trials.