Dual protection against unintended pregnancy and sexually transmitted infections: what is the best contraceptive approach?

In the midst of the global epidemics of both unintended pregnancy and sexually transmitted infection, contraceptive options that provide dual protection are ideal. However, those contraceptives with the best record of preventing pregnancy under typical use conditions (sterilization, hormonal methods, intrauterine devices) provide little if any protection against sexually transmitted infection. Alternatively, barrier contraceptive methods (specifically, condoms), which can reduce risks of many sexually transmitted infections, are associated with relatively higher pregnancy rates for most users than other contraceptives. This situation has produced a dilemma for those wishing to promote dual protection: whether to advocate use of two methods (one primarily to prevent pregnancy and the other primarily to prevent infections) or whether to emphasize use of condoms for both purposes. Data comparing these two approaches are limited and often contradictory. We discuss the underlying concepts of exposure to both pregnancy and infection, provide a broad overview of the effectiveness of contraceptive methods against these two conditions, present approaches to optimize dual protection, and propose several new directions for necessary research. In the absence of evidence-based recommendations, we believe clinicians should assist clients in assessing their likelihood of exposure to infection, either by prevalence of sexually transmitted infection in the community or by the specific risk factors of the client. If exposure is likely, particularly to the more serious infections such as human immunodeficiency virus, the one-method approach should be given greater weight. However, in settings where unintended pregnancy is the greater concern, emphasizing the two-methods approach as a first option may be appropriate.