Using contraception is the most effective way to prevent pregnancy when engaging in sexual intercourse, but people struggle to use it because they understand that every single act of intercourse without contraception may not lead to pregnancy and dissatisfaction with side effects can lead to stopping effective prescription methods. Research shows that risk preferences and perceptions affect behavioral intentions and actions when side effects are at issue. Importantly, the relationship between risk preferences and side effects can affect behavior at three important decision points: 1) the decision to begin a prescription contraceptive method, 2) the decision to stop or switch a method because of dissatisfaction, and 3) the decision to resume method use after a non-use spell. Addressing the relationship between desire to avoid pregnancy, experiences and perceptions of side effects, and risk preferences therefore may be helpful in understanding why people forego using prescription contraceptives due to side effects when they do not desire pregnancy. Completing the project will build an evidentiary base demonstrating the interconnection between side effects, risk preferences, and contraceptive behavior that can aid efforts to help clinicians understand the seriousness of side effects for patients and help identify patients who may be particularly likely to stop or not begin prescription contraception so that clinicians may develop tailored approaches to address their concerns.