Effera Dose Response: Women's Health

Inclusion Criteria: Participants must meet all of the following criteria to be eligible for participation: * Women, 18 - 40 years of age * No changes in hormonal contraception use in the past 6 months * Regular or mildly irregular cycles (24-45 days) for the past 3 months * In the majority (\>3) of menstrual cycles over the past 6 months, experience menstrual cramps on a pain scale of at least 4 out of 10 (1=no pain at all and 10 = worst pain ever experienced) * In the majority (\>3) of menstrual cycles over the past 6 months, experience pain so significant that it requires over-the-counter pain medication for at least 2 days (on average) per period * In the majority (\>3) of menstrual cycles over the past 6 months, experience at least one day per cycle where menstrual symptoms either interfere with work or school performance, limit normal daily activities or exercise, or lead to staying home, leaving early, or modifying plans * Reports noticeable mood or physical changes in the 5-7 days before menses in most cycles (irritability, mood, bloating, breast tenderness, cravings, sleep changes, etc.) * Generally healthy and free of diseases or disorders that impact functioning of the gastrointestinal system. * No recent or acute infection in the past 30 days and no chronic systemic illness * No psychiatric condition that, in the investigator's judgment, would impair consent capacity, protocol adherence, or valid completion of questionnaires. * If psychiatric medication is used: …