Date of Award
Selective Evidence-Based Medicine Review
Master of Science in Health Sciences - Physician Assistant
Physician Assistant Studies
Laura Levy, DHSc, PA-C
Objective: The objective of this selective evidence-based medicine (EBM) review is to determine whether or not the combined oral contraceptive treatment of 150 mcg levonorgestrel and 30 mcg ethinyl estradiol is effective in preventing unscheduled uterine bleeding.
Study Design: Review of two randomized controlled trials (RCTs) and one post hoc analysis, published after 2014 all in the English language.
Data Sources: Two randomized controlled trials (RCTs) and one post hoc analysis, all of which evaluate the efficacy of the combined oral contraceptive (COC) treatment of 150 mcg levonorgestrel and 30 mcg ethinyl estradiol in preventing bothersome unscheduled uterine bleeding. In both RCTs, an experimental group is compared to a control group receiving an identical appearing placebo. All studies were found using PubMed.
Outcomes Measured: Each of the three articles analyzed the effects of the combined oral contraceptive of levonorgestrel and ethinyl estradiol in preventing bothersome unscheduled uterine bleeding. A five-point Likert Scale and bleeding diaries were the methods used to measure bothersome unscheduled uterine bleeding.
Results: In the studies by Guiahi et al.2 and Hou et al.6, participants receiving the treatment of combined oral contraceptive showed statistically significant reduction in unscheduled uterine bleeding compared to the control group with p-values of <0.01 (Guiahi) and 0.03 (Hou). The study by Nappi et al.7 compared participants with 0-6 and >6 days of bleeding and showed significant improvement that increased each 91-day cycle of the combined oral contraceptive treatment with a confidence interval of 95% and an odds ratio (OR) of 1.531.
Conclusions: Based on the systematic review of the two randomized controlled trials and one post hoc analysis, one can decisively say that 150 mcg levonorgestrel and 30 mcg ethinyl estradiol is effective in treating bothersome unscheduled uterine bleeding. All three studies verified statistically significant reduction in bleeding with use of the therapy.
Parker, Brandi L., "Is The Combined Oral Contraceptive Treatment Of 150 mcg Levonorgestrel And 30 mcg Ethinyl Estradiol Effective In Preventing Bothersome Unscheduled Uterine Bleeding?" (2019). PCOM Physician Assistant Studies Student Scholarship. 440.