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Recommendations for standardization of bleeding data analyses in contraceptive studies
Mitchell D Creinin1, Carolina Sales Vieira2, Carolyn L Westhoff3
1Department of Obstetrics and Gynecology, University of California, Davis, Sacramento, CA, United States.
Insights
New recommendations standardize menstrual bleeding data for contraceptive research. Standardized criteria for bleeding pattern, flow, and duration improve user and clinician understanding of contraceptive side effects.
Area of Science:
- Reproductive Health
- Contraception Research
- Clinical Trial Methodology
Background:
- Existing definitions for menstrual bleeding changes with contraceptive use lack standardization.
- This ambiguity hinders clear communication and comparison of contraceptive method outcomes.
Purpose of the Study:
- To develop standardized recommendations for analyzing menstrual bleeding data in contraceptive research.
- To improve information provided to users, clinicians, researchers, pharmaceutical companies, and regulatory agencies.
Main Methods:
- A panel convened to establish new criteria for bleeding outcomes.
- Proposed criteria include pattern, flow, and duration, with specific descriptors for predictable and unpredictable bleeding patterns.
- Recommended study durations vary by contraceptive type (e.g., 12 months for short-acting, 2 years for injectables).
Main Results:
- Introduced three independent criteria: bleeding pattern (quantifying scheduled, unscheduled, or frequency), flow (patient-reported comparison to typical flow), and duration (prolonged episode >7 days).
- Defined specific assessment durations for various contraceptive regimens to ensure comprehensive data collection.
- Standardization allows for better understanding of bleeding profiles and product differences.
Conclusions:
- Standardized assessment of bleeding pattern, flow, and duration provides a comprehensive understanding of contraceptive-related bleeding outcomes.
- This standardization facilitates improved study comparisons, data synthesis, and informed decision-making for contraceptive users and providers.
Abstract:
To address limitations that exist with existing definitions of menstrual bleeding changes that occur with contraceptive methods, we assembled a panel to develop new recommendations for standardization of bleeding data analyses associated with contraceptive use to better inform users, clinicians, investigators, pharmaceutical companies, and regulatory agencies. We propose three criteria for assessing bleeding outcomes: pattern, flow, and duration. The descriptors within each criterion depend on whether the contraceptive is designed to result in a predictable or unpredictable bleeding pattern. Predictable pattern outcomes quantify days of scheduled, unscheduled and no bleeding, while unpredictable pattern outcomes assess frequency. Flow is quantified based on patient comparisons to their typical flow when not using contraception, with spotting representing no menstrual products use. Duration of a prolonged bleeding and/or spotting episode is more than 7 days. Studies should assess bleeding characteristics for a minimum of 12 months for 21/7, 24/4, extended cycle or continuous regimens, two years for injectables, and the full duration of use for long-acting contraceptives. Describing pattern, flow and duration as independent categories allows a fuller understanding of the bleeding outcomes and better future assessments of acceptability and continuation. Standardization of outcomes permits better comparison between studies and data synthesis; standardization will also improve the ability of clinicians and patients to understand differences between products.
