Taking a Menstrual History Using the MIDAS Framework
The MIDAS framework (Menarche, Interval, Duration, Amount, Symptoms) provides a systematic approach to obtaining a complete menstrual history, which should be documented at every well visit for adolescent and adult women as the menstrual cycle serves as a vital sign.
The MIDAS Components
M - Menarche
- Age at first period: Document the specific age when menstruation began
- Context: Early menarche (≤10 years) is associated with shorter cycles, increased dysmenorrhea, and different bleeding patterns compared to later menarche 1
- Clinical significance: Helps establish gynecologic age (years since menarche), which is critical for interpreting cycle characteristics, especially in adolescents 1
I - Interval (Cycle Length)
- Ask: "How many days from the start of one period to the start of the next?"
- Normal range: 21-45 days in adults; more variable in adolescents, especially within first 1-3 years post-menarche 2
- Red flags:
D - Duration (Period Length)
- Ask: "How many days does bleeding typically last?"
- Normal range: 2-7 days
- Document: Whether duration is consistent or variable cycle-to-cycle
A - Amount (Flow Volume)
- Assess subjectively: Light, moderate, heavy, or very heavy
- Specific questions:
- "Do you soak through pads/tampons in <2 hours?"
- "Do you pass clots larger than a quarter?"
- "Does bleeding interfere with daily activities?"
- Clinical note: Heavy flow becomes more common with increasing gynecologic age 1
S - Symptoms
Document associated symptoms systematically:
Pain/Dysmenorrhea:
- Severity (mild/moderate/severe)
- Impact on activities (school/work absences)
- Early menarche is associated with increased dysmenorrhea 1
Other menstrual symptoms:
- Premenstrual symptoms (mood changes, bloating, breast tenderness)
- Gastrointestinal symptoms
- Headaches
- Fatigue
Key Clinical Considerations
Adolescents Require Special Attention
- Irregular cycles are physiologically normal in the first 1-2 years post-menarche (85% anovulatory in year 1,59% in year 3) 3
- Do not diagnose PCOS in adolescents based solely on irregular cycles or polycystic ovaries 3
- Persistent oligomenorrhea ≥2 years post-menarche with hyperandrogenism warrants PCOS evaluation 3
Documentation Gaps Are Common
Research shows menstrual history documentation is frequently incomplete, with rates varying significantly by specialty 4, 5. Adolescent Medicine providers are 6.44 times more likely to document complete menstrual histories than Family Medicine and 5.80 times more likely than Pediatrics 4.
When to Evaluate Further
Initiate diagnostic workup when:
- Cycle interval persistently exceeds 45 days 2
- Amenorrhea for ≥3 months 2
- Primary amenorrhea by age 15 or 3 years post-thelarche
- Severe dysmenorrhea unresponsive to NSAIDs
- Heavy bleeding causing anemia or significantly impacting quality of life
Additional History Elements
Beyond MIDAS, obtain:
- Last menstrual period (LMP): Most commonly documented element but insufficient alone 5
- Sexual history: Pregnancy risk, contraception use, STI risk
- Contraceptive use: Current and past methods affect bleeding patterns 6, 7
- Family history: PCOS, bleeding disorders, early menopause 3
- Psychosocial factors: Stress, eating disorders, excessive exercise (for functional hypothalamic amenorrhea) 2
- Medications: Anticoagulants, hormones, psychotropics
Practical Implementation
At every well visit, systematically document all five MIDAS components. This structured approach ensures comprehensive assessment and facilitates tracking changes over time. The menstrual cycle provides critical information about overall health status and should be treated with the same importance as other vital signs 8.
For patients on contraception, counsel about expected bleeding patterns specific to their method and reassure that irregular bleeding is often not harmful, particularly with progestin-only methods 6, 7.