What is the term for scanty menstruation?

Hypomenorrhea: The Medical Term for Scanty Menstruation

Hypomenorrhea is the medical term for scanty menstruation, characterized by abnormally light menstrual flow while maintaining regular intervals between periods.

Definition and Characteristics

Hypomenorrhea refers to menstrual periods that are:

• Abnormally light in flow
• Regular in timing (unlike oligomenorrhea which refers to infrequent periods)
• May include very light bleeding, shorter duration, or reduced volume
• May be accompanied by premenstrual and postmenstrual spotting 1

Differential Diagnosis of Menstrual Flow Disorders

It's important to distinguish between different menstrual disorders:

• Hypomenorrhea: Scanty/light menstrual flow with normal cycle intervals
• Oligomenorrhea: Infrequent menstruation (cycles lasting 36-90 days) 2
• Amenorrhea: Absence of menstruation for ≥4 months or primary amenorrhea by age 16 1
• Polymenorrhea: Increased menstrual bleeding or frequency 3

Causes of Hypomenorrhea

Hypomenorrhea can result from various physiological and pathological conditions:

Hormonal Factors

• Relative Energy Deficiency in Sport (RED-S): Athletes with low energy availability may experience very light bleeding 1
• Functional Hypothalamic Amenorrhea (FHA): Can present with very light bleeding before progressing to amenorrhea 1
• Thyroid dysfunction: Both hyper- and hypothyroidism can cause menstrual disturbances 3
• Hormonal contraceptive use: Can reduce menstrual flow as a desired effect 1

Structural/Anatomical Factors

• Asherman's syndrome: Intrauterine adhesions
• Endometrial hypoplasia: Thin endometrial lining
• Previous uterine procedures: Such as endometrial ablation

Other Factors

• Low body weight/weight loss: Rapid or significant fat mass reduction can compromise menstrual function 1
• Stress: Psychological stress can affect hypothalamic function and menstrual patterns 1
• Excessive exercise: Particularly in athletes, can lead to menstrual disturbances 1

Evaluation of Hypomenorrhea

When evaluating scanty menstruation, consider:

Clinical Assessment

• Menstrual history: Duration, frequency, and amount of flow
• Weight changes: Recent weight loss or very low BMI
• Exercise patterns: Intensity and frequency
• Stress levels and psychological factors
• Medication use, particularly hormonal contraceptives

Laboratory Evaluation

• Hormonal profile: FSH, LH, estradiol, progesterone, prolactin, TSH 4
• Progesterone levels: <6 nmol/l during mid-luteal phase suggests anovulation 4
• Androgens: Testosterone, DHEAS if hyperandrogenism suspected 4

Imaging

• Pelvic ultrasound to evaluate endometrial thickness and rule out structural abnormalities 4

Management Approach

Management depends on the underlying cause and the patient's reproductive goals:

For Lifestyle-Related Causes

• Increase caloric intake if low body weight or energy deficiency is present
• Modify exercise regimen if excessive
• Stress management techniques

For Hormonal Imbalances

• Treat underlying thyroid dysfunction if present
• Consider hormonal therapy if indicated
• For athletes with RED-S: Address energy availability issues 1

For Structural Causes

• Surgical management may be required for conditions like Asherman's syndrome

When to Refer

Consider referral to gynecology or endocrinology when:

• Hypomenorrhea is accompanied by other concerning symptoms
• Laboratory evidence of significant hormonal imbalances 4
• Structural abnormalities are identified on imaging
• Symptoms persist despite initial management

Common Pitfalls

• Overlooking the significance: Dismissing scanty periods as "convenient" without investigating potential underlying conditions
• Misdiagnosis: Confusing hypomenorrhea with oligomenorrhea or early stages of amenorrhea
• Incomplete evaluation: Failing to consider both hormonal and structural causes
• Not addressing lifestyle factors: Particularly in athletes or those with disordered eating patterns

Hypomenorrhea may be an early indicator of more serious conditions like premature ovarian insufficiency or functional hypothalamic amenorrhea, so thorough evaluation is warranted, especially when accompanied by other symptoms or when it represents a change from previous menstrual patterns.