Menstrual Disorders

Normal Cycle & AUB Basics - Period Primer

• Menstrual Cycle Phases: Governed by Hypothalamic-Pituitary-Ovarian (HPO) axis.
  • Follicular (Estrogen ↑): Ovarian follicle maturation; endometrial proliferation.
  • Ovulatory (LH surge): Oocyte release from dominant follicle.
  • Luteal (Progesterone ↑): Corpus luteum forms; prepares endometrium for implantation.
  • Menstruation: Endometrial shedding due to hormone (estrogen & progesterone) ↓ if no implantation.
• Normal Parameters (Adolescents):
  • Cycle Length: 21-45 days (initially irregular, stabilizes to 21-35 days).
  • Duration of Flow: 2-7 days.
  • Blood Loss: < 80 mL/cycle.
• AUB (Abnormal Uterine Bleeding): Any bleeding outside normal volume, regularity, timing, or duration.
  • Classified by 📌 PALM-COEIN system.
    • PALM (Structural): Polyp, Adenomyosis, Leiomyoma, Malignancy/hyperplasia.
    • COEIN (Non-structural): Coagulopathy, Ovulatory dysfunction, Endometrial, Iatrogenic, Not yet classified.

⭐ Ovulatory dysfunction (often anovulation due to HPO axis immaturity) is the most common cause of AUB in adolescents during the first few years post-menarche. This typically presents as irregular, heavy, or prolonged bleeding (AUB-O).

Amenorrhea - The Absent Flow

• Definition:
  • Primary Amenorrhea:
    • No menses by age 15 with normal Secondary Sexual Characteristics (SSC).
    • No menses by age 13 without SSC.
  • Secondary Amenorrhea:
    • Cessation of menses for ≥3 months (regular prior cycles) OR ≥6 months (irregular prior cycles).
• Key Causes (Exclude Pregnancy First!):
  • Primary: Turner Syndrome (XO, ↑FSH), Mullerian Agenesis (MRKH - XX, absent uterus), Androgen Insensitivity Syndrome (AIS - XY, testes), Kallmann Syndrome (anosmia, ↓GnRH).
  • Secondary: Polycystic Ovary Syndrome (PCOS), Hypothalamic dysfunction (stress, ↓weight, exercise), Prolactinoma, Asherman's Syndrome (uterine adhesions), Premature Ovarian Insufficiency (POI, ↑FSH).
• Diagnostic Flow:

⭐ Mullerian Agenesis (MRKH syndrome) presents with primary amenorrhea, an XX karyotype, normal ovarian function & SSCs, but an absent uterus and upper vagina due to Mullerian duct anomalies.

AUB & Dysmenorrhea - Flow Fights

• AUB (Abnormal Uterine Bleeding): Altered volume, frequency, or duration.
  • Adolescents: Often anovulatory (immature HPO) or coagulopathy (vWD).
  • 📌 PALM-COEIN: Structural (Polyp, Adenomyosis, Leiomyoma, Malignancy); Non-structural (Coagulopathy, Ovulatory, Endometrial, Iatrogenic, Not classified).
  • Ix: CBC, TSH, Pelvic USG. Coag studies if indicated.
  • Rx: NSAIDs, OCPs, Progestins, Tranexamic acid. Iron. Acute: IV estrogen.
• Dysmenorrhea (Painful Menses):
  • Primary: Excess prostaglandins ($PGF_{2\alpha}$). No pelvic pathology. Onset 6-12m post-menarche.
    • Rx: NSAIDs (1st line), OCPs.
  • Secondary: Underlying pathology (endometriosis, fibroids).
    • Rx: Treat underlying cause.

⭐ Anovulatory bleeding is most common AUB cause in teens, often resolves with HPO axis maturation.

PCOS & PMS/PMDD - Cycle Saboteurs

• PCOS (Polycystic Ovary Syndrome):
  • Rotterdam criteria (≥2 of 3):
    • Oligo/anovulation
    • Hyperandrogenism (clinical/biochemical)
    • Polycystic ovaries on USG (>12 follicles 2-9mm/ovary or ovarian volume >10ml)
  • Associations: Insulin resistance, obesity, T2DM, ↑endometrial cancer risk.
  • Labs: ↑LH/FSH ratio (often >2:1), ↑Testosterone, ↑AMH.
  • Management: Lifestyle changes, OCPs, Metformin, Clomiphene, Anti-androgens (Spironolactone).
• PMS/PMDD (Premenstrual Syndrome/Dysphoric Disorder):
  • Cyclical physical, emotional, behavioral symptoms in luteal phase; resolve with menses. PMDD is severe.
  • Symptoms: Mood swings, irritability, bloating, breast tenderness, fatigue.
  • Diagnosis: Symptom diary for ≥2 menstrual cycles.
  • Management: Lifestyle, SSRIs (1st line for PMDD), OCPs (Drospirenone-containing).

  ⭐ Acanthosis nigricans is a common cutaneous marker of insulin resistance in PCOS.

High‑Yield Points - ⚡ Biggest Takeaways

• Primary amenorrhea: No menses by 15 yrs (normal development) or 13 yrs (no secondary sex characteristics). Mullerian agenesis is a key cause.
• Secondary amenorrhea: Menses cessation for >3-6 months. Pregnancy is the #1 cause.
• Adolescent AUB: Usually anovulatory due to immature HPO axis. Rule out pregnancy.
• PCOS: Key cause of oligomenorrhea & hyperandrogenism. Use Rotterdam criteria.
• Primary dysmenorrhea: Due to excess prostaglandins. NSAIDs are first-line.
• Turner Syndrome (45,XO): Consider in primary amenorrhea with gonadal dysgenesis and short stature.
• Anorexia nervosa: Can cause functional hypothalamic amenorrhea; screen in adolescents with amenorrhea and low BMI.