Differential Diagnosis for Prolonged Menstruation

The patient's first menstruation cycle lasting 2 weeks can be caused by various factors. Here's a differential diagnosis, categorized for clarity:

• Single Most Likely Diagnosis
  • Anovulatory bleeding: This is a common cause of irregular and prolonged menstrual bleeding, especially during the first few years after menarche. The body may take time to establish a regular menstrual cycle, leading to anovulatory bleeding.
• Other Likely Diagnoses
  • Immature hypothalamic-pituitary-ovarian axis: The hormonal regulation of the menstrual cycle may not be fully developed, leading to irregular and prolonged bleeding.
  • Hormonal imbalance: Fluctuations in estrogen and progesterone levels can cause irregular menstrual bleeding.
  • Uterine or cervical anomalies: Congenital anomalies, such as a septate uterus or cervical stenosis, can lead to abnormal menstrual bleeding.
• Do Not Miss Diagnoses
  • Bleeding disorders (e.g., von Willebrand disease): These conditions can cause heavy and prolonged menstrual bleeding, and it's crucial to diagnose them to provide appropriate management.
  • Thyroid disorders: Hypothyroidism or hyperthyroidism can affect menstrual regularity and duration.
  • Pregnancy complications: Although unlikely in a patient experiencing their first menstruation, it's essential to rule out ectopic pregnancy or other pregnancy-related complications.
• Rare Diagnoses
  • Androgen insensitivity syndrome: A rare genetic disorder that can cause irregular menstrual bleeding.
  • Polycystic ovary syndrome (PCOS): Although PCOS is a common endocrine disorder, it's less likely to be the primary cause of prolonged menstrual bleeding in a patient experiencing their first menstruation.
  • Other rare bleeding disorders (e.g., factor XI deficiency): These conditions can cause heavy and prolonged menstrual bleeding, but they are relatively rare.