Late or Missed Period: Common Causes and When to Seek Evaluation

A period is considered late if it hasn't started 5+ days after the expected date. A missed period is no bleeding for 6+ weeks.

Common Causes (Non-Pregnancy)

• Stress: Cortisol disrupts hypothalamic-pituitary-ovarian axis.
• Weight changes: Significant loss/gain, low body fat, eating disorders.
• Excessive exercise: Energy deficit suppresses ovulation.
• Hormonal imbalances: PCOS, thyroid disorders (hypo/hyperthyroidism), hyperprolactinemia.
• Medications: Hormonal contraceptives (especially starting/stopping), antipsychotics, chemotherapy, steroids.
• Perimenopause: Irregular cycles in 40s–50s.
• Chronic illness: Diabetes, celiac disease, inflammatory bowel disease.

Pregnancy Testing Nuances

Home urine tests detect hCG. False negatives can occur if tested too early (before missed period), diluted urine, expired test, or ectopic pregnancy (low hCG rise). Blood tests (quantitative β-hCG) are more sensitive.

When to See a Clinician

• Negative test but period >1 week late.
• 2+ consecutive missed cycles.
• Associated symptoms: pelvic pain, abnormal discharge, hirsutism, acne, weight changes, hot flashes.
• Desire for fertility evaluation.