Irregular and Absent Periods

Understanding Changes in Your Cycle
Irregular periods may arrive unpredictably, occur less often, or become more frequent than usual. Absent periods, known as amenorrhea, mean menstruation has not started or has stopped.
A change in your cycle is a symptom rather than a diagnosis. Understanding the cause helps determine what kind of care is appropriate.
What Can Cause Irregular or Absent Periods?
Menstrual cycles depend on communication between the brain, ovaries, and uterus. Several factors can affect this process, including:
Pregnancy, breastfeeding, or menopause
PCOS
Thyroid conditions or elevated prolactin
Insufficient nutrition or intensive exercise
Significant stress or changes in weight
Perimenopause or primary ovarian insufficiency
Hormonal contraception and certain medications