Irregular Periods Explained: The Main Reasons Why Your Period Is Out of Whack

Pregnancy

Pregnancy is the most obvious reason as to why a regular menstrual cycle comes to a halt. A menstrual period occurs when a prepared uterine lining fails to embed a fertilized egg. When the fertilized egg succeeds at becoming implanted in the lining and continues to grow into a baby, a woman does not continue to shed her uterine lining. Therefore, stopping the menstrual cycle for the duration of her pregnancy, and in some cases longer if the woman is breastfeeding. If bleeding does occur during pregnancy, it is not normal and requires immediate attention from a health care provider.

Medication

Taking prescription or over-the-counter medication can also cause a menstrual period to occur later than normal. This happens mainly because many over-the-counter drugs can change the way the body produces the hormones estrogen and progesterone. Many medications can affect your menstrual cycle; these include anything from your standard aspirin to prescribed thyroid medication.