Irregular periods, meaning the time between periods varies a lot, or periods are skipped occasionally, are extremely common in the first one to two years after menarche, while your hormone signals are still finding their rhythm.
Common, Non-Worrying Causes
- Being in the first couple of years after your first period.
- Stress, travel, or big changes in routine.
- Significant changes in weight, exercise level, or sleep.
- Illness.
When to Check In With a Doctor
- No period at all for more than 3 months after your cycle had already become regular.
- No period by age 15.
- Periods that are consistently less than 21 or more than 45 days apart after the first couple of years.
As covered in Chapter 8, most irregularity in the early years resolves on its own. A doctor's visit is about ruling out and addressing causes, not assuming something is wrong.