It's fairly common to experience irregular periods from time to time but absent periods (amenorrhea) should always be checked out.
7 Period Problems You Shouldn't Ignore
What causes menstrual irregularities?
Irregular Periods - Hormonal Imbalance Symptoms
Why Am I Spotting After My Period?
Everything You Need to Know About Irregular Periods
Period Won't Stop: Causes, Treatment, and More
Possible Causes of Abnormal Periods
Irregular Periods: Why Is My Period Late? - Penn Medicine
Can Sex Change Your Period? – Knix
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