These include fibroids or "lumps" in the uterus, cancer, and heavy or irregular periods.

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As you mentioned, all of these issues--acne, stopping the pill and irregular periods -- may certainly be related.

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Endocrine disorders like thyroid disease can cause irregular periods, too, as can polycystic ovary disease, a hormonal glitch that may lead to obesity, acne, and excessive hair growth.

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What's the most likely cause of my irregular periods?

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Irregular periods -- maybe yours used to come every 28 days but is now arriving on day 21, 35, 28, and back to 21 again -- can be a symptom of perimenopause.

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Irregular periods aren't the only problems.

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Two years after her wedding and still not pregnant, the 26-year-old visited a gynecologist, who diagnosed her with polycystic ovary syndrome, an endocrine disorder that can cause women to stop ovulating, gain unusual weight, develop irregular periods or skin problems and grow abnormal facial and body hair.

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They can cause irregular spotting between periods or they may be asymptomatic.

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