5 Common Reasons for a Late Period

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Late or missed periods can also be the result of more complicated or serious medical conditions. Polycystic ovarian syndrome (an imbalance in female sex hormones such as estrogen and progesterone), thyroid disease, pituitary disease, a pituitary tumor, sexually transmitted diseases, infections, perimenopause and menopause have all been linked to menstrual cycle irregularities.

In rare cases, diseases such as diabetes, liver ailments and irritable bowel syndrome can delay or prevent menstruation. Furthermore, medications, including some birth control methods and antidepressants, can also result in lighter, less frequent or missed periods.

For women who recently stopped using birth control, their bodies may take as long as three months to acclimate and resume normal cycles.

So, in short, if you have questions about why you've missed your period and you've ruled out pregnancy, don't worry unnecessarily. Take the next step and consult your medical professional to determine the underlying cause.

We have lots more information about missed periods below.

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  • 34 Menopause Symptoms. "Menstrual Irregularities." 2010. (March 24, 2011)http://www.34-menopause-symptoms.com/irregular-periods/articles/menstrual-irregularities.htm
  • American Pregnancy Association. "Taking a Pregnancy Test." February 2011. (April 11, 2011).http://www.americanpregnancy.org/gettingpregnant/takingapregnancytest.html
  • Centers for Disease Control and Prevention. "Healthy Weight -- it's not a diet, it's a lifestyle!" Feb. 15, 2011. (March 30, 2011)http://www.cdc.gov/healthyweight/assessing/bmi/index.html
  • Chandran, Latha. "Menstruation Disorders." WebMD. June 10, 2009 (March 25, 2011)http://emedicine.medscape.com/article/953945-overview
  • Epigee. "Menstrual Cycle Disturbances: Why is My Period Late?" (March 30, 2011)http://www.epigee.org/health/lateperiod.html Feminist Women's Health Center. "Menstrual Cycles: What Really Happens in those 28 Days?!" Jan. 21, 2011. (March 30, 2011) http://www.fwhc.org/health/moon.htm
  • MedlinePlus. "Menstrual Periods -- heavy, prolonged, or irregular." Sept. 2, 2009 (March 21, 2011)http://www.nlm.nih.gov/medlineplus/ency/article/003263.htm
  • MedlinePlus. "Menstruation." National Library of Medicine; National Institutes of Health. (March 21, 2011)http://www.nlm.nih.gov/medlineplus/menstruation.html
  • MedlinePlus. "Menstruation -- absent." National Library of Medicine; National Institutes of Health. June 16, 2010. (March 30, 2011)http://www.nlm.nih.gov/medlineplus/ency/article/003149.htm
  • National Institute of Child Health & Human Development. "Amenorrhea." May 14, 2007. (March 23, 2011)http://www.nichd.nih.gov/health/topics/amenorrhea.cfm
  • National Institute of Child Health & Human Development. "Menstrual Irregularities." May 24, 2007. (March 23, 2011)http://www.nichd.nih.gov/health/topics/Menstrual_Irregularities.cfm
  • National Institute of Child Health & Human Development. "Menstruation and the Menstrual Cycle." Sept. 10, 2006. (March 23, 2011)http://www.nichd.nih.gov/health/topics/menstruation_and_the_menstrual_cycle.cfm
  • National Institutes of Health. "Prior Stress Could Worsen Premenstrual Symptoms, NIH Study Finds." Aug. 23, 2010 (March 22, 2011)http://www.nichd.nih.gov/news/releases/082310-prior-stress-worsen-premenstrual-symptoms.cfm?from=women
  • U.S. Department of Health and Human Services, Office on Women's Health. "Menstruation and the Menstrual Cycle." Oct. 21, 2009 (March 22, 2011)http://www.womenshealth.gov/faq/menstruation.pdf
  • Volk, Elzi. "Female Athletes and Menstrual Irregularities." Think Muscle. 2010. (March 25, 2011)http://www.thinkmuscle.com/articles/volk/menstrual-cycle.htm
  • WebMD. "Missed or Irregular Periods." July 2, 2009. (March 30, 2010)http://women.webmd.com/tc/missed-or-irregular-periods-topic-overview


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