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"Why would my period be one week late last month, and one week early this month?"

ZocdocAnswersWhy would my period be one week late last month, and one week early this month?


I am 42. Nothing else unusual


Thank you for your question. There are many different possible explanations for changes in the duration of the menstrual cycle and the best thing to do is to discuss this with your doctor. This cycle can be very sensitive to many things, including environmental factors, stress, exercise level, overall health, sleep, and many other things. Additionally, your age may be part of the explanation, as there is a time point where the female menstrual cycle will begin to alter and eventually cease during menopause. While 42 may seem young, your family history and your overall health may again offer some information about what is causing these changes. All told, there are many reasons that the length of your cycle could be different. While many of these are quite common, others could represent significant risks to your overall health and should be discussed with your physician. As with any such change, please speak with your doctor about your question. Your OB/GYN would likely be able to help best, and alternatively your primary care doctor (which may be the same person) would be able to explain and help you know if there is more that needs to be done at this time. Please speak with your doctor.

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