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A 23-year-old female asked:

Period used to come on 29-31 day. in dec took planb. period is irregular now. since march cycle lenght is 32-33-28-28-30-26-26. is there a problem? :(

1 doctor answer1 doctor weighed in
Dr. Jeff Livingston
Obstetrics and Gynecology 24 years experience
You are regular: Slight variation from month to month is expected. Plan B stays in your system for about 12-18 hours so the effects are long gone. A cycle every 21-35 days is considered normal. You are within that window. If you would like even better cycle control then start birth control.
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Last updated Aug 31, 2014


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