Unfortunately, I have been unable to locate anything to link sex to missing a period except in the case of pregnancy.
There are a couple of other possibilities however. You haven't stated how old you are or how long you have had your period now. If you have not had it long, it may just be that your cycle is irregular and this means that regardless of whether or not you have sex, you may get your period more often or less often from time to time.
The other possibility is the presence of external factors. For example stress, medication, diet and so on can effect your menstrual cycle. Stress can be a major cause of irregular periods and medication in most cases can delay your period.
It is unlikely that having sex and missing a period are related to each other. However, I always recommend that if you have any concerns that might not have been explained in what I have said, you visit your doctor. You can speak to a female doctor or nurse if you wish but any concerns of this nature should be addressed with your doctor, who can investigate the matter further should he feel there is a problem. [ Vikki27's advice column | Ask Vikki27 A Question ]
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