To Catch a Cheater.

A disposable tampon for women with a safe chemical element and or micro chip that detects from a significant other's semen or saliva the presence of 'other than' hormones, DNA or foreign fluid that can only be attributed to intercourse with another person.

The suspicious party would insert the tampon to gather evidence, then compare the results to a chart to detect the presence of other DNA, or multiple DNA.
Of course, a baseline would have to be established by using the tampon to establish a baseline.

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