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The production of sex hormones increases at puberty to a level that will generally remain constant for the duration of a woman's reproductive life. Pubescent women thus experience the onset of the menstrual cycle. This increase of sex hormones triggers the dilation of small blood vessels in the gums which is seen as an increase in redness, gingival bleeding, and swelling.

In addition, microbial changes have been reported where there is a shift from a "healthy" microbial flora to a more "destructive" or pathogenic microbial flora. This change has been attributed to the increased levels of hormones in the blood, which certain pathogenic bacteria can use for growth and proliferation.

The presence of plaque and calculus (tartar) on the teeth can exacerbate this response. This underscores the importance of good oral hygiene habits learned at an early age, combined with periodic dental visits and cleanings. The tendency for inflammation and swelling associated with puberty appears to decrease as a young woman gets older.

However, women may occasionally experience what is often termed menstruation gingivitis just prior to the onset of their period. Red, swollen, tender gums that bleed easily and the presence of mouth sores are common. Menstruation gingivitis tends to disappear once a woman's period has begun, however, inadequate oral hygiene can increase its severity and level of discomfort.