The odor of menstruation does not have to smell bad. It's true you can have a characteristic odor and in some cases stronger. If the odor smells bad it is for some reason ... In addition, the response to odors is personal. A smell that can please one person to another may dislike. Or the reverse.
But keep in mind that although you can reduce menstrual odor is impossible to stop to smell good. We should note that menstrual blood is a mixture consisting of blood, dead cells (the endometrium of the uterus), some mucus and mucilaginous substances. And all these substances accumulated during nearly a month can produce a strong odor. Normal is not?
Possibly one of the main reasons that the rule does smell worse the infection. Basically occurs when either fungal infection or some type of bacteria (mainly Escherichia coli famous but there are others such as Gardnerella vaginalis). Usually these types of infections were caused by a change in pH of the skin, a drop of defenses or poor hygiene.
Another cause is the spotting, little bleeding, usually darker brownish, which occur due to loss of blood clots that typically form during menstruation. Find out more here's the link.
The smell of the rule head brings many women who suffer if you sense that they smell bad periods and are uncomfortable.