You always seem to know your period is on the way when you feel emotional and bloated, and suddenly develop a craving for something salty or sweet. It comes around every month, almost like clockwork, and although the discharge of blood and mucosal tissue may be inconvenient, it plays a vital role in the body's reproductive system. And there are also many interesting things to know about your period.

Pregnancy and periods are linked

The menstrual cycle is designed to get a person pregnant, and when no egg is fertilized during that month the uterus sheds its lining, which is when you get a period. Most periods last between three to seven days, Teen Vogue reports.

The blood can be different colors

A person may notice that their period blood is sometimes a more brownish color, but this is nothing to worry about. Buzzfeed spoke with Dr. Lauren Streicher, who revealed that while red blood indicates active bleeding, brown blood just means it’s been in the vagina longer.

Your voice changes during your period

People having periods may not notice a change in their voice, but the reproduction hormones reportedly have an effect on vocalization.

Almost every woman ruins her underwear

Stains on your underwear during your period are totally normal, and according to Cosmopolitan, 54 percent of 36,000 women surveyed for THINX, revealed they had stained their underwear.

A woman spends a lot of time on her period

The added amount of time of your period adds up to ten years, according to the company DAME, Marie Claire reports. The average person with a menstrual cycle also uses between 11,000 and 15,000 sanitary products in her life.

Your period can worsen asthma

Cosmopolitan reveals that a study published in the Journal of Multidisciplinary Respiratory Medicine found that in the week ahead of a period, people had an increased sensitivity to allergens.

A rare disorder can cause bleeding from the eyes

Don’t worry, it’s highly unlikely that this will happen, but according to Cosmopolitan, vicarious menstruation can cause you to bleed from other organs instead of your uterus (including your eyes) while you are on your period. Terrifying, but extremely rare.

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