From strange cravings, mood swings and erratic bowel movement, your periods can really throw a curveball at your body.

Of those that are rarely spoken about and still remains perplexing is the odor of your menstrual blood. While some describe the smell of menstrual blood as rusty or metallic, it is a combination of blood, tissue from the shedding of our uterine lining, vaginal secretions and a mix of organisms that are found inside our vagina.

Bottomline is, you never have to worry about the next person catching the odor.

So, if you’re still worried or concerned why your period blood smells different from regular blood, here is what you need to know about what is happening down there.

It’s supposed to smell

Yes, you heard that right. Blood itself has a certain smell and your period blood is no different. It is totally natural and it is not supposed to be completely odorless. The reason behind the ‘fishy’ smell is because your body is expelling vaginal mucus, bacteria, fluid and tissue.

Length of time

The odor of your menstrual fluid can be more or less intense depending on how long it sat in your uterus before being expelled. Speaking to Refinery29, Dr. Shirazian assistant professor in the Department of Obstetrics and Gynecology at NYU Langone Joan H. Tisch Center for Women's Health in NYC, noted that ‘’it’s either bacteria mixed with old blood or it’s bacteria in the vagina that’s coming out with the blood’’ that is the biggest factor in making your period blood’s scent “special and specific to you.’’

Moisture in the vagina

Another reason it could be smelling is due to moisture in the vagina which is totally normal. But if it has a strong fishy smell you may need to consult a doctor. This could a sign of bacterial vaginosis, an infection caused by germs when the pH of the vagina is out of balance.

Not changing your hygiene products frequently

One of the most common reasons of a smelly period could be out of not changing pads or tampons frequently enough. This is because the blood comes into contact with air and this gives a chance for bacteria to develop. When these bacteria ferment, this can cause an abnormal smell.

Excess blood

Excess blood in your vaginal area will cause some smell especially if you have a heavy flow. With more blood, more bacteria will grow so keeping the area as dry as possible is advised. It is also a good idea to wear cotton underwear and breathable clothes. According to Dr. Shirazian, many types of bacteria can grow during your period that are due to both blood and sweat.

Vigorously washing your vagina

While it is tempting to douche during your period, this extreme act could actually induce infections and thus make your vagina smell worse than before. You should never ever douche. According to Womenshealth.gov, douching can change the necessary balance of vaginal flora (bacteria that live in the vagina) and natural acidity in a healthy vagina. So, all you need to keep things down there clean is water. If you really must use soap, go for a natural one and only use on the outer parts of your vagina.