We like to think that, no matter how light and short or long and disastrously heavy our periods are, they at least follow a familiar pattern. It can be quite disconcerting then, when our previously steady cycles deviate significantly from the norm. To put your mind at ease, here are the basics of heavy bleeding, including when it is and isn’t a big deal.
First, What Constitutes ‘Heavy’?
The average period will see about 30-40 mL ( 1- 1.35 fluid oz ) of blood loss with a normal upper limit of 80 mL (2.7 fluid oz). If you’re using a Lily Cup Classic A, for example, you’d probably fill it completely less than 3 times over the course of your period. Menstrual cups make it very easy to monitor the amount of flow you have but ‘heavy’ can also be indicated by:
- Needing to change your pad or tampon at least every hour for a day or more
- Needing to change your pad in the middle or the night or double up
- Pass blood clots larger than an American quarter
Heavy periods are more common in our teens or right before menopause, or, again, always be heavy throughout your life. It’s called menorrhagia, and if it’s a sudden shift (or you are anemic) this may be something to discuss with your doctor.
Main Causes of Menorrhagia
1.You Just Switched Up Your Birth Control
If you’ve just switched to the mini-pills (the ones that are progestogen-only as opposed to combination) or are coming off oral contraceptives entirely, chances are you will notice a heavier flow. The patch is also associated with lighter periods, so discontinuing use of it will cause your flow to get heavier.
When it comes to IUDs, while Mirena is associated with lighter periods, non-hormonal copper IUDs actually cause heavier bleeding in many women, though this should discontinue about 3 months after insertion—definitely go see your doctor if it doesn’t.
2.You’re Pre Menopausal
Yep, this wondrous 8-10 month period leading up to menopause—known as perimenopause—can affect women as young as 30, so don’t rule it out as the cause of suddenly heavier bleeding, especially if there is a history of early menopause in your family.
3.You’re Taking Blood Thinners
Have you ever gone to get your ear pierced and forgotten to mention to the piercer that you took some Advil for pain? You (and your poor piercer) probably encountered a LOT more blood than they were banking on.
It doesn’t always click—and we aren’t always warned—of all the ways that new medication will impact our bodies, so you may have not realized that anticoagulants will indeed cause a heavier period than normal. Anticoagulants and other anti-inflammatories prevent clots so that blood can flow more easily through your body… which includes, you guessed it—your period.
4.You Have Uterine Fibroids
While it might sound serious, uterine fibroids are actually benign growths that are caused by high levels of estrogen. They will happen to about a third of fertile women, and pass on their own without treatment. Unfortunately, they do come with side effects—painful cramping and heavier periods.
5.You Have Polycystic Ovary Syndrome (PCOS)
Affecting between 8-20% of women worldwide, PCOS is a condition where many small cysts cover the ovaries. This causes ovulation, and periods, to be irregular, and milder cases can mean that hormone imbalance within the body causes extra-thick uterine lining and thus heavier periods when they do come.
6.You Have an Infection
Any infection of the uterine lining can cause heavier bleeding—yes, this includes STIs like gonorrhea and chlamydia. These types of infection cause pelvic inflammatory disease, which can be a major cause of infertility. If you have had unprotected sex—penetrative or oral—and notice heavier bleeding, it’s important to get yourself tested and given treatment.