How does a menstrual cup work? It is a bit of a mystery. After all, we can’t see what’s happening inside our own bodies.
Understandably you might have questions.“Where does it go?” “Why doesn’t it leak?” How do you pee with a menstrual cup in?”
This video will show how a menstrual cup actually works and I’ve also included how menstrual discs work. It’s truly everything you need to know. And the below illustrations will allow you to see “inside your body”. The simple anatomy explanations will help you finally answer the question “How does a menstrual cup work?”
Watch: Inside Your Body A Guide to Your Menstrual Cup and Anatomy
To start: You have three holes down there!
The menstrual cup or disc is inserted into the vagina until it sits below the cervix, where menstrual blood flows out during your period. The menstrual cup makes contact inside your vaginal canal 360° to create a leakproof seal. The pelvic muscles in the vagina are what keep the cup inside your body during wear. If you’re wearing a menstrual disc, these work slightly differently and are kept in place by the pubic bone (discussed further down.)
Reproductive Anatomy to Know for Menstrual Cup Use
The Cervix
The lower part of the uterus (the neck) with an opening that allows menstrual fluid to be released for each period. The cervix moves position throughout the cycle and can change how high or low it is in relation to your vaginal opening.
Contrary to some advice, the menstrual cup is not designed to suction to and cover the cervix. It can happen for some people and if it does that’s okay (if it’s comfortable for you), but this is not by design. The cervix is the ceiling of your vagina; a menstrual cup can’t go past it and “get lost” in your body.
Related Resource: How to measure your cervix height
The Uterus
A reproductive organ that builds uterine lining throughout the monthly menstrual cycle. If during your cycle an egg isn’t fertilized to produce a pregnancy the lining is shed. That lining is your period.
The Vaginal Canal
The internal “hallway” that connects your cervix to your external vulva. This passage allows for your period to exit your body and is also where your menstrual cup will sit inside.
The Pelvic Floor
A network of muscles that functions like a hammock, tasked with holding up your uterus, bladder, and rectum. These muscles extend from the front of the pelvis to the coccyx (tailbone.) A very strong pelvic floor may push a menstrual cup down during wear, so a firmer cup or a menstrual disc may be best. If you have a weak or average pelvic floor a softer or average menstrual cup is likely best.
The Bladder
Situated in front of the vaginal canal, the bladder stores urine before it’s released by the urethra and exits the body. In some cases a menstrual cup can apply pressure to the bladder because of the placement which can make the wearer feel the urge to urinate.
The Urethra
The exit passage for urine leaving the body. In some cases a menstrual cup can apply pressure to the urethra that makes urine leave the body slower. In rarer cases a cup can apply enough pressure to restrict/block urine from exiting.
The Rectum
The bottom portion of the large intestines and “last stop” for feces before it’s released by the sphincter through the anus. In some cases a menstrual cup can apply pressure to the rectal area. In rarer cases the cup makes defecating harder to accomplish.
The Sphincter
The muscles that control the bowel and release feces through the anus. The bowel muscles are part of the network of pelvic floor muscles. During bowel movements you might push your cup down lower or even out of the body completely. Be careful!
Vaginal Fornix
The area around the cervix in the upper vagina – there is an anterior vaginal fornix space in front of the cervix and posterior vaginal fornix behind the cervix. A menstrual disc is worn in this “tented” more spacious area of the vagina.
The Pubic Bone
An anterior (front facing) bone in the pelvis. When wearing a menstrual disc you position and prop the disc against the pubic bone to keep it in place.
The Clitoris
Unaffected by a menstrual cup, but important to know in relation to placement in the vulva. The clitoris is located above the urethra. The urethral opening is above the vagina. The vaginal opening is above the anus.
Together these parts of your body are all affected by or directly influence where and how your menstrual cup is worn. When you see the entire picture many things will make more sense when it comes to inserting your menstrual cup, or why your menstrual cup gets pushed down during a bowel movement. Seeing “inside your body” for how a menstrual cup works also helps you understand why a cup still allows you to urinate while wearing it.
More Resources:
The Vulva Gallery: Amazing illustrations showcasing the beautiful diversity of vulvas, anatomical diagrams.
Alicia, Pelvic PT: A Tiktok account dedicated to all things pelvic floor health. Start with this video and run through the series.
Dr. Jen Gunter: Known as Twitter’s resident gynocologist, Dr. Jen is also the author of The Vagina Bible. Her TEDx Talk on periods is a must watch.
Dr. Heather Irobunda: Tiktok and Instagram OB/GYN from Brooklyn. Dr. Heather tackles many health topics in her education and fun videos.
Would love to know where this anatomy model is from. It’s amazing!
I made part of it and the other parts are from an old nuvaring model