To evaluate this factor as objectively as possible, we had to figure out a way to simulate a vagina.

We recommend starting with a medium-firm cup and figuring things out from there, but if you’re an athlete or really into Kegel exercises, you might want a firmer cup.We tested a handful of firmness, handle, and size combinations, and they were all easy to insert and remove because we could fold them in all sorts of ways thanks to their hitting the sweet spot of firmness and thickness.

Overall, cup evangelists say that it’s worth a few messes, and that anybody who is considering switching from pads and tampons should stick with a cup for at least four cycles before giving up. Our overall favorite is the Saalt Disc, but the Flex Reusable Disc is also worth considering, especially if you have a heavy flow. The team is evaluating the number of study participants who experience IUD displacement—in which the device shifts more than 1 cm from its original position in the uterus—when they use manufacturer-recommended cup insertion and removal techniques. This setup simulated the stretchiness of the vagina pretty well, but the water moved around enough inside the bags that I could never get the cups in and out without incident. Discs have a much higher capacity than cups do—the average menstrual disc in our test group has a capacity of about 45 milliliters, whereas most “small” menstrual cups hold only about 25 mL and, according to Put A Cup In It, the largest menstrual cup available holds 51 mL.Discontinue use and contact a medical practitioner if you experience any pain or discomfort while using the Lily Cup. Keep your cup clean with Intimate Accessory Cleaner in-between uses, and wash your cups discreetly in Sterilizing Cup - wherever you are. Some menstrual cup makers and advocates also claim that using a cup eliminates the risk of toxic shock syndrome. It may take a while to get used to inserting and removing a cup or disc, and even for pros, using one involves handling your menses more than you do with pads, tampons, and some period underwear.

Perhaps the cup itself is generating suction, and when a user removes the cup, that suction pulls the IUD down and out. It does have a hollow stem, which can collect blood and other tissue more easily than solid stems, making this cup a bit more difficult to clean than our other picks. Menstrual cup reviewer Jackie Bolen said that her biggest frustration with menstrual cups is that “people give up too soon.So if you’ve tried a DivaCup and found it uncomfortable, but you still like the idea of a menstrual cup, we encourage you to try again with a smaller cup. If you're looking for an everyday, reliable period solution, Lily Cup™ Compact will be your best bet.

Plus, since it is a non-absorbent product it reduces the risk of Toxic Shock Syndrome which can occur with disposable tampons if they are not changed regularly enough.

Then I tried a DIY masturbator that involved either one bag of water or several bags of water tied together. For this test, we used pig blood mixed with egg whites to get as close to the consistency and staining power of actual menstrual fluid as possible.