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Merula OS Menstrual Cup

Merula OS Menstrual Cup

Regular price $35.99 USD
Regular price Sale price $35.99 USD
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The Merula OS (One Size) menstrual cup is a low profile cup ideal for those with a low cervix and especially those with a low cervix and a heavy flow. It has a capacity of 38 ml,  which is roughly equal to two large tampons, and is comparable to longer bullet shaped cups. The unique ladder stem can be trimmed by the rungs for a comfortable and custom fit.

From weak to strong pelvic floor muscles, the Merula Cup stays where it belongs. It can be worn in a folded up state and does not have to open completely, even strong pelvic floor muscles do not make it lose its shape.

Merula OS cups come in many fun colors and include a coordinating fashion pouch in each box. 

Merula Cup Benefits

  • It has a very large capacity (up to 38 ml / 1.285 fl oz). With a diameter from 40 mm to 46 mm / 1.575 in. to 1.811 in.
  • Due to its spherical shape, Merula Cup has a short height of only 39 mm / 1.535 in. and an impressive capacity
  • The Merula Cup can easily be used by those with a low cervix. The cup can also be used without any difficulty if you have a high cervix, as it has a long, ladder-shaped stem

Your purchase includes: One Merula OS Cup, one coordinating fashion fabric pouch, and user instructions.

Manufacturing and Standards The Merula Cup is made of certified medical grade silicone without chemical additives like plasticizers and is vegan friendly. The Merula Cup strawberry (pink) was awarded the overall rating of “VERY GOOD” by the specialist magazine “ÖKO-TEST” in the 04/2020 issue. A total of 15 menstrual cups were tested in three categories for their ingredients, resilience and other defects: The Merula Cup strawberry (pink) also received the top grade “VERY GOOD” in all three categories without any defects or comments.

Merula Cup Sizing Guide and Size Chart

Merula Cup is a One Size option, due to the unique shape most people can use this size cup. The long ladder stem and short body mean the Merula Cup works for people with any length cervix - simply trim the stem to the length that is best. The high capacity of this cup and short body make it the best option for those with a heavy period and a low cervix.



Merula Cup OS measurement dimensions
Merula OS Cup Size Chart
Merula OS
Length Diameter Volume
39mm 46mm 38ml

Measurements do not include stem length, which adds 33 mm to the total cup length. Can be trimmed at each rung.

HSA/FSA Eligible

This product is eligible for purchase using your HSA/FSA card or for reimbursement with your HSA/FSA plan under the CARES Act. See our FAQ for more on how to purchase your menstrual products with HSA/FSA.

Why Buy From Period.Shop?

Unlike big box stores and huge billion-dollar websites, Period.Shop carefully hand selects and vets each and every product we carry to make sure they meet our strict standards. If you find it on Period.Shop you can trust the product is ethically made, high-quality, and a proprietary design. Only brands who meet at least one of our standards will be carried by Period.Shop, but most brands meet multiple or even all three. Our warehouse is located in South Carolina and all products are shipped by us with the exception of Saalt Wear items, shipped directly to our customers by Saalt.

Kim Rosas, the founder of Period.Shop and Period Nirvana, has spent the last 12+ years in the reusable products space. After many years of creating educational content and teaching workshops around the country, she started the first reusable menstrual products store in the US and an educational platform for reusables: Period Nirvana. The mission was simple - provide the highest quality shopping experience and resources to make finding the perfect menstrual cup or disc easier. As a leading expert in this space, there is no one more qualified to curate your products than Kim Rosas. By shopping with Period.Shop you can support a small business that is providing free educational resources. Plus, you know you’re purchasing a product that has the Period.Shop stamp of approval.

Return Policy

Return and Refund Policy ---- Due to the nature of our products, Period.Shop cannot accept any product returns nor accept product exchanges or offer refunds. This includes on items that were never opened. 

We can replace items if they are defective or damaged at arrival. We can replace items if you were sent the wrong product, wrong product size, or wrong product color than the product you ordered.

Replacement requests for defective or damaged at arrival products are considered and reviewed on a case by case basis, and are at the sole discretion of Period.Shop and its owners. If you are in need of a product replacement, we ask that you send visual proof and supporting evidence to our email at We will evaluate your request in a timely manner but be aware that we do not answer emails on weekends or holidays. Depending on where you live, the time it may take for your replaced product to reach you may vary.

Each brand uses different packaging methods, some brands have security seals on their packaging while others do not. All items carried and sold by Period.Shop come to us directly from the manufacturer or distributor.

Order Changes or Cancelations - Please review your sizes and address carefully!

Period.Shop ships every weekday, often within hours of the order being placed. For that reason not all order changes or cancelations can be honored. If you reach out after noticing a mistake you made during your order and it has already been shipped we are not able to send a replacement for you. Please know that we do our best to make changes or cancelations when we receive the request but it's not always possible. We check emails and messages each weekday beginning at around 9-10 am based on availability. We begin shipping orders as early as 7 am on weekdays. Emails and messages received over the weekend or holidays are addressed on the next workday. To reach Period.Shop about order questions please email Your message may not be seen if you send it to our social accounts.


Contact for any issues with your order or questions about refunds or replacements.

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