How a Cervical Cap Works

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A cervical cap is a reusable, hormone-free, silicone cup that's inserted into the vagina up to six hours before sex to prevent pregnancy. Also known as FemCap (or the cap, cervical barrier, the shield, or Lea's Shield) this is a safe, convenient, and effective birth control method. One cervical cap can last for up to two years.

Cervical caps are a type of barrier birth control. The cervical cap is similar to a diaphragm — both a diaphragm and a cervical cap prevent sperm from reaching and fertilizing an egg. But unlike a diaphragm, a cervical cap is much smaller.

Young woman holding birth control pills
PhotoAlto / Ale Ventura / PhotoAlto Agency RF Collections / Getty Images

How to Use

After some practice, cervical caps are easy to use. You insert the cervical cap into your vagina and make sure that it fits closely over your cervix. The cervical cap will keep sperm from entering your uterus by forming a secure seal around your cervix. For added protection, you should also be using spermicide along with your cervical cap.

You can insert your cervical cap before having sex (you can actually insert your cervical cap up to six hours before you plan to have sex). After having sex, you should wait at least 6 hours before removing — do not leave your cervical cap in place for more than 48 hours. You do not need to take out your cervical cap if you plan on having sex again. All you have to do is add more spermicide way down deep in your vagina.

Pros and Cons

You may love the idea of a cervical cap because:

  • It is discreet and can easily be carried in your pocket or purse
  • It is effective immediately and completely reversible
  • Neither you nor your partner will typically feel your cervical cap
  • It does not interrupt sex (since you can insert it ahead of time)
  • Cervical caps do not affect your natural hormones (they are hormone-free), so they can also be used by breastfeeding mommies

Possible drawbacks include:

  • You can't use your cervical cap when you are having a period
  • It may be pushed out of place by some penis sizes, heavy thrusting during sex, and certain sexual positions
  • You may find it difficult to insert your cervical cap
  • You have to make sure that your cervical cap is in the proper place every time you have sex


Just follow these instructions and you'll have your cervical cap inserted in a breeze! (Here's a quick tip: it is much easier to insert your cervical cap before you become sexually aroused.)

  1. Wash your hands (don't forget the soap).
  2. Put about a pea-sized amount of spermicide in the dome of your cervical cap. Then spread a thin layer around the edge. Put another pea-sized amount of spermicide in the folded area between the dome and the edge.
  3. Find a comfortable position (lie down, stand with one foot on a chair, squat, or sit on the edge of a chair).
  4. Insert your index and middle fingers into your vagina, so you can find your cervix. Doing this will help you to determine where to place your cervical cap.
  5. Squeeze the rim of your cervical cap together with one hand and then separate your labia with your other hand. Insert the cervical cap (dome-side down) into your vagina, with the long edge going in first.
  6. Push your cervical cap down towards your tush and then up and onto your cervix.


Taking out your cervical cap is as easy as one, two, three (just make sure it's been at least six hours since you had sex).

  1. Again, wash your hands with soap!
  2. Squat down, grab the removal strap, and rotate your cervical cap.
  3. Push on the cervical cap's dome with your finger (this breaks the suction). Then use your finger to hook it under the removal strap and pull out your cervical cap.


After removing your cervical cap, it should be washed, rinsed with warm water, dried, and stored in its case. Make sure to do this each time you use it. You should not use oil-based lubricants (like petroleum jelly or baby oil) with your cervical cap because these substances may damage it.

Also, it is a good idea to examine your cervical cap regularly. You can do this by looking for small holes or weak spots — holding your cervical cap up to the light or fill it with water (and look for leaks). Your cervical cap can still be used if it has become discolored, but should not be used if you notice any holes or weakened areas (to be on the safe side, use a back-up birth control method). As long as you take proper care of your cervical cap, it should last you for about two years.

How to Obtain One

You have to go to your healthcare provider to get a cervical cap. Why? A cervical cap is considered to be a prescription birth control method.

At your appointment, your healthcare provider will examine you and make sure that you are a good candidate for a cervical cap. If so, your healthcare provider will then determine which size cervical cap will best fit your body. Make sure to ask for information about how to properly use your cervical cap. Your healthcare provider will then give you a prescription, so you can pick up your new cervical cap.

FemCap Sizes

FemCap comes in three sizes:

  • Small: Used if you have never been pregnant.
  • Medium: Used if you have ever had a cesarean section delivery or abortion.
  • Large: Used if you have ever had a vaginal birth.


Once you have your cervical cap prescription, you can buy it at your local pharmacy. Costs include the price for your healthcare provider's exam (can range up to $250), the price of your cervical cap (can cost up to $100), and the price of spermicide (may cost up to $25).


If you have never given birth, the cervical cap is:

  • 84 percent effective with typical use
  • 91 percent effective with perfect use

Of every 100 people who use cervical caps for one year, for those who have not given birth, 16 will become pregnant (with typical use) and 9 will become pregnant with perfect use.

If you have given birth, the cervical cap is:

  • 68 percent effective with typical use
  • 74 percent effective with perfect use

Of every 100 people who use cervical caps for one year, for those who have given birth, 32 will become pregnant (with typical use) and 26 will become pregnant with perfect use.

To increase the effectiveness of your cervical cap, make sure to practice inserting and removing your cervical cap before actually using it during sex. The highest risk of pregnancy occurs during the first few months of use. Also, check the position of your cervical cap before and after sex to make sure that it has stayed in place. If your cap has moved during sex, you may want to consider using emergency contraception.

Currently Available

Right now, FemCap is the only available cervical cap in the United States.

Lea's Shield is a silicone cup with an air valve and a loop to remove and comes in one size. It was FDA-approved in 2002 but is no longer being offered in the U.S.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  • Koeniger-Donohue R. "The FemCap." Advanced Health Assessment of Women: Clinical Skills and Procedures. Springer Publishing Company; 2014: 379-386.
  • Nelson AL, Russo J. "Barrier contraceptives." In: The Handbook of Contraception. Springer Nature; 2016:181–202.

By Dawn Stacey, PhD, LMHC
Dawn Stacey, PhD, LMHC, is a published author, college professor, and mental health consultant with over 15 years of counseling experience.