Contraceptive Diaphragm – single-size contraceptive barrier device

What is the single-size contraceptive barrier device (Caya®)?

The single-size contraceptive barrier device (Caya® diaphragm) is a new barrier method of contraception used by women.

Caya® is a silicone diaphragm which has been manufactured to have a more anatomical shape than traditional dome diaphragms. It has an oval contoured shape, flexible rim, grip dimples and a removal dome.

It is placed in the vagina so that it covers the cervix (entrance to the uterus) and tucks in behind the pubic bone. It is held in position by the pelvic muscles. Unlike traditional diaphragms, Caya® is available in one size only with this design estimated to fit approximately 80% of women. While the Caya® diaphragm can be purchased without the need for fitting, Family Planning Organisations recommend that where possible women are assessed by a health professional to make sure it fits correctly and to check that the device is inserted correctly to cover the cervix.

How does a diaphragm work?

When the male partner ejaculates inside the vagina during intercourse, the diaphragm is designed to prevent the sperm getting into the uterus. After intercourse the diaphragm must be left in place for a further six hours during which time any sperm in the vagina die (sperm in the vagina do not survive as long as sperm in the uterus or fallopian tubes due to the difference in the vaginal environment compared to the uterus or fallopian tubes). The manufacturer recommends use with a lactic-acid-containing lubricant gel.

How effective is the Caya® diaphragm?

As Caya® is a relatively new product there are very limited data available on how effective it is as a contraceptive. Data from clinical trials so far indicate that it is approximately between 82% and 86% effective. This means that between 14 and 18 out of every 100 women who use this method for a year may become pregnant when using the diaphragm.

The Caya® diaphragm, like all contraceptive diaphragms, is less effective than other methods of contraception including the contraceptive pill, implant and intrauterine methods.Which groups of women is the Caya® NOT suitable for?

  • Women who want a highly effective method of contraception and for whom an unintended pregnancy would be unacceptable
  • Women who have previously been fitted with a diaphragm which was either size 85 mm or larger or 60 mm or smaller. Caya® would be unlikely to be a good fit in these women.
  • Women who have given birth less than 6 weeks ago
  • Women with a history of a rare but serious condition called toxic shock syndrome
  • Women with certain types of vaginal prolapse (where the pelvic organs can drop down) or another anatomical reason that would make the diaphragm not cover the cervix correctly

Advantages as a contraceptive method

  • It provides an alternative for women who are unable to or choose not to use a hormonal method of contraception
  • It can be used by women and their partners who are allergic or sensitive to latex
  • It can be used on an intermittent basis when sexual activity occurs (it can be inserted well before the time of sexual activity if preferred)
  • It can be obtained without needing to visit a health professional

Disadvantages as a contraceptive method

  • It has a significantly lower effectiveness compared to other methods of contraception which may be unacceptable to some women
  • It does not protect against HIV and other STIs (sexually transmissible infections); it can however be used at the same time as a male or female condom for dual protection against STIs and pregnancy
  • It may be unacceptable to some women who do not feel comfortable inserting the device into the vagina

How to Use a Caya® Diaphragm

  1. Family Planning Organisations recommend that where possible women are assessed by a health professional prior to purchasing the Caya® diaphragm to make sure it fits correctly and to check that the device is inserted correctly to cover the cervix. Written instructions are also available from the manufacturer on how to use the Caya® diaphragm. It is good to practice inserting and removing the diaphragm several times before using it for contraception.
  2. The manufacturer recommends that a teaspoon (about 4 ml) of lactic acid-containing lubricant gel (Caya gel®) be applied to the upper surface of the diaphragm before use. If the diaphragm is inserted more than 2 hours before intercourse additional gel should be applied. In the UK it is recommended that the Caya® diaphragm is used with a spermicidal gel containing the active ingredient called nonoxynol-9 but these products are not available in Australia (Caya Gel® is not a spermicidal gel). Use the dimpled grips and squeeze together the rim.
  3. Caya® diaphragm is inserted a bit like a tampon. Making sure that the arrow on the device is pointing towards the body, insert the diaphragm into the vagina and gently guide it backwards and upwards towards the small of the back as far as it will go
  4. Tuck the diaphragm behind the pelvic bone ridge at the front of the vagina
  5. Check that the cervix is completely covered by the diaphragm by feeling with your fingers (the cervix usually feels quite firm like the tip of your nose)
  6. Following sexual intercourse, the diaphragm MUST stay in place for a minimum of 6 hours as sperm can survive in the vagina for up to this time. While the manufacturer advises that it must not be kept in place for more than 24 hours, it is essential to make sure that it is in place for 6 hours after any episode of intercourse.
  7. Caya® has a dome to facilitate removal. Hook the index finger into the dome to remove, wash with warm water and plain unperfumed soap and leave to air dry before storing in its case.

Ongoing use of the diaphragm

  • If the diaphragm is properly cared for it should last for up to two years.
  • After use, the diaphragm should be cleaned, rinsed, dried thoroughly and stored in a cool place. It should be checked regularly for any holes or signs of wear or feeling "tacky" as this may indicate the silicone is perished.
  • Avoid contact with disinfectants, detergents, powders or perfumed soaps which may weaken and damage the diaphragm.
  • Check with a pharmacist when using any vaginal product, to find out if it is suitable to use with a diaphragm.

What if the diaphragm is dislodged or breaks during sex?

If the diaphragm moves out of place, tears or is not used properly, emergency contraception should be considered.

The Emergency Contraceptive Pill (ECP) can be used to help prevent pregnancy. It is available without a prescription from pharmacies. It should be taken as soon as possible after unprotected intercourse. Contact your Family Planning clinic or GP if you are unsure whether you need to take the ECP.

Where can I get a Caya® diaphragm?

The Caya® diaphragm may be bought from Family Planning clinics and selected pharmacies. Caya® can also be purchased online.

For more information

The information in this Factsheet has been provided for educational purposes only. Family Planning NSW has taken every care to ensure that the information is accurate and up-to-date at the time of publication. Individuals concerned about any personal reproductive or sexual health issue are encouraged to seek advice and assistance from their health care provider or visit an Family Planning NSW clinic.

Updated 15/3/15

The single-size contraceptive barrier device (Caya diaphragm) is a new barrier method of contraception used by women. Find out more.

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