Epidemiology

2% of women aged 16-49 use diaphragms, caps, sponges or female condoms.^[2] Their popularity as forms of contraception has declined with the availability of more effective methods. However, they still offer options to those who are unable to use other forms through personal preference or contra-indications, or for those who desire a female-controlled form of contraception.

Indications

They are potentially suitable for use by most women, as they are non-hormonal forms of contraception. However, the relatively high failure rate should be taken into consideration.

Diaphragms

Diaphragms are thin, dome-shaped devices made of latex or silicone and range in size between 55 mm and 100 mm.

Diaphragms should lie diagonally between the posterior fornix and behind the pubic bone. They come in three styles:

• Flat spring - these are firm and are suitable for women with normal vaginal musculature and particularly those with a shallow arch behind the symphysis.
• Coil spring - these have a softer spring and may feel more comfortable. They are suitable for women with a normal pelvis and deep pelvic arch.
• Arcing spring - these fold at two points, making them easiest to insert. They are useful for women with poor vaginal muscle tone or those with a retroverted uterus.

Caps

Caps are smaller than diaphragms and sit directly over the cervix, held by suction. In the UK they tend to be reserved for women who have had problems with the diaphragm.

Rubber caps

• Prentif Cavity Rim® cap - thimble-like and fits directly over the cervix. The cervix needs to have straight, parallel sides and point along the long axis of the vagina. Sizes 22-31 mm.
• Dumas Vault® cap - this adheres to the vaginal wall and is suitable where there is a flattish cervix. Sizes 1-5.
• Vimule® - similar to the vault cap but has an elongated dome so it fits a longer cervix. Sizes 1-3.

Silicone caps

• FemCap® - can be used for three days in total. Sizes 22-30 mm.

NB: Oves® cap is no longer available.

Female condom

Available as Femidom®.

This is a loose-fitting polyurethane sheath with two flexible polyurethane rings - one at either end. It sits in the vagina. At the closed end of the tube the ring is not fixed but helps make insertion easier. It also acts as an internal anchor. At the open end, the flexible ring lies outside the vagina. It is lubricated with non-spermicidal lubricant. No fitting is required.

Instructions for use

Never re-use a female condom. Always check the expiry date.

• Take care not to damage with fingernails or jewellery when removing it from the packet.
• It may be inserted any time before sex, but must always be in position before the penis touches the genital area.
• In a comfortable position - eg, squatting or one leg up on a chair - hold the closed end of the condom and squeeze the ring between the thumb and middle finger.
• Using the other hand to open the labia, push the ring as high into the vagina as possible.
• Place the middle finger into the open end of the condom and try to feel the inner ring. Push it high into the vagina.
• Make sure the outer ring is lying close to the vulva. It is advisable to guide the penis into the condom, to avoid slipping between condom and vagina.

To remove the condom, twist the outer ring (to trap semen inside) and pull gently.

Contraceptive sponge

This is available as Today®. It is made of polyurethane and is 6 cm in diameter and 1.5 cm thick. It is impregnated with nonoxynol-9 spermicide. No fitting is required. Maximum recommended duration of use is 30 hours.

• It is fitted into the vagina prior to sexual intercourse and works by occluding the cervix, releasing spermicide, and absorbing semen.
• The sponge needs to have water applied to activate the spermicide.
• It is inserted into the vagina by hand. There is an indentation on one side which helps to place it against the cervix.
• There is a loop that makes removal easier.
• The sponge may be inserted up to 24 hours before sex and removed any time after six hours.

Contraceptive efficacy

• With barrier methods, efficacy is largely user-dependent, the keys to success being good fitting, patient education and motivation.^[1]
• When used according to instructions (with spermicide), diaphragms have a first-year failure rate of 4-8% and caps 9-26%.^[3] 
• Parity increases the risk of failure with women who use the cap.
• A comparison of two types of cap to the diaphragm showed the Prentif® cap (similar design to Oves® cap) to be comparable to the diaphragm in preventing pregnancy but the FemCap® is thought to be less effective.^[4]
• The use of spermicide is advocated with these methods, although a Cochrane review failed to prove its contraceptive contribution.^[5]
• First-year probability of failure during perfect use is 11-12% for the sponge, rising to 17% during typical use. Higher rates of failure are seen in parous women.^[6]
• Typical use first-year failure rates are 15% for the female condom.^[7] Perfect use first-year failure rate is around 5%, showing it can be highly effective.

Advantages

• No serious side-effects.
• Female-controlled.
• Good choice where fertility is reduced (eg, breast-feeding, perimenopause).^[8]
• More independent of intercourse than condoms, allowing greater sexual spontaneity.
• No loss of sensation.
• Diaphragms and caps may be preferred to female condoms as female-controlled barrier methods, as there is less perceived interference with sexual pleasure.

Disadvantages

• Less effective than other methods.^[8]
• Requires motivation and careful use.
• Requires some forward planning and confidence examining one's genitals.
• Must be used with spermicide which can make it messy, and cause irritation or allergy.
• The female condom is noisy.
• Diaphragms and caps require fitting on at least an annual basis and education from a trained health professional.
• Little evidence of protection from sexually transmitted infections (STIs).^[3] 
• May increase risk of urinary tract infections (UTIs) - mostly with diaphragms.

Contra-indications

These are taken from the UK medical eligibility criteria (based on the World Health Organization (WHO) criteria).

• The patient is known to have, or is at high risk of, HIV/AIDS; evidence of repeated high-dose use of the spermicide nonoxynol-9 is associated with increased risk of genital lesions, which may increase the risk of acquiring HIV. However, the consistent and correct use of female condoms may reduce the risk of HIV transmission.
• History of toxic shock syndrome.^[8][9] The use of a diaphragm, cervical cap or contraceptive sponge is not generally recommended, but they may use a female condom.
• Acute vaginitis or concurrent pelvic infection - treat first.
• Woman unable to insert or remove device.
• Anatomical constraints - inadequate retropubic ledge, or uterovaginal prolapse. However, cervical/vault caps may be possible. Also, markedly anteverted cervix or septate vagina.
• Abnormal cervical smear or biopsy in the preceding 12 weeks.
• Recurrent UTIs.
• Rubber allergy (consider a silicone device). These women can use a silicone diaphragm or cervical cap, or a polyurethane female condom.
• Spermicide allergy.

Initial visit: caps and diaphragms

• Counsel fully to check the method is acceptable to the woman and that she is fully informed regarding risks/benefits, and provide reinforcing written information.
• Pelvic examination to assess suitability. The bowel and bladder should be emptied prior to fitting. Ideally, caps should be fitted mid-cycle.
• Select a size for a practice device (for a diaphragm, this should approximate the distance from behind the cervix to the pelvic arch).
• Start with the largest size that is comfortable. Check that the device does not fall out when the woman ambulates or performs a Valsalva manoeuvre.
• Teach the woman how to remove and insert the device. It is important that the woman should be aware of what her cervix feels like and how to check that the device fully covers the cervix when in the correct position.
• To insert a diaphragm, put your index finger on top of the diaphragm and squeeze it between your thumb and other fingers. Slide the diaphragm into the vagina in a downwards and posterior fashion. Some women find it easier to squat and others to lie down for insertion.
• To insert a cap, squeeze the sides of the cap together and hold between the thumb and first two fingers, allowing it to 'suction' neatly over the cervix.
• The woman goes home with a practice device. She must be aware not to rely on it for contraception until after the second visit.

Second visit

The woman should return with the device in situ to enable the positioning and size of the device to be checked. Any problems the woman has encountered fitting it should be fully explored.

Give specific instructions:

• Insert the device before sexual intercourse.
• Always use with spermicide.
• Use a total of 10 cm cream or jelly or one pessary (allowing 10 minutes to dissolve fully).
• Spermicide is only active for three hours, so if intercourse continues for longer than three hours, re-insert spermicide.
• Leave the device for at least six hours following sexual intercourse, but for no more than 30 hours.
• After removing the device, wash it in warm water and soap if required and dry before putting it away.
• Never use with oil-based products (eg, antifungal formulations, oestrogen creams, emulsifying ointment, Vaseline®, and massage oils), as these can cause the latex to decay more rapidly.
• Check for puckering and holes - if present, the device should be replaced urgently.

Monitoring

Follow-up should be on an annual basis since devices should be replaced at that interval (unless there is earlier evidence of damage):

• Any weight change of more than 3 kg should prompt a review.
• Fitting should also be checked after childbirth (at least six weeks postpartum), termination or miscarriage.

Reasons for women discontinuing use of diaphragms include:

• Difficulty with removal and insertion.
• Perception that leaving the diaphragm in the vagina after sex is 'dirty'.
• Desire for a more reliable form of contraception.^[10]

Complications

• Difficulty with insertion:
  • Try a different size.
  • Try an arching spring diaphragm.
  • Try an applicator.
• Recurrent UTIs:
  • Advise women to empty the bladder before and after intercourse.
  • Try a smaller size or coil spring diaphragm.
  • Change to a vault or cervical cap.
• Vaginal soreness:
  • Check size.
  • Treat any infection.
  • Try an alternative spermicide.
  • Consider rubber allergy.
• Partner feeling the device:
  • Check size.
  • Change to coil spring device.
  • Change to a vault or cervical cap.