Barrier
methods%Failure Rate of various barrier methods
| Barrier Method | Perfect Use | Typical Use |
| Condoms – Male | >3 | >14 |
| Condoms – Female | >5 | >21 |
| Diaphragm | >6 | >20 |
| Sponge | >9 - 20 | >20 - 40 |
| Cap | >9 - 26 | >26 - 40 |
| Spermicides | >6 | >26 |
| (Withdrawal method | >4 | >19) |
A higher failure rate is found with the cap or sponge, if the woman has had a baby.
Barrier methods of contraception have been used from earliest times and their effectiveness depends on their quality of use and by the motivation of individuals. Whilst not as effective as some other methods of Family Planning (oral, injectables, implants, IUDs), many women prefer a method that does not involve taking hormones. Barrier methods may also be a choice where pregnancy would not be unwelcome and/or fertility is lower (breast-feeding and aged >40). Barrier methods have the advantage of being reversible, reliable, without side effects and are the method of choice by many people. Condoms are a barrier method that has also been promoted as a method of reducing the risks of Sexually Transmitted Diseases (STIs), either used on their own or with other methods of contraception e.g. oral contraception.
Diaphragm
The diaphragm consists of a thin, latex rubber hemisphere with a rim made of a coiled metal spring. A specially trained practitioner must do the sizing and fitting of the device. It is inserted before intercourse, usually using a spermicidal cream as well. If intercourse takes place more than 2 hours after insertion, then more spermicide should be inserted into the vagina. The diaphragm is left in situ for at least 6 hours following intercourse, before removal. After use, the diaphragm needs to be washed in soapy water and dried carefully.
The diaphragm needs to be checked 1 - 2 weeks after fitting. It also needs to be checked for size and fit if the women gains 4 kg in weight, post partum and renewed at least annually.
Advantages
- No systemic side effects
- Effective if correctly fitted and used correctly
- Does not affect breast-feeding
- Use of spermicide increases effectiveness and helps with lubrication
- Less risk of PID and ?cervical disease
- Less reduction of sexual sensitivity as may be found with condoms.
Disadvantages
- Requires premeditation and can be ‘messy’
- May cause discomfort and loss of cervical sensation
- Has to be fitted and checked by a trained practitioner
- Does not protect against HIV and other STIs
- Allergy to spermicide or latex
- Higher incidence of thrush and UTIs
- Toxic shock may rarely occur if the device is forgotten and left in situ.
- Failure rate increases with incorrect fitting, loss of fit and lack of motivation
Contraindications
- Poor vaginal muscular support or prolapse
- Aversion to using diaphragm or inability to touch genital area.
- Inability to learn how to insert device, or lack of hygiene or privacy for insertion.
Cervical Cap
This device is similar to a diaphragm but much smaller, covering the cervix only. Like the diaphragm, it needs to be fitted by a trained practitioner. The main advantage over the diaphragm is that it can be used for women with poor vaginal muscle tone and occasionally if there is a prolapse present. It is not likely to be felt by the partner and there is no loss of vaginal sensation. The fitting is not affected by weight change and can be left in situ for several days. It is less likely to cause urinary symptoms than the diaphragm. However, it requires accurate sizing and an undamaged cervix. There should not be any purulent discharge present. The device is more difficult to insert and site correctly over the cervix. If left in situ too long it may cause an unpleasant odour.
Vault Cap
This device lies somewhere between the cervical cap and the diaphragm, in size. The methods of use and instructions for fitting are similar to those for the diaphragm.
Condoms – Male
Condoms are one of the few contraceptive methods for men that not only are effective and reversible, but also provide some protection against STIs and HIV. There are a large range of types and sizes of condoms available and they are usually made of latex and lubricated with a spermicide. There are coloured, scented and textured variations. For those who are sensitive to latex or lubricants, there are low allergy condoms made without lubrication. There is also a thicker variety, more suitable for anal intercourse and homosexual males, giving greater HIV protection. Condoms are also made from polyurethane and sheep’s intestine.
The effectiveness of condom use varies widely from 3% failure rate to 23%, depending on the correct method of use and the motivation of the users. Obviously the partner’s motivation and level of fertility plays a part. An ill-fitting condom is more likely to fail and it should be put on prior to intercourse and not prior to ejaculation.
There are few contraindications to the use of condoms – namely, if either partner objects to using them, has an allergy to them or has a malformation of the penis. However, certain oils and lubricants can destroy the strength of the condom and lead to failure. If a known failure has occurred – condom breakage or slipped off during intercourse, then the partner should be encouraged to seek immediate advice for emergency contraception and, if at risk, possible screening for STIs.
Advantages
- Reliable and reversible method if correctly used.
- Widely available and free on request from WCSS or Tweedmouth F. P. Clinic.
- Easy to use with usually no side effects.
- High level of protection against STIs and HIV.
- Protection against cervical diseases
- Improves performance if suffers from premature ejaculation.
Disadvantages
- Unattractive appearance and can decrease spontaneity
- Some decreased sensitivity
- Increase in erection difficulties.
Instructions for Use
- If not pre-lubricated, the woman should use a recommended lubricant, prior to intercourse e.g. KY jelly.
- The condom should be unrolled onto the erect penis before any contact with the vulva is made, leaving the tip of the condom empty to accommodate the ejaculate.
- During withdrawal, the condom should be held firmly at the base of the penis so that it remains in place until after the penis has been withdrawn.
- The penis should be washed before any further contact with the woman occurs.
- Disposable condoms should not be re-used.
- Condoms should not be used after the expiry date.
- Oil-based lubricants such as Vaseline, baby oils and petroleum jelly reduce the strength of a condom by 50% within 15 minutes.
- Condoms users should advise their partners of emergency contraception in the event of a failure.
Condoms – Female
The female condom consists of a polyurethane sac and has an outer ring worn at the introitus and an inner ring that acts like the ring of a diaphragm, keeping it in position against the cervix. It is resistant to damage by chemicals. The female condom or Femidom is not so widely used as the male condom, perhaps because it can found to be more embarrassing to use and it has been reported to sometimes make a ‘rustling noise’. However, it is an effective and reversible method when used correctly and the user is well motivated. It also has similar advantages to the male condom, providing some protection against STIs. It should be inserted into the vagina prior to intercourse and although the penis does not have to be fully erect, care should be taken that it does not become wrongly positioned between the Femidom sac and the vaginal wall.
References
- Glasier,A Gebbie,A Family Planning and Reproductive Health Churchill Livingstone
- Guillebaud,J Contraception Today Taylor and Francis