Barrier Methods of Contraception

 

A variety of barrier methods of contraception are available at present for both male and female. The aim of these methods is to prevent live sperm from meeting the ovum. Unlike other methods of birth control, barrier methods are used only when you have sexual intercourse. Barrier methods require a high degree of motivation on the part of the user. These methods are only effective if they are used consistently and carefully. 

There are two types of barrier methods of contraception, physical methods and chemical methods.

Physical Methods of Contraception

[A] Condom 

Condom is the most widely known and used barrier device by the males around the world. Condom is receiving new attention today as an effective simple "spacing" methods of contraception, without side effects.

The condom is fitted on the erect penis before intercourse. The air must be expelled from the teat end to make room for the ejaculate. The condom must be held carefully when withdrawing it from the vagina to avoid spilling seminal fluid into the vagina after intercourse. A new condom should be used for each sexual act.

Condom prevents the semen from being deposited in vagina. The effectiveness of a condom may be increased by using it in conjunction with a spermicidal jelly inserted into the vagina before intercourse. The spermicide serves as additional protection in the unlikely event that the condom should slip off or tear.

Condoms can be a highly effective method of contraception, if they are used correctly at every coitus. Failure rates for the condom vary enormously. Most failures are due to incorrect use.

Male condom

Advantages of Condom:

1. They are easily available.
2. No side effects
3. Light, compact, and disposable.
4. Safe and inexpensive.
5. Provide protection not only against pregnancy but also against sexually transmitted diseases.

Disadvantages of Condom:

1. It may be slip off or tear during coitus due to incorrect use.
2. Interferes with sex sensation locally about which some complain while others get used to it. 
3. The main limitation of condoms is that many men do not use them regularly or carefully, even when the risk of unwanted pregnancy or sexually transmitted disease is high.

Female condom

The female condom is a pouch made of polyurethane, which lines the vagina. An internal ring in the close end of the pouch covers the cervix and an external ring remains outside the vagina. It is pre-lubricated with silicon, and a spermicide need not be used. It is an effective barrier to STD infection. However, high cost and acceptability are major problems.

Female condom

[B] Diaphragm / Cervical Cap

The diaphragm is a vaginal barrier. It was invented by a German physician in 1882. Also known as "Dutch cap" and "Cervical cap". The diaphragm is a shallow cup made of synthetic rubber or plastic material. It ranges in diameter from 5-10 cm. It has flexible rim made of spring or metal. It is important that a women be fitted with a diaphragm of the proper size. It is held in position partly by the spring tension and partly by the vaginal muscle tone. This means, for successful use, the vaginal tone must be reasonable. Otherwise, in the case of a severe degree of cystocele, the rim may slip down. 

The diaphragm is inserted before sexual intercourse and must remain in place for not less than 6 hours after sexual intercourse. A spermicidal jelly is always used along with the diaphragm. Side-effects are practically nil.

If the diaphragm is left in the vagina for an extended period, there is a remote possibility of a toxic shock syndrome.

Cervical Cap / Diaphragm 

Advantage of Diaphragm

The primary advantage of the diaphragm is the almost total absence of risks and medical contraindications.

Disadvantages of Diaphragm

1. Initially a physician or other trained person will be needed to demonstrate the technique of inserting the diaphragm into the vagina and to ensure a proper fit.
2. After delivery, it can be used only after involution of the uterus is completed. 

[C] Vaginal Sponge

A contraceptive sponge is a soft, disk-shaped device made of polyurethane foam that contains spermicide but it is only recently one has been commercially marketed in USA under the trade name TODAY for the sole purpose of preventing conception. It is put deep inside the vagina before sex. 

It is a small polyurethane foam sponge measuring 5 cm × 2.5 cm, saturated with the spermicide. The sponge is less effective than diaphragm.

Vaginal sponge

Chemical Methods of Contraceptives

In the 1960s, before the advent of IUDs and oral contraceptives, spermicides (vaginal chemical contraceptives) were used widely. They comprise four categories.

1. Foams : Foam tablets, Foam aerosols
2. Creams, jellies, and pastes - squeezed from a tube
3. Suppositories - inserted manually
4. Soluble films - C-film inserted manually 

The commonly used modern spermicides are "surface active agents" which attach themselves to spermatozoa and inhibit oxygen uptake and kill sperms.

The spermicide should be free from potential systemic toxicity. It should not have an inflammatory or carcinogenic effect on the vaginal skin or cervix. No spermicide which is safe to use has yet been found to be really effective in preventing pregnancy when used alone. Therefore, spermicides are not recommended by professional advisors. Recently there has been some concern teratogenic effects on the  fetuses', following their use. However, this risk is yet to be confirmed. 

Effectiveness of Barrier Methods of Contraceptives

Barrier methods of contraceptives effectiveness