The main forms of barrier contraception are the condom and the diaphragm.
The condom is the simplest barrier method of artificial contraception and the only reversible contraceptive so far developed that is used by men. A condom is a thin rubber sheath that is placed on the penis before penetration. When the man ejaculates, the sperm are held in a reservoir at the tip.
Condoms have the advantage that they are cheap and readily available. They are not completely foolproof because the rubber can tear or they can come off, but if they are used in accordance with instructions they are very effective. Used with a spermicide, the failure rate has been estimated as only 3%.
Condoms have the further advantage that they not only protect the woman against becoming pregnant, but they may also protect both partners against some sexually transmitted diseases, and since the advent of the AIDS virus, anyone engaging in sex with a partner who is not long-term and well known to them should use a condom.
Some men complain that the rubber lessens the sensation (“like showering with a raincoat” is a common analogy), but modern ultra-thin rubbers reduce this disadvantage considerably, and the risks of engaging in unprotected sex in this day and age make such objections foolish in the extreme. On the other hand, men who suffer from premature ejaculation may be helped by a thicker condom as it reduces sensation slightly.
Condoms are not new. In eighteenth century France, the renowned philanderer Casanova used a thin pig’s bladder as an early condom or “French letter”. Prior to this there were similar devices made from leather or gut, which were far less comfortable.
The condom is named after Lord Condom, the court doctor to England’s King Charles II who was a renown philanderer and requested his doctor to develop a way of protecting his royal member from syphilis. The eponymous doctor devised a closed sleeve of sheep intestine for the king.
As an historical curiosity, in the 1920s, condoms were considered a danger to the wellbeing of a woman as it was considered necessary for a woman to absorb semen from her vagina on a regular basis to maintain good health.
The diaphragm is a contraceptive device used by women that provides a physical barrier to the sperm meeting the egg.
It is a rubber dome with a flexible spring rim, and is inserted into the vagina before intercourse, so that it covers the cervix (the entry to the uterus). It should be used with a spermicidal cream or jelly to kill any sperm that manage to wriggle around the edges.
A woman must be measured by a doctor for a diaphragm of the correct size and she will also need to be instructed how to insert it properly.
Most women find a diaphragm easy enough to use, and it has a high reliability. Some women find the fact that it has to be inserted before intercourse aesthetically displeasing, but generally it presents no problems. It can be put in place some time before if necessary, but must be left in place for at least six hours after intercourse to ensure that all the sperm are dead before removal. Its failure rate of between 10 and 15% makes it less reliable than condoms.