A male contraceptive pill - but will they take it?

British scientists say a male contraceptive pill could be on the market within five years.

The scientists at Kings College London have developed a male contraceptive pill which stops the production of sperm.

They say they have known for a number of years that some drugs used for schizophrenia and hypertension stop the sperm from reaching the penis by stopping the sperm passing from the testes and out of the penis.

They have now isolated the chemical which has this effect and plan to test it initially on animals.

If this proves successful, tests will then be carried out on male volunteers and a male contraceptive pill could be available by 2012.

It is expected that the pill will be taken daily by men, or maybe as a one-off, some hours before intercourse.

The researchers Dr. Christopher Smith and Dr. Nnaemeka I B Amobi, say as the drug works on a muscle rather than hormones, fertility should be restored a day or so after the man stops taking it - even if he had been taking it for several months.

The new development has been welcomed by many, as it offers another reliable form of contraception and also removes the burden from women of taking oral contraception which has been linked to heart problems and blood clots.

However many are skeptical and doubt whether the average male will be prepared to take any drug which interferes with his fertility.

They also question whether men in general can be relied upon to take on the responsibility for contraception and suggest men do not have the same motivation to prevent pregnancies as women.

However the pill for men could offer a less drastic alternative to vasectomy and would enable a man to retain and control his fertility.