One form of contraception will not be a solution for the entire population

Juliet Hillier, Family Planning Association

And 17% were concerned about health problems their partners were experiencing with female contraceptives.

However, 56% of men interviewed said that unknown long-term health problems would put them off taking the pill themselves.

Dr Richard Anderson, who leads male pill trials at Edinburgh University, said: "We don't know the long-term effects of the male pill - we're still learning about the female pill after 40 years.

"But the benefits of pregnancy-free sex are real and immediate."

Commercial trials

Some men admitted they were put off the new contraceptive by some of the side-effects that women taking the female pill have been dealing with for years.

Four out of 10 men surveyed expressed concern about weight gain and 35% said acne would worry them.

The male pill has just entered commercial trials with Dutch pharmaceutical company Organon.

The pill works by "switching off the electricity" to the gonads, halting sperm production almost entirely.

In recent trials it was 100% effective at cutting sperm count to zero.

Testosterone, which would normally also be produced by the gonads, has to be replaced with an implant or injection to maintain libido.

'Effective'

Juliet Hillier, director of communications at the Family Planning Association, said: "These results are not surprising. One form of contraception will not be a solution for the entire population.

"However, research does show some men will find the male pill to be a really effective and useful form of contraception, and that women will trust men to take it."

The survey also reveals other shifts in men's lifestyle attitudes:

• 43% claimed to have cleaned the toilet two weeks in a row
• 38% use moisturiser