In fact, research by scientists in the United States has revealed that the level of symmetry of a person's hands and the length of his or her fingers is a fair indicator of the fertility level, says a report in New Scientist.

In the course of treatment of 60 men and 40 women, attending a fertility clinic, some of whom had severe fertility problems, Dr John Manning and his colleagues at the University of Liverpool found that men with the least symmetrical hands -- where one hand is not a mirror image of the other -- had the lowest sperm count and the lowest sperm mobility.

In fact, 12 of Dr Manning's patients, who were producing almost no sperm, had assymetries of up to four millimetres between their hands.

Explaining the results, Dr Manning says, ``Digit assymmetry predicts the number of sperm per ejaculate. The more the assymetry, the fewer the sperm.''

During the research, Dr Manning also looked at therelative length of the fingers. For reasons no one has been able to explain, men tend to have ring fingers that are longer than their index fingers whereas in women the two fingers tend to be of the same length.

Dr Manning found that men whose ring finger is much longer than their index finger tended to have higher levels of the male sex hormone testosterone, which plays a role in fertility.