2.5 million British men suffer from low fertility - but most don't know it

Fertility problems are often thought of as a woman's problem. But more than a third of infertility problems can be attributed to men. According to this study, 9% of British men suffer from poor fertility, and this problem seems to be becoming more prevalent with time.

The most likely culprit is smoking, followed by drinking, and stress. Other possible causes of infertility are excess weight, pesticides, pollutants, and female hormones in the water supply from the urine of women who take hormone pills.

Smoking is not just bad for your fertility, it may also have an effect on the gender of your offspring. This study from 2002 found that cigarette smoking makes it less likely that your child will be a boy. Normally, more boys are born than girls (although this usually evens out later in life because of the higher mortality among males). This study found that:

the sex ratio was 1.21 boys to every girl in the group in which neither parent smoked... However, it fell to 0.82 boys to every girl in the group where both mother and father smoked more than 20 cigarettes a day. The ratio of male births was also reduced to 0.98 boys to every girl among couples where the mother was a non-smoker, but the father smoked more than 20 cigarettes a day.

This means that smoking makes it more likely that you will have a girl. Researchers suspect that the y chromosome, which determines maleness, may be more sensitive to damage caused by smoking.

So couples who want to have a boy should make it a point to quit smoking today. But this doesn't mean that someone who wants to have a girl should take up smoking. Smoking has many negative effects on the fertility of men and women and on their offspring, and should be avoided by anyone wanting to conceive healthy children.

Scientists also suspect that certain industrial pollutants might make it more likely for those exposed to have male children. No matter how desperately someone may want a boy, exposing oneself to harmful pollutants is a bad idea. Utimately, everyone's first priority should be to have a healthy baby, regardless of gender.

Besides, there are other ways to select the sex of your baby. They just happen to be very expensive.

But considering what some people will do just to have a boy, maybe it is better for them to just bathe in pollutants. Sure beats female infanticide.