Macho, sexy - and with a cigarette dangling from the mouth. That is the Hollywood stereotype.

In Ian Fleming's James Bond novels, Bond could smoke up to 70 cigarettes a day and yet remain unflagging in bed.

The early Bond movies also kept up this image.

However, Dr Peter Lim, senior consultant urologist at Gleneagles Hospital, said smoking can cause male sexual problems like Erectile Dysfunction (ED) and infertility.

ED is the persistent inability to attain and maintain penile erection adequate for satisfactory sexual performance.

Smoking causes ED when it causes fatty deposits to build up in the arteries supplying blood to the penis.

This results in low penile blood pressure that decreases the flow of blood to the penis.

Further reduction in blood flow can also result from rapid contractions in the penile tissue that restrict arterial blood flow into the penis.

This is a direct result of nicotine stimulation in the brain.

Nicotine in the bloodstream also causes excessive outflow from veins in the penis and this reduces the duration of an erection.

There is more bad news. Men who smoke cigarettes have lower sperm count and motility.

There are also increased abnormalities in sperm shape and function.

Yet if a smoker chooses to stop smoking, sperm motility almost always improves, though the other effects will improve only if the arteries are not permanently hardened and damaged.

Dr Lim noted that smoking causes infertility within months and ED within four to five years.

Women not spared

Women smokers are not spared either.

They have decreased egg counts and are more likely to have painful and irregular menstruation.

They have an increased risk of early menopause and are four times more likely to suffer from cervical cancer.

Should female smokers become pregnant, they also face an increased risk of miscarriages and are twice as likely to have an ectopic pregnancy.

An ectopic pregnancy is when the fertilised egg grows outside the uterus.

Smoking is also responsible for 15 per cent of premature births.

There is help in Singapore if you want to quit.

You can call the QuitLine on 1800-438-2000, where professional advisers will guide you.

Alternatively, you can join the smoking cessation sessions offered at polyclinics and hospitals.

This article was first published in Mind Your Body, The Straits Times.