SMOKING mothers have babies who cough, wheeze, and cry more than usual, according to two new pieces of medical research.

Previous warnings of increased risks to unborn and newborn infants have been well documented, but now it appears that the chances of both colic and asthma increase with smoking, claim the reports.

Colic, a curse for many new parents, was defined by a Dutch research team as crying for more than three hours a day on more than three days a week.

The team from the Institution of Prevention and Health in Leiden found colic was twice as likely where mothers smoked 15 to 20 cigarettes a day.

More than 3000 babies aged up to six months were monitored for ''crying behaviour'' for the report in BMJ journal Archives of Disease in Childhood.

Breast-fed babies were less likely to pick up colic than bottle-fed infants for both smoking and non-smoking mothers.

A separate report in the same publication found wheezing and asthma risks also increased when mothers smoked during pregnancy.

The British research, by Dr Andrew Lux of the Royal United Children's Hospital in Bath, surveyed 8500 mothers about smoking during pregnancy.

It discovered around one in five children were consistently wheezy between the ages of 18 to 30 months and four in 10 suffered occasionally.

Smoking mothers to be increased the risk but the increase was similar whether the woman smoked a little or a lot, the research claims.

It also pointed to other factors which can cause problems.

These include living conditions, asthmatic parents, and whether the baby was delivered prematurely.

Monitoring all the factors the report concluded: ''Smoking during pregnancy, and environmental tobacco smoke, are likely to account for around 1.5% of wheeziness in all young children.''

qA study claiming disposable nappies could cause male infertility was yesterday rejected as ''scientifically flawed and irresponsible'' by a nappy industry spokesman.

Scientists at Kiel University in Germany claim to have found that plastic-lined nappies significantly heat up baby boys' scrotums, which could harm normal testicular development.

The modern preference for disposable nappies could account for the rise in male infertility over the past 25 years, it is claimed.

The new research, published in the British Medical Journal, found that disposable nappies raise the scrotal temperature by as much as one degree above body temperature.

High scrotal temperatures are known to reduce sperm counts in adults.