Babies of methadone mothers develop eye defects, say experts

BABIES born to mothers who take methadone during pregnancy have developed a range of visual problems, according to a report by medical experts in Glasgow.

The study discovered that the mothers of all 20 infants referred to a specialist clinic for vision defects had taken opiates during pregnancy.

The problems included blurred vision, nystagmus (rapid and involuntary eye movement from side to side), squints, short-sightedness and cerebral visual impairment – signs that the brain was not processing the signals from the eyes correctly.

The results of the study are likely to add to the controversy surrounding the prescription of the heroin substitute methadone to drug users.

The latest official statistics show that 572 babies were born to drug misusers in 2006-7, including 370 births to users of opiates such as methadone and heroin. The study, published in the Scottish Medical Journal, was carried out by doctors at the Royal Hospital for Sick Children at Yorkhill and Princess Royal Maternity. It is the first major investigation into how the use of opiates during pregnancy affects the development of vision in babies.

Researchers said there were "growing concerns" about the scale of the vision problems being picked up by eye examinations and about how long they would persist.

Neonatal consultant Helen Mactier said: "We were seeing a disproportionate number of babies who had visual difficulties whose mothers had a history of drug abuse."

Ruth Hamilton, a consultant clinical scientist and an expert in vision who is involved in the research project, said: "This is about the long-term outcomes for these children. It may be that these babies will go on to develop problems later in life, and it is very important that we discover if there is something we can do."

In the study, 19 babies had blurred vision, 14 nystagmus, six had squints, six were short-sighted and five had cerebral visual impairment.

A preliminary summary of the research has been presented to the Scottish Paediatric Society. It suggests routine eye examinations for children who were exposed to methadone in the womb, saying: "Children with a history of in-utero opiate exposure may benefit from a vision screening programme."

Mactier said:

"We deliver 150 babies a year to drug-using women and around 45 per cent of them are treated for withdrawal. These babies stay in hospital for a longer period, they are often sick and small. Their mothers are often heavy smokers, they may be from very socially deprived backgrounds, they have a high risk of depression.

"There is an increasing amount of evidence that babies born to drug-addicted mothers have a whole range of health problems."

She said that, because of the often chaotic lifestyle of drug users, it was hard to single out methadone or any other factor as the principal cause of eye problems.

"Between two-thirds and four-fifths of women on prescribed methadone are also using illicit opiates, valium or similar drugs."

A secondary study will try to pinpoint which factors were most likely to cause of eye problems in the babies of drug-abusing mothers.

There are now 22,000 addicts in Scotland on a methadone programme. A study by Glasgow University's Centre for Drug Misuse Research found that people on methadone programmes still take heroin. There are concerns the programme replaces one addictive drug with another, and that people are "parked" on methadone for years. There have also been cases of addicts' children gaining access to methadone.

Earlier this month, the 50 million policy was criticised when an addict's free supply was cut after almost 20 years.

A Scottish Government spokesman said official policy was to recommend methadone treatment for pregnant drug users on the grounds that prescribed drugs carried a lower risk than continuing to use illegal drugs.

He said: "Pregnant women who misuse drugs receive extra support and care suited to their personal needs."