Multiple births and fertility treatment

Fertility treatment increases the chance of multiple births

Multiple births are often seen by the media as miracles, but the majority owe more to science than to chance.

The Human Fertilisation and Embryology Authority estimates that at least half of all sets of triplets born in the UK were born as a result of IVF treatment.

And the number is rising year on year. The multiple birth rate has increased from 22.4% in 1995-1996 to 32.2% in the last year.

Fertility doctors are worried at what they see as an unwanted side effect of IVF.

Risky

Multiple births can be risky. The uterus is only capable of carrying, feeding and providing oxygen for a certain amount of foetuses.

This increases the likelihood of babies being born prematurely, developing health problems or dying.

Even twins are more likely to suffer birth defects, such as blindness and cerebral palsy, and are less likely to survive than single births.

To reduce the risks, doctors try to get mothers to have the babies one at a time, but this is not possible in all cases.

In some multiple pregnancies, doctors may recommend that some of the embryos be aborted so that the others have more chance of survival because they have more space to develop.

Professor Ian Craft of the London Gynaecology and Fertility Centre said: "Women who are pregnant with three or more babies can either accept the advice to have just one healthy baby or go for fold and see if they can have them all.

"But there is a high chance of major problems."

Drugs

The most common fertility treatment is drugs which produce extra eggs.

Most women produce only one egg per monthly cycle.

Doctors can increase this number to more than 20, but most prefer to put a limit of two or three because of the risks of multiple births.

Doctors believe multiple births are an unwanted side effects of fertility treatment

The eggs are fertilised in a test tube and doctors normally return the embryos to the womb and wait to see if they develop.

Many doctors are worried that they are being put under increasing pressure to use more of the fertility drugs to produce more eggs and so increase the chance of the woman getting pregnant.

US research shows people undergoing fertility treatment would prefer to have multiple births than have no children.

This is despite reports that those who have multiple births are more likely to suffer depression, anxiety and emotional problems and more prone to divorce.

Too many multiple births

In its recent annual report, the HFEA warns that there are "too many" multiple births occurring as a result of fertility treatment.

Ruth Deech, chairman of the HFEA, said: "Multiple births can be the source of much stress and anxiety for parents.

"There is a greater risk of complications or even miscarriage, as well as long-term disability, and they can cause considerable emotional and financial pressure.

"People undergoing IVF treatment should be aware that as the technique becomes more successful, so the risk of a multiple birth increases."

The HFEA, which regulates and licenses fertility clinics under the 1990 Human Fertilisation and Embryology Act, is monitoring developments concerning multiple births.