Babies 'share womb with tumour'

It is possible to have a healthy baby

Women who develop a rare and traumatic form of cancer during pregnancy can still have a healthy baby, researchers have found.

Doctors usually advise women who develop a condition known as molar pregnancy to have a termination because it has traditionally been thought the risk of allowing the pregnancy to continue is too great.

Our results contradicts previous thinking on this issue

Professor Edward Newlands

However, a study by a team from Hammersmith Hospital and Imperial College London have cast doubt on that approach.

A molar pregnancy is caused by an error in the transfer of genetic information between the sperm and egg during fertilisation.

This results in the egg developing into what is called a hydatidiform mole instead of a normal foetus.

This mole has the potential to develop into a tumour.

Successful pregnancies

Up to three in every 10,000 pregnancies are molar and the risk rises substantially as a woman gets older.

However, one in 100,000 women become simultaneously pregnant with a healthy baby and a hydatidiform mole - which shares sustenance from the mother and grows alongside the healthy foetus as though they were twins.

Ultrasound image of a hydatidiform mole

The new study has found as many as 40% of these women can go on to have a normal healthy birth.

The researchers examined 77 women who had a molar pregnancy and a healthy co-twin.

After the situation was explained to them, 24 of the women opted for a termination.

However, 53 women were keen to continue with their pregnancy and received continual monitoring and careful management of their condition.

A total of 20 women went on to have healthy live births.

The women who decided to continue their pregnancy for as long as possible showed no significant increase in the likelihood of their mole developing into a malignant tumour in comparison to those who decided to have an early termination.

In the small number of cases where the women did develop a malignant cancer, the condition was successfully treated with either chemotherapy or surgery.

Child badly wanted

Lead researcher Professor Edward Newlands said: "Although this condition is not particularly common, the women diagnosed have often tried very hard to become pregnant, have wanted children for a long time or perhaps have little chance of conceiving again.

"In these cases especially the thought of being forced to terminate their pregnancy can be very difficult to bear.

"Our results contradicts previous thinking on this issue and I sincerely hope that they will help to redefine the accepted procedures.

"With no women diagnosed with this condition going on to suffer any lasting complications, I strongly believe that any woman who does find herself in this situation should be given the opportunity to continue her pregnancy through to full term."