Cancer cells
Studies have shown that cancer treatment during pregnancy has no negative effects on babies in the womb Dr. Cecil Fox/National Cancer Institute

Cancer treatment during pregnancy has no negative mental or cardiac effects on unborn babies, studies have shown.

Chemotherapy and Radiotherapy have long been believed to have harmful effects on babies in the womb, with many mothers aborting their child or delaying treatment on the advice of doctors.

However, international studies presented at the 2014 ESMO (European Society for Medical Oncology) Congress in Madrid have shown that it is in fact safe to have cancer treatment while you are pregnant.

"When chemotherapy is administered after the first trimester of pregnancy, we cannot discern any problems in the children," says lead author Dr Frederic Amant, KU Leuven and University Hospitals Leuven in Belgium. "Fear about the risks of chemotherapy administration should not be a reason to terminate a pregnancy, delay cancer treatment for the mother, or to deliver a baby prematurely."

In the first study, 38 children who had been exposed to chemotherapy in the womb were compared to 38 control children, who had not been exposed.

At around the age of two, all of the children were shown to have no significant differences in their mental health.

The cardiac readings also showed that the dimensions and functions were all within the normal ranges.

This is the first study focussing on the effects of chemotherapy on children in the womb and scientists say this shows that chemotherapy during pregnancy can be considered safe for the child.

In the second study, scientists looked at the effect of radiotherapy on an unborn child.

The study assessed 16 children and 10 adults, and found that neuropsychological, behavioural and general health, was within normal ranges.

"The main message is that neuropsychological, behavioural and general health outcomes were within the normal range in all but 3 of the 16 children studied," said Dr Fedro Alessandro Peccatori, from the European Institute of Oncology.

"Pregnancy, particularly advanced pregnancy, has been traditionally considered a contra-indication to radiotherapy. New radiation techniques and more sophisticated simulations of the received foetal dose may change this scenario, but caution remains mandatory when giving radiotherapy to a pregnant woman, particularly in the third trimester," said Peccatori.