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A "personalised predictor" model could help women decide whether their next cycle of IVF is going to succeed, say US researchers.

A team from Stanford University in California developed the model using clinical data from a patient's previous failed IVF treatment.

About 75% of in vitro fertilisation treatments do not result in a live birth.

The research appears in Proceedings of the National Academy of Sciences.

Women who have gone through this experience are often unsure whether to try IVF again.

It is well known that the procedure carries financial, physical and emotional costs - and there are no guarantees it will work.

Doctors from Stanford University School of Medicine say they set out to develop a way to provide patients with more personalised predictions, which were not just based on age.

They analysed the outcomes of more than 1,600 first-time IVF treatments and used these to predict whether a second IVF treatment would result in a live birth.

In doing so, researchers identified 52 factors that influence a woman's chances of having a baby - including patient age, levels of certain hormones, number and quality of eggs and individual characteristics of each embryo.

Researchers then tested their model on a separate set of IVF treatments, which showed that their test's predictions were significantly different to age-based predictions in 60% of patients.

Mylene Yao, assistant professor of obstetrics and gynaecology at Stanford University and lead author of the paper, said the findings indicated that "the current age-based paradigm may provide misleading live birth outcome probabilities for a large portion of patients".

Having personalised prognostic information, she added, "would be invaluable in assisting women's decisions to keep going or not with IVF".

The paper defines "live birth" as the delivery of a live baby beyond 24 weeks of gestation.

The model relies on data from previous IVF cycles, so it would not be able to predict the chances of success for those undergoing their first IVF treatment.

Dr Allan Pacey, fertility expert and senior lecturer at University of Sheffield, said: "IVF doctors inherently do more than just look at age. We look at lots of factors before talking to patients about their chances of success using IVF."

He added: "There have been a few attempts to create predictor models before, but to have universal appeal the model must work well in lots of different clinics.

"IVF is not an exact science, so we've got to be careful not to give people false hope."