Researchers have zeroed in on groups of genes which behave differently in women more likely to become pregnant using in vitro fertilisation (IVF). A simple blood test could spot the crucial gene group.
The groups of genes were linked to processes in the body which could affect fertility, including inflammation, the growth of new blood vessels, and damage to individual cells.
Only around a third of IVF treatments are successful, and women can go through six or more cycles of the treatment, which can be expensive and involve large amounts of fertility drugs as well as emotional and physical stress, without becoming pregnant.
The blood test proposed could help end the agony of women who find it hard to decide whether to try another cycle of IVF if previous attempts have failed.
The Irish study tested samples of blood from the arms of 64 women before they began IVF treatment.
Analysis of more than 30,000 genes in each woman up showed "clear patterns" of difference in the behaviour of genes in those who successfully became pregnant and those who did not.
The research was presented at the European Society of Human Reproduction and Embryology (Eshre) conference in Amsterdam.
Dr Cathy Allen, from the Rotunda Hospital in Dublin, who led the research, said: "There does seem to be a particular signature that goes with early human pregnancy.
"We're talking about a unique profile that has the potential to be used in future to predict IVF success or failure.
"The work is in its infancy and has to be developed and validated, but we hope it will improve the blunt prognostic procedures we have now."
She added that it would be a few years before doctors would be able to offer such as test to women undergoing fertility treatment.
But the test had the potential to help women make the "difficult" decision on whether to continue with IVF treatment, about 45,000 cycles of which are carried out in Britain every year.
"IVF technology has advanced tremendously over the past three decades, yet success after IVF remains an unpredictable outcome," said Dr Allen. "Our work will help understand whether the implantation of embryos is influenced by the constantly changing expression of human genes."
However, the test is expected to be expensive, costing, at least initially, at least a few thousands pounds.
Prof Luca Gianaroli, the chairman of Eshre, said that such a test had the potential to benefit many women suffering from fertility problems.
He added that costs would eventually fall: "When high technology is involved you can expect that costs will be reduced.
"In the meantime this test could save a lot of unnecessary treatment. You have to balance the cost of research and the benefits of research."
Private cycles of IVF for women who do not qualify for treatment on the NHS cost around Ģ3,000, Telegraph reported.