The old advice given to infertile couples that if they just stop stressing about getting pregnant, it'll happen on its own, just might be good advice, doctors report.

Research presented at this week's meeting of the American Society for Reproductive Medicine in Atlanta finds that women who took part in a stress management program while having a second round of assisted fertility treatment had a 160 per cent greater pregnancy rate than women who skipped the stress program.

Dr. Alice Domar, who runs a fertility centre in Boston and also works at Harvard Medical School, says the results of her study should be encouraging to couples undergoing in vitro fertilization (IVF).

"Reproductive health experts have long wondered about the impact that stress may have on fertility, thus impeding a woman's ability to conceive," Domar said in a statement.

"This study shows that stress management may improve pregnancy rates, minimizing the stress of fertility management itself, improving the success rates of IVF procedures, and ultimately, helping to alleviate the emotional burden for women who are facing challenges trying to conceive."

The study, Domar and colleagues randomly assigned 97 patients at her clinic to take part in a mind/body program while undergoing IVF.

The program was designed to educate women on how to use cognitive, relaxation and lifestyle techniques to manage stress. Over 10 sessions, couples were taught relaxation training, cognitive-behavioral strategies and participated in group support.

The program had no effect on how many women conceived during their first IVF try, Domar told the meeting, with 43 per cent of the women getting pregnant.

But for women who failed the first time and were completing a second IVF cycle, 52 per cent who took part in the mind/body program became pregnant, compared to only 20 per cent of those who did not.

The study was funded by Johnson & Johnson Consumer Companies, Inc., which said in a statement it was "committed to advancing clinical research on stress."

Dr. R. Dale McClure, president of the American Society for Reproductive Medicine says the study results were interesting.

"It's clear, based on this carefully designed study, that a holistic approach to infertility care leads to better outcomes for patients," he said.

But a second study presented at the ASRM meeting found that while complementary and alternative medical therapy was popular among couples getting infertility treatments, it did not make women any more likely to get pregnant.

A team at the University of California, San Francisco questioned 431 couples undergoing infertility therapy and found that 28 per cent had tried some kind of alternative medicine, mostly acupuncture or herbs, but they were not any more likely to achieve pregnancy.