Being stressed out may make it more difficult to become pregnant, new research suggests.The finding published in the journal Human Reproduction stems from an examination of how high levels of the stress-related enzyme alpha-amylase and the hormone cortisol affected the pregnancy process of about 400 women.All were between 18 and 40, and were married or in a committed relationship. None had a history of infertility and all had stopped using contraception in an effort to become pregnant. Each woman was tracked for up to 1 year between 2005 and 2009. Ultimately nearly 90% became pregnant and saliva analyses revealed that cortisol levels didn’t seem to affect the process.However, women whose alpha-amylase levels ranked in the top third took significantly longer to become pregnant than those with enzyme levels in the bottom third even after accounting for age, race, or alcohol, cigarette, and caffeine consumption. Similarly high enzyme levels also doubled the risk for infertility leading the investigators to conclude that stress reduction could be helpful for women seeking to become pregnant.I’m Dr. Cindy Haines of HealthDay TV with the news doctors are reading health news that matters to you.