Everyday stress does not cause miscarriage. Studies have not found a link between miscarriage and the ordinary stresses and frustrations of modern life (like having a hard day at work or getting stuck in traffic). Likewise, being startled by a sudden loud noise does not cause a miscarriage.
Most causes of miscarriage are either unknown or beyond your control. More than half of miscarriages in the first trimester are thought to be random events caused by chromosomal abnormalities in the fertilized egg. This usually means that the egg or sperm had the wrong number of chromosomes, so the fertilized egg couldn't develop normally. (Read more about miscarriages and what might cause them.)
That said, extreme stress – from a divorce, severe financial problems, or the death of a close family member – can affect a developing baby's health. According to a 2008 Danish study of more than 19,000 pregnant women, those with a high level of psychological stress had an 80 percent greater risk of stillbirth than women who had an intermediate level of stress during pregnancy.
Other researchers have found that high stress levels can result in premature birth and low birth weight, and even lead to allergies and asthma later in life.
Find out ways to cope with anxiety and depression and stress during pregnancy.