Pregnant women who are stressed out during
the first three weeks after conception are nearly three
times as likely to miscarry, a new study finds.
"Try to provide yourself with what you consider
a good environment. The less stress, the better,"
advised lead researcher Pablo Nepomnaschy, a postdoctoral
fellow at the National Institute of Environmental Health
Sciences of the National Institutes
of Health in Research Triangle Park, N.C.
His team published its findings in this week's issue
of the Proceedings of the National
Academy of Sciences.
The NIH team evaluated 61 women over 12 months, collecting
each woman's urine three times a week to check for pregnancy
status and levels of cortisol, a stress-linked hormone.
"This study is special in the sense that we include
cortisol data," said Nepomnaschy, He added that they
did this testing very early in the pregnancy because "most
pregnancy losses take place in the first three to four
weeks after conception."
Of the 61 women, 22 got pregnant. Nine carried to term
and 13 miscarried. Women with increased cortisol levels
during the first three weeks of pregnancy were 2.7 times
more likely to miscarry, the researchers found.
In all, miscarriages occurred in 90 percent of pregnancies
in which the women had increased cortisol levels and in
33 percent of those with normal cortisol levels.
Nepomnaschy said it's unclear why a boost in cortisol
might raise miscarriage risks, but he offered a hypothesis:
"The body might interpret that [increased cortisol
level] as conditions deteriorating, and maybe that might
trigger an abortion mechanism."
The women studied were all residents of a rural area
of Guatemala. "This population is more alike than
any population in the United States," Nepomnaschy
said, explaining that he was trying to get a sample of
women who were similar in lifestyle, ethnicity and culture
to rule out other factors linked to miscarriage. The women
studied had similar diets and activity levels, and were
all of the same ethnicity.
Another expert, Dr. Mary Stephenson, an obstetrician-gynecologist
who runs the Recurrent Pregnancy Loss Program at the University
of Chicago, said, "It's an intriguing article. Certainly
more research is needed. But it is a potential mechanism
by which miscarriage may occur."
Other studies have looked at the cortisol/miscarriage
link, Stephenson said. "The results have been conflicting.
There are some studies in animals that suggest that stress
increased the risk of miscarriage. And doctors have long
suspected that stress does the same in people."
About 15 percent of recognized pregnancies end in miscarriage,
according to the March of Dimes. But Stephenson said that
statistic usually includes pregnancies that made it to
six weeks. "When you count the ones that occur before
six weeks, up to half of pregnancies end in miscarriage,"
she noted.
The best advice for women trying to get pregnant is to
de-stress your life before you conceive, she said.
"I talk about this a lot with my patients,"
Stephenson said. "I recommend that before they get
pregnant, they take a serious look at their lifestyle."
And that includes getting enough sleep, so fatigue isn't
an issue. "Fatigue is a type of stress," Stephenson
said.
