Nearly one-third of all women who know they are pregnant will experience a miscarriage—and this number doesn't include the women will miscarry before they even know they are carrying a child, notes the Milton S. Hershey Medical Center at Penn State University. While the majority of miscarriages are unpreventable and caused by chromosomal or genetic defects, certain health and lifestyle factors have been linked to an increased risk of pregnancy loss.
pregnancies, chromosomal or genetic abnormalities are the most common cause of
miscarriage, accounting for more than half of all miscarriages, notes the
Center for Human Reproduction. These can be one-time, random events, or they
can be contributed to a genetic issue with the mother's or father's health
that, when unidentified, can cause repeated miscarriages.
A healthy fetus has 23 pairs of chromosomes – one set from the mother, and one
set from the father; an abnormal number of chromosomes or a defect in any one
of the 46 chromosomes can lead to miscarriage, typically in the first trimester.
Further testing would be necessary to rule out any inherited or genetic causes
or uterine abnormalities that could contribute to miscarriage.
If you have repeated miscarriages, your doctor may want to order karyotyping or
microarray testing, which looks for chromosomal abnormalities in a sample of of
cells taken from blood, bone marrow, or placental tissue. If you have a family
history of disease, you can undergo carrier genetic testing, which will
determine if your future children will be at an increased risk for a disease
such as sickle cell anemia or cystic fibrosis. More than 900 different types of
genetic tests currently exist and can cost anywhere from $100 to $2,000,
according to the National Human Genome Research Institute. So talk to your health
care provider about what types of genetic tests would be the most beneficial
for you and your partner.
Are You Over 35? Over 40?
The risk of
miscarriage associated with advanced maternal age– or, being pregnant over the
age of 35 – has been well documented, notes [Dr. Monica
Grover](http://medicalone.nyc/physicians.shtml), a family medicine physician
who specializes in women's health in New York.
"Advanced maternal age is a risk factor for a wide variety of conditions such
as infertility, pregnancy complications such as hypertension, congenital
abnormalities, and miscarriage," she says. "One of the reasons for this is
because miscarriages can be related to a chromosomal abnormality of an
ovulatory egg and the chances of these types of eggs increases with maternal
Additional research has shown that advanced paternal age, which refers to a
father who is 40 years old or more at the time of conception, is related to an
increased risk of marriage, Grover adds.
Manage Diabetes, Hypertension
that occur after the first trimester are more likely caused by a mother's
chronic health condition than a chromosomal abnormality, Grover points out.
"These conditions can include uncontrolled hypertension or diabetes,
auto-immune disorders such as lupus, hormonal disorders such as an underactive
or overactive thyroid, or even blood disorders such as sickle cell disease,"
Acute or chronic infections of the urinary tract or infections can lead to
later-term miscarriages, as can infections such as the measles, bacterial
vaginitis or cytomegalovirus, which can cause chickenpox, can all contribute to
pregnancy loss, she says. Ongoing management and treatment for these chronic
health conditions is critical during pregnancy.
Address Your Weight and Lifestyle Factors
underweight, overweight or obese can contribute to an increased risk for
pregnancy loss, Grover notes. "When adjusting for independent risk factors,
studies have shown that an underweight body mass index has a similar rate of
miscarriage of someone who is morbidly obese BMI," she explains.
The following BMI guidelines can help you determine this risk factor: *
Underweight: BMI of 18 or below * Overweight: BMI of 25 to 29.9 * Obese: BMI of
30 to 34 * Morbidly Obese: BMI of 35 or higher
In addition, caffeine intake, smoking, and the use of illicit drugs or alcohol
all have been linked to an increased risk of miscarriage. Smoking during
pregnancy has been shown to cause placental problems, preterm delivery, and
even stillbirth, the CDC notes, and a study published in the American Journal
of Epidemiology found that moderate consumption of alcohol during pregnancy –
on both the part of the mother and father – leads to an increased risk of
miscarriage during the first trimester.
You can reduce your risk of miscarriage from these controllable factors by
healthy eating, limiting caffeine, quitting smoking, and avoiding the use of
alcohol during pregnancy. Regular prenatal care from a qualified health care
provider is critical.
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