Diabetes is a disorder in which the body
doesn't produce enough insulin (a hormone made by the pancreas that lets
the body turn blood sugar into energy or store it as fat), or can't use
insulin properly. In untreated diabetes, high levels of sugar can accumulate
in the blood and damage organs, including blood vessels, nerves, eyes
and kidneys. Some people with diabetes need daily insulin injections to
prevent these complications.
About 1 in 100 women of childbearing age has diabetes before pregnancy
(preexisting diabetes). Another 3 to 5 percent develop diabetes during
pregnancy (gestational diabetes). Today, most of these women can look
forward to having a healthy baby. While diabetes poses some risks in pregnancy,
advances in care have greatly improved the outlook for these pregnancies.
What risks does diabetes pose to the baby?
Women with poorly controlled preexisting diabetes in the early weeks
of pregnancy are two to four times more likely than nondiabetic women
to have a baby with a serious birth defect, such as a heart defect
or neural tube defect (NTD)¾ a birth defect of the brain or spinal
cord. They also are at increased risk of miscarriage and stillbirth.
Women with gestational diabetes, which generally develops later in
pregnancy, usually do not have an increased risk of having a baby with
a birth defect. However, some studies suggest that, if a woman's
gestational diabetes is severe enough to require treatment with insulin,
her baby may be at increased risk of birth defects. Some of these women
may have had unrecognized diabetes that began prior to pregnancy. They
may have had high blood sugar in the early weeks of pregnancy, which
increases the risk of birth defects.
Poorly controlled gestational diabetes also slightly increases the
risk of stillbirth. However, with improvements in medical care,
stillbirth is rare.
Women with poorly controlled diabetes (gestational or preexisting)
are at increased risk of having a very large baby (10 pounds or more).
Macrosomia is the medical term for this. These babies grow so large
because some of the extra sugar in the mother's blood crosses the placenta
and goes to the fetus. The fetus then produces extra insulin, which
helps it process the sugar and store it as fat. The fat tends to accumulate
around the shoulders and trunk, sometimes making these babies difficult
to deliver vaginally and putting them at risk for injuries during delivery.
During the newborn period, babies of all women with poorly controlled
diabetes are at increased risk of breathing difficulties, low blood
sugar levels and jaundice. These problems can be treated, but it's
better to prevent them by controlling blood sugar levels during pregnancy.
Babies of women with gestational diabetes also may be at increased risk
of developing obesity and diabetes as young adults.
Does diabetes cause other pregnancy complications?
With advances in medical care, women with diabetes are almost as likely
as women without diabetes to have an uncomplicated pregnancy and a healthy
baby, as long as blood sugar levels are well controlled beginning before
pregnancy. However, women with poorly controlled diabetes, especially
preexisting diabetes, are at increased risk of certain pregnancy complications.
These include miscarriage; pregnancy-related high blood pressure; polyhydramnios
(an excess of amniotic fluid, which can contribute to preterm labor);
preterm delivery; and stillbirth.
What tests are recommended to detect complications?
The doctor will carefully track the size and well-being of the
fetus, especially during the third trimester of pregnancy. He or she
may recommend one or more ultrasound examinations to assure that the
fetus is growing at a normal rate.
If the baby reaches a weight of 9 pounds, 14 ounces or more,
the doctor will likely recommend a cesarean delivery at term. The doctor
also may recommend a "nonstress test" (which may be repeated
weekly or more frequently), a procedure that monitors the baby's heart
rate.
In most cases, these tests will show that the pregnancy is progressing
normally. Although women with diabetes are at increased risk of cesarean
delivery, most have normal vaginal deliveries.
Why is pre-pregnancy care crucial for women with diabetes?
Women with preexisting diabetes should consult their doctors before
pregnancy to ensure that their blood sugar levels are well controlled.
This is important because the most serious birth defects
associated with diabetes originate in the early weeks of pregnancy,
before a woman may realize she is pregnant.
Studies have shown that blood sugar control begun before pregnancy largely
eliminates the extra risk of birth defects for women with preexisting
diabetes requiring insulin. Studies also show that blood sugar control
before and during pregnancy reduces the risk of miscarriage, stillbirth,
macrosomia and complications in the newborn period.
When a woman with diabetes plans to conceive, doctors often recommend
a monthly blood test that measures glycated hemoglobin (a substance
formed when glucose in the blood attaches to the protein in red blood
cells). This test shows how well blood sugar has been controlled during
the past two to three months. It can help determine when it is safest
to try to conceive. The test also may be used to monitor blood sugar
control during pregnancy.
All women should take a multivitamin containing 400 micrograms of the
B vitamin folic acid, as part of a healthy
diet, starting at least one month before pregnancy, to help prevent
NTDs. Women with preexisting diabetes are at increased
risk of having a baby with an NTD, so taking folic
acid may be especially crucial for them. At a preconception visit,
women with diabetes should ask their doctors whether they should take
a daily dose of folic acid greater than 400 micrograms. While there
are no studies on the use of such larger doses of folic acid to prevent
NTDs in women with preexisting diabetes, doses of 4,000 micrograms have
proven successful in reducing the risk of having another baby with an
NTD in women who already have had an affected baby.
Women with preexisting diabetes who take oral medications
to control their blood sugar levels will need to switch to insulin before
conceiving and during pregnancy, as the oral medications may pose a
risk of birth defects.
What are the symptoms of gestational diabetes and how is it detected?
Gestational diabetes is one of the most common pregnancy complications.
It usually develops during the second half of pregnancy, when hormones
or other factors interfere with the body's ability to use its insulin.
Most women with gestational diabetes have no symptoms, although some
may experience extreme thirst, hunger or fatigue. Blood sugar levels
generally return to normal after delivery.
Women at increased risk of gestational diabetes include:
those who are over age 30;
are obese;
have a family history of diabetes;
have had a very large (over 9½ pounds) baby;
or a stillborn baby
According to the Centers for Disease Control and Prevention (CDC),
gestational diabetes occurs more frequently in African-Americans, Hispanic/Latino
Americans, Pacific Islanders and American Indians than in other groups.
Most pregnant women are screened for gestational diabetes between
the 24th and 28th week of pregnancy.
Women who are considered at high risk (including women who have
had gestational diabetes in a previous pregnancy) often are screened
at an early prenatal visit and, if test results are normal, screened
again at 24 to 28 weeks.
According to the American Diabetes Association (ADA), women under
25 years of age, who have no other risk factors for diabetes, do
not require screening because they have a very low risk of the disorder.
The test involves taking a blood sample one hour after consuming
a drink of 50 grams of glucose (a form of sugar). Women with high
blood levels of glucose will take the similar, though longer, glucose
tolerance test, which involves drawing blood samples one, two and three
hours after drinking 100 grams of glucose.
Once gestational diabetes is diagnosed, most women can control
their blood sugar levels with diet and exercise.
What diet is recommended for pregnant women with diabetes?
A pregnant woman with either form of diabetes should follow a diet designed
especially for her. Most women with gestational diabetes are referred
to dietitians for this.
A woman with preexisting diabetes should already be following a special
diet, but she also should get nutritional counseling, as her diet
may need modifications as her pregnancy progresses.
How many calories a pregnant woman with diabetes should eat,
and the proportion of foods from the various food groups (i.e., fat,
carbohydrates, proteins, dairy, fruits and vegetables), depends upon
many factors, including weight, stage of pregnancy and baby's rate of
growth. Her doctor and dietitian use these factors, as well as her food
preferences, in designing a diet.
As a very general rule, a pregnant woman with diabetes
(gestational or preexisting) who is of average weight should consume
about 2,200 to 2,400 calories a day. This should help her gain
the recommended 25 to 35 pounds during pregnancy. For women with gestational
diabetes, this is divided among three meals and a bedtime snack.
Women with preexisting insulin- dependent diabetes often are advised
to eat one or two additional snacks. The dietitian will recommend
a diet that probably will include: 10 to 20 percent of calories from
protein (meat, poultry, fish, legumes); about 30 percent from fats
(with less than 10 percent from saturated fats); and the remainder
of calories from carbohydrates (bread, cereal, pasta, rice, fruits
and vegetables). A woman with diabetes also should limit sweets.
Should a pregnant woman with diabetes exercise?
Exercise can help control diabetes by prompting the body to use insulin
more efficiently, and is recommended for most women with gestational
diabetes and some women with preexisting diabetes. However,
pregnant women with diabetes always should talk to their doctors about
exercising. Pregnant women with poorly controlled diabetes or
certain complications, such as high blood pressure or blood vessel damage
(caused by preexisting diabetes), should exercise only upon the advice
of their health care provider.
Do pregnant women with diabetes require insulin treatment?
Many women with preexisting diabetes require insulin injections to keep
blood sugar levels under control. Insulin requirements change during
pregnancy, generally increasing after 20 to 24 weeks and stabilizing
by about 36 weeks.
Only about 10 to 15 percent of women with gestational diabetes require
insulin treatment. Insulin is recommended for the remainder of the
pregnancy if blood sugar levels do not stabilize after two weeks on
a special diet. However, a recent study found that women with gestational
diabetes who were treated with an oral diabetes medication called glyburide
did not have an increased risk of having a baby with birth defects,
compared to a similar group of women treated with insulin. Women treated
with the oral medication also did not have more pregnancy complications
than did women in the insulin-treated group. If results of this study
are confirmed, women with gestational diabetes that can't be controlled
by diet eventually may be able to take a pill instead of insulin injections.
(Because the women in the study received the drug after the first trimester,
the study does not demonstrate whether or not treatment would be safe
for women with preexisting diabetes, who require treatment early in
pregnancy.)
How can a pregnant woman monitor her diabetes at home?
Pregnant women who need insulin should monitor their
blood sugar levels several times a day. Many providers also advise
this for women with gestational diabetes controlled by diet. Blood glucose
meters or colored strips used with finger-stick devices make it easy
to check blood sugar levels and adjust insulin dosage between prenatal
visits.
The doctor may suggest a home urine test to measure levels of
ketones, weak acids produced when diabetes is poorly controlled and
the body burns fat instead of blood sugar for energy. Moderate to large
amounts of ketones in the urine can be a sign of ketoacidosis, a complication
that, unless promptly treated, can lead to death of the fetus.
Do women with diabetes require special care after delivery?
Some women with preexisting diabetes find that their blood sugar
levels may be more difficult to predict in the weeks after delivery.
This is especially true if a woman is breastfeeding.
Women with preexisting diabetes should monitor their blood
sugar levels frequently, so that they and their doctors can adjust
their insulin dose.
After delivery, blood sugar levels return to normal for most women
with gestational diabetes.
The ADA recommends that women who had gestational diabetes
have their blood sugar level checked 6 weeks after delivery to make
sure sugar levels are normal.
Women who have had gestational diabetes have about a 50 percent
chance of developing diabetes in the future, so the ADA also recommends
a blood sugar check every three years. These women can help reduce
their risk by starting a weight loss and exercise program after delivery.
They also face about a 50 percent risk of gestational diabetes
in another pregnancy. A recent study suggests that weight loss between
pregnancies also may reduce this risk.
For further information, contact: American Diabetes Association
1701 North Beauregard Street
Alexandria VA 22311
800/342-2383
Related
ArticlesWomen with poorly controlled preexisting diabetes in the early weeks of pregnancy are two to four times more likely than nondiabetic women to have a baby with a serious birth defect, such as a heart defect or neural tube defect (NTD)¾ a birth defect of the brain or spinal cord. They also are at increased risk of miscarriage and stillbirth.
With advances in medical care, women with diabetes are almost as likely as women without diabetes to have an uncomplicated pregnancy and a healthy baby, as long as blood sugar levels are well controlled beginning before pregnancy. However, women with poorly controlled diabetes, especially preexisting diabetes, are at increased risk of certain pregnancy complications. These include miscarriage; pregnancy-related high blood pressure; polyhydramnios (an excess of amniotic fluid, which can contribute to preterm labor); preterm delivery; and stillbirth.
