Voice of the Diabetic
Voice of the Diabetic
Back|
Next|
Table of Contents|
Home
EXPECTING THE BEST: DIABETES, PREGNANCY,
AND BLOOD GLUCOSE CONTROL
by Laura Hieronymus, RN, MSEd, CDE and
Patti Geil, MS, RD, LD, CDE
Pregnancy can be a special and exciting time in a woman's life.
The anticipation begins as soon as you hear the words: “You're expecting
a baby.” Once you've gotten used to the amazing news, you may wonder about
such things as whether the baby will be a boy or a girl, when the baby is due,
and, perhaps most important, what you need to do in the meantime to make sure
the baby stays healthy and develops normally.
All women feel a certain amount of anxiety and sometimes even
fear about how pregnancy will affect them, and whether their baby will be healthy
and normal. Women with diabetes are no different, but they do have one more
thing to be concerned about: maintaining control of blood glucose levels. This
is true whether a woman has type 1 or type 2 diabetes before becoming pregnant,
or whether she is diagnosed with a condition called gestational diabetes during
pregnancy. The good news is that if a woman who has diabetes (of any type) learns
as much as she can about managing her blood glucose, and puts that knowledge
into practice, she can have a healthy pregnancy and a healthy baby.
Blood glucose control essential
Optimal blood glucose control is important throughout pregnancy, both for the
mother's health and the baby's. Glucose in a mother's blood crosses the placenta
to her baby, affecting the baby's blood glucose level. (The placenta, a flat
circular organ, links the unborn baby to the mother's uterus, to provide oxygen,
nutrients, and the elimination of wastes.) The baby begins making its own insulin
around 13 weeks gestation. If the baby is constantly exposed to high levels
of glucose, it is as if the baby were overeating: The baby produces more insulin
to absorb the excess glucose, resulting in weight gain and an increase in size.
Under these conditions, the baby can become too large, a condition known as
macrosomia. Macrosomia is associated with difficult vaginal delivery, which
can lead to birth injury and/or asphyxia, a condition in which the baby doesn't
get enough oxygen.
Another reason that blood glucose control is important right
up to the day of delivery is that if an unborn baby has high levels of insulin
on a consistent basis, or if the mother's blood glucose level is high during
labor, the baby may experience hypoglycemia (low blood sugar) or other complications
when the umbilical cord (and the maternal blood supply) is cut.
The details of managing blood glucose levels during pregnancy
may be different for women who already have either type 1 or type 2 diabetes
before pregnancy and for those who are diagnosed with diabetes during pregnancy,
or gestational diabetes. (These differences are covered later in this article.)
The recommended blood glucose goals, however, are the same.
It is important to note that the blood glucose goals suggested
by the American Diabetes Association (ADA) for pregnant women are lower than
those for the general population with diabetes. (See sidebar: “Blood Glucose
Goals During Pregnancy.”) In addition, the ADA suggests that pregnant women
check their blood glucose levels up to eight times per day: once before each
meal, again one hour after each meal, at bedtime, and once in the middle of
the night. (Any woman who is taking insulin or certain kinds of blood glucose-lowering
pills would need to do additional checks before driving, and if she experienced
any symptoms of low blood sugar.) Your health-care team may recommend a somewhat
different monitoring schedule depending on the type of diabetes you have and
how you treat it. However, frequent self-monitoring is needed to ensure that
blood glucose levels remain within the recommended range.
In addition to blood glucose monitoring, daily urine ketone testing is often
advised for pregnant women with diabetes. Ketones are acid substances that collect
in the bloodstream if the body is unable to break down glucose for energy. This
can occur if there is not enough insulin to break down glucose in the bloodstream
or if there is not enough glucose available to meet energy needs. In either
case, the body begins to use stored fat for energy, a process that yields the
acidic byproducts called ketones. If the body is unable to get rid of the ketones
fast enough (via the lungs and urine), they build up, and can cause a potentially
deadly condition called ketoacidosis.
Ketones in the blood during pregnancy are associated with decreased
intelligence in the baby, and an episode of ketoacidosis during pregnancy greatly
increases the risk of the fetus dying in the uterus. Diabetic ketoacidosis may
develop rapidly, and at lower blood glucose levels in women who are pregnant
than in those who are not. The best approach for preventing this outcome is
to closely monitor blood glucose levels outside the recommended range for pregnancy,
and to promptly treat elevated blood glucose levels, as directed by your diabetes
management team. Notify your diabetes health-care team immediately if you detect
ketones in your urine and have a high blood glucose level.
Ketones that occur when there isn't enough glucose in the bloodstream
are called “starvation ketones.” They may occur in women with gestational
diabetes, as well as in those with type 1 or type 2 diabetes. A woman with starvation
ketones would typically have a blood glucose reading in the normal range or
lower than normal. If you are getting starvation ketones, your medical team
may advise you to increase the amount of calories and carbohydrate in your meals
and snacks.
During your pregnancy, if you are not already seeing an endocrinologist,
your obstetrician may refer you to one. Most likely, you would see the endocrinologist
at least once a month during the first and second trimesters (approximately
the first six months of pregnancy) and every two weeks in the third trimester
(the last three months). In addition to your scheduled appointments, you should
discuss specific guidelines for prompt follow-up if blood glucose levels are
not staying within recommended ranges. Your obstetrician will likely evaluate
the growth and condition of your baby throughout your pregnancy with tests such
as ultrasound to monitor your baby's size and the non-stress test, which measures
a baby's heart rate in response to his or her own movements. Additional testing
to monitor your baby's health, or yours, may be recommended by your obstetrician
or by members of your diabetes health-care team.
Insulin needs during pregnancy
During any pregnancy, a woman's insulin needs change, because
the normal hormone production and weight gain that occur during pregnancy increase
insulin resistance. (See sidebar: “Insulin Requirements During Pregnancy.”)
In women who do not have or develop diabetes, blood glucose levels remain stable
because the pancreas is able to produce more insulin to accommodate the increased
demand. In women with preexisting diabetes, or who develop gestational diabetes,
the pancreas cannot keep up with the increased demand, so blood glucose levels
rise unless steps are taken to lower them.
In women with preexisting diabetes, insulin needs during the
first several weeks of pregnancy are not usually that different from those before
conception. However, in the latter part of the first trimester, women with preexisting
diabetes may have a higher risk of hypoglycemia because of an increase in sensitivity
to insulin, rapid fetal growth, and a reduction in eating associated with “morning
sickness.” Around the 16th week of pregnancy, insulin needs gradually increase,
due to increasing levels of hormones, including human placental lactogen (hPL),
a form of “growth hormone” for the baby.
All women with type 1 diabetes, and most with type 2 either
inject or infuse insulin during pregnancy. Women with gestational diabetes also
have to take steps to control their blood insulin level, but not all will have
to inject insulin. Some women with gestational diabetes can keep their blood
glucose at recommended levels with changes in diet and moderate exercise. Many,
however, must eventually use insulin.
Control before conception
In women with type 1 or type 2 diabetes, optimal blood glucose
control is essential prior to conception, because it is hard to be absolutely
certain of when conception takes place. The incidence of fetal malformations
is reduced significantly in women who have near-normal glycosylated hemoglobin
(HbA1c) levels before they become pregnant. The rate of miscarriage in women
with preexisting diabetes is also reduced by keeping blood glucose as close
to normal as possible in the first trimester.
Ideally, you should strive for a near-normal HbA1c test result at least three
months prior to pregnancy. It is important to discuss any plans to become pregnant
with your diabetes health-care team, particularly if you have vascular complications
related to your diabetes, such as eye or kidney disease. In this situation,
pregnancy is a potential risk to your health. For women with no vascular complications,
a thorough physical exam, good nutrition (including a folic acid supplement),
and excellent blood glucose control before you become pregnant will help minimize
any health risks to you and your baby. Be sure you are using a reliable method
of birth control, as you work toward optimal blood glucose levels.
Gestational diabetes
Gestational diabetes is a form of glucose intolerance (difficulty
metabolizing blood glucose) that is first recognized during pregnancy. It affects
almost 7% of all pregnancies. Factors that may contribute to a high risk of
gestational diabetes include overweight, a history of gestational diabetes with
a prior pregnancy, GLYCOSURIA (glucose in the urine, which would be found in
a routine urine test) and a strong family history of diabetes. In addition,
women who are African-American, Hispanic, or from certain Native American groups,
as well as women with polycistic ovary syndrome (PCOS) have shown a higher risk
for gestational diabetes.
Screening tests should be recommended between 24 and 28 weeks
gestation for any woman considered at risk of gestational diabetes by her obstetrician.
These tests usually involve drinking a pre-measured glucose solution, and then
having blood samples drawn and checked for glucose level, to determine if the
body tolerates the glucose load normally. Test levels that are out of the normal
range may indicate that the mother's blood glucose levels are likely to rise
as the pregnancy progresses.
If you are diagnosed with gestational diabetes, your obstetrician
may refer you to a diabetes educator or to an endocrinologist (or both), for
help managing your diabetes and your pregnancy. Because blood glucose control
is essential during pregnancy, weekly follow-ups with the health professional
managing your diabetes are usually recommended.
Most cases of gestational diabetes disappear after delivery
because two of the primary factors that contribute to insulin resistance and
high blood glucose levels are either diminished (the extra weight gained during
pregnancy) or gone (the hormones produced by the placenta). If your blood glucose
levels were normal prior to the pregnancy, they will most likely return to normal
after delivery. However, once you have had gestational diabetes, you are likely
to develop it again in another pregnancy. You also face a greater risk for developing
type 2 diabetes later in life.
Tools for control
The tools used to maintain blood glucose control during pregnancy
are the same tools used to control any case of diabetes. They include a meal
plan, an exercise plan, and possibly an insulin plan.
Meal plan. Whether you have preexisting diabetes or gestational diabetes, you
should work with a registered dietitian to design an individualized meal plan
for your pregnancy. The plan should focus on foods that provide good nutrition
for you and your baby, and that help keep your blood glucose level in the desired
range. Because carbohydrate has the most immediate impact on blood glucose levels,
your meal plan should specify how much carbohydrate to eat and when to eat it.
Carbohydrate is found mainly in foods such as breads, cereals, pasta, starchy
vegetables, fruits, and sweets. Frequent blood glucose monitoring will help
you determine the appropriate amount and timing of carbohydrate.
Your dietitian can also suggest how many calories you need each
day based on your recommended weight gain. The amount of weight you should gain
during pregnancy depends on your weight before pregnancy. In general, a woman
at a healthy weight before pregnancy should gain 25 to 35 pounds during her
pregnancy. Your health-care team may advise you to gain more if you are underweight,
or less, if you are overweight. Keep in mind, however, that pregnancy is definitely
not a time to try to lose weight. Most mothers require about 100 extra calories
per day during the first trimester and an additional 300 calories per day during
the remainder of the pregnancy to ensure the ideal weight gain for the mother
and birth weight for the baby. (See sidebar: “Weight Gain During Pregnancy,”
which illustrates how pregnancy weight gain is distributed.)
In most cases, your dietitian will recommend that you eat three
meals a day with two to four between-meal snacks. An evening snack is particularly
important to prevent hypoglycemia during the night and urine ketones or nausea
in the morning.
You may be concerned about the safety of consuming sugar substitutes
during pregnancy. At this time, research shows that the four most commonly used
sugar substitutes (acesulfame-K, aspartame, saccharin, and sucralose) are safe
to use in moderation during pregnancy. Some of these sweeteners do cross the
placenta, and can reach the baby, but there is no evidence they cause ill effects.
If in doubt, follow the advice of your obstetrician.
For more specifics on the components of a well-balanced diet
during pregnancy, see sidebar: “Eating for Two.”
Physical Activity
Regular physical activity is essential to diabetes control and
to general health and well-being Your health-care team can help you determine
a safe level of exercise for you during pregnancy. If you have always exercised
in the past, you may be able to continue to exercise at a more moderate level
while you are pregnant. If exercise was not part of your pre-pregnancy routine,
check with both your obstetrician and endocrinologist before you start, and
choose an activity such as brisk walking or swimming, to incorporate into your
daily routine. Because exercise usually lowers blood glucose, be alert to the
symptoms of hypoglycemia, and check your blood glucose level before and after
you exercise.
Insulin management. Insulin is the most common medicine used
for blood glucose control during pregnancy. Blood glucose-lowering pills are
used much less often because of a lack of data on their safety. However, at
least one recent study concluded that glyburide (brand names DiaBeta, Glynase
PresTab or Micronase), when taken by women with gestational diabetes during
the last six months of pregnancy, did not change fetal outcome.
Women with type 1 diabetes may prefer to stick with their usual
insulin delivery method during pregnancy, or they may decide to try something
new, such as insulin pump therapy. For some, using a pump during pregnancy allows
them to fine-tune their insulin requirements.
Women with type 2 diabetes who take pills as part of their diabetes
treatment plan are usually advised to switch to insulin during pregnancy. In
fact, many health care practitioners recommend that women with type 2 diabetes
switch to insulin therapy before becoming pregnant. This may help them adjust
to insulin therapy and possibly allow them to bring their blood glucose levels
into the ranges recommended during pregnancy before they become pregnant.
As mentioned earlier, women with gestational diabetes usually
start by seeing how well dietary changes control their blood glucose levels,
and then add insulin if blood glucose levels do not stay within recommended
ranges. Women who must learn to use insulin because of gestational diabetes
may find that using an insulin pen is easier than using a syringe. Using premixed
insulins, rather than mixing your own, may also simplify your diabetes management.
The most common side effect of insulin therapy is hypoglycemia.
Once insulin enters the body and begins working, blood glucose levels may drop
lower than recommended if you do not eat to balance the effects, or if you exercise
too much. Women using insulin during pregnancy should make sure they receive
information about the warning signs and treatment of hypoglycemia. In addition,
they should be aware that hypoglycemia unawareness (the inability to detect
early signs of low blood glucose) may be more common in pregnant women, especially
those with type 1 diabetes.
Labor and Delivery
Most physicians prefer that women with diabetes deliver as close to their due
date as possible. Babies delivered after their due date tend to be larger and
risk more complications. If natural labor is not timely, and a woman plans to
deliver vaginally, a hormone called oxytocin can be given, usually intravenously,
to induce labor. If a woman is scheduled for caesarian section, oxytocin is
not necessary.
Many women with diabetes are able to deliver vaginally. A caesarian
section may be needed if the baby is too large (macrosomic), if the woman's
pelvis is too small, or if a woman has vascular complications or blood pressure
problems. A caesarian delivery may also be required if a baby is in the breech
position (when the baby's feet or buttocks enter the birth canal first).
Labor is an intense, active process, which can lower a woman's
blood glucose level. A caesarian delivery, on the other hand, may raise a woman's
blood glucose level, because the surgical procedure is a stress on the body.
If you have type 1 or type 2 diabetes, your doctor may have you on insulin intravenously
during labor and delivery. The IV apparatus continuously infuses quick-acting
insulin, and may allow for smoother blood glucose control, since adjustments
can be made as necessary. The goal is to keep blood glucose levels as normal
as possible to prevent hypoglycemia in your newborn. Most women with gestational
diabetes do not require any insulin during the labor and delivery process. After
delivery, continuing to maintain blood sugar levels in a near-normal range facilitates
the healing process.
Recovery
If you have type 1 or type 2 diabetes, your insulin requirements
may return to what they were before your pregnancy within a few weeks of delivery.
Check your blood glucose levels frequently, and make adjustments to your insulin
dosage as needed.
If you had gestational diabetes, it is likely that your blood
glucose level will return to normal almost immediately after your baby is born.
But since gestational diabetes puts you at increased risk for developing type
2 diabetes in the future, you should have your blood glucose level measured
at your first postpartum checkup (usually four to six weeks after delivery)
and yearly thereafter. To minimize your risk of developing type 2 diabetes,
eat a balanced diet, exercise regularly, and keep your weight at a reasonable
level.
Breast-feeding
Diabetes is no barrier to breast-feeding. Breast milk provides the ideal source
of nutrition for babies, as well as antibodies that fight certain infections.
Breast-feeding also promotes weight loss in the mother, may help protect the baby
from developing diabetes in the future, and may help to establish a special mother-baby
bond.
If you decide to breast-feed, speak with a registered dietitian
about the foods you need to ea , so you will get enough calcium, fluids, and
protein. Breast-feeding increases a woman's caloric needs, and, because it takes
energy, may increase her risk of hypoglycemia. Episodes of hypoglycemia are
more likely to occur within an hour after breast-feeding, so this is an important
time to check your blood glucose level. Napping after meals and snacks is also
recommended to lower the risk of hypoglycemia. You may need to adjust your insulin
dosage, particularly overnight, to prevent your blood glucose level from dropping
during late-night feedings.
Women with type 2 diabetes who switched from oral pills to insulin
during pregnancy are generally encouraged to stay on insulin for at least a
month after delivery. For many of the newer diabetes drugs, little or no research
has been done on their use in breast-feeding women.
Tough job, big rewards
Managing your diabetes during pregnancy means paying extra attention
to your lifestyle during these important months. Though you may feel overwhelmed
at times, your health-care team is available to answer your questions and help
you attain excellent blood glucose control. The commitment you make now will
pay off with the best results in the future: a healthy, happy baby, and a healthy
you.
Laura Hieronymus and Patti Geil are Certified Diabetes Educators
in an ADA-recognized education service in Lexington, Kentucky. They counsel
in the area of diabetes and pregnancy management, with Kristina Humphries, MD.
Reprinted with permission from DIABETES SELF-MANAGEMENT. Copyright ©2001,
R.A. Rapaport Publishing, Inc. For subscription information, call: 1-800-234-0923.
SIDEBARS: WEIGHT GAIN DURING PREGNANCY
Ever wonder why pregnancy usually involves gaining at least
25 pounds, when a baby usually weighs only 7 or 8? Here's a breakdown of what
accounts for the other 17 or more pounds
WHAT POUNDS
__________________________________________
Developing
unborn baby 7-8
__________________________________________
Placenta 1-2
__________________________________________
Amniotic fluid 2
__________________________________________
Uterus 2
__________________________________________
Increase in
blood volume 3
__________________________________________
Breasts 1
__________________________________________
Body fat 5 or more
__________________________________________
Increased muscle
tissue and fluid 4-7
__________________________________________
TOTAL: 25 or more
__________________________________________
BLOOD GLUCOSE GOALS DURING PREGNANCY
The American Diabetes Association's recommended goals for blood
glucose during pregnancy are even closer to the normal non-diabetic range than
for the general population with diabetes. These goals have been set with the
health of both mother and developing baby in mind.
WHEN WHOLE BLOOD PLASMA VALUE
Fasting 60-90 Mg/dl 69-104 Mg/dl
Before meals 60-105 Mg/dl 69-121 Mg/dl
1 hour after meals
100-120 Mg/dl 115-138 Mg/dl
2 AM-6 AM 60-120 Mg/dl 69-138 Mg/dl
MORE READING ON PREGNANCY
For more information on diabetes and pregnancy, you may find
the following resources helpful.
Books
Books published by the American Diabetes Association can be
purchased via the Internet (http://store.diabetes.org/adabooks)
Or by calling, toll-free: 1-800-232-6733.
DIABETES AND PREGNANCY: WHAT TO EXPECT (2000) American Diabetes
Association
GESTATIONAL DIABETES: WHAT TO EXPECT (2000) American Diabetes
Association
Brochures
These brochures can be read online, or ordered by phone, using
the toll-free numbers listed below.
DIABETES AND PREGNANCY, Juvenile Diabetes Research Foundation,
telephone: 1-800-533-2873; website: www.jdf.org/jdfliving/pages/pregnancy.html
UNDERSTANDING GESTATIONAL DIABETES: A Practical Guide to a Healthy
Pregnancy, National Institute of Child Health and Human Development; telephone:
1-800-370-2943; website: www.nichd.nih.gov/publications/pubs/gesttoc.htm
EATING FOR TWO
Eating enough of the right foods is one of the most important
things you can do to ensure your baby is healthy. Although nutrient needs increase
during pregnancy, most women can meet these needs by eating a balanced diet
that includes a variety of foods. However, for some women, prenatal vitamin
and mineral supplements, particularly iron, may be necessary. When planning
your meals during pregnancy, pay special attention to the following nutrients:
Protein
Pregnant women require an extra 10 grams of protein daily (or a total of 60
grams daily) for a healthy baby and placenta. A three-ounce serving of meat
provides approximately 20 grams of protein.
B Vitamins
The requirements for B vitamins increase during pregnancy; B
vitamins help to metabolize the energy from food and help protein to make new
body cells. Getting adequate amounts of a B vitamin called folate, or folic
acid, is particularly important in the first three months of pregnancy. Consuming
enough folate before pregnancy and in the early stages may lower the risk of
neural tube birth defects (birth defects that involve the spinal column) in
the baby. Pregnant women require 600 micrograms of folate daily. A half-cup
serving of boiled navy beans provides 125 micrograms of folate.
Calcium
Calcium is critical for preserving a mother's bone mass while
the baby's skeleton develops. Pregnant women need 1,000 milligrams of calcium
daily. An eight-ounce glass of milk provides 300 milligrams of calcium.
Iron
Iron is essential in making hemoglobin, a blood component that
carries oxygen through the body to the placenta. It can be difficult to get
enough iron in the diet because it is not well absorbed from food, and many
women start pregnancy with low iron stores. Pregnant women require 27 milligrams
of iron daily. A three-ounce serving of lean beef has almost 3 milligrams of
iron.
Back to Top
Share a Comment