Topic Overview
What is pre-eclampsia?
Pre-eclampsia is
new high blood pressure after 20 weeks of pregnancy. It usually goes away after you give birth.
Not all high blood pressure is pre-eclampsia. In some women, blood pressure goes up very high in the second or third trimester. This is sometimes called gestational hypertension, and it can lead to pre-eclampsia.
Pre-eclampsia can be dangerous for the mother and baby. It can
keep the baby from getting enough blood and oxygen. It also can harm the
mother's
liver,
kidneys, and brain. Women with very bad pre-eclampsia
can have dangerous seizures. This is called
eclampsia.
What causes pre-eclampsia?
Experts don't know the exact cause.
Pre-eclampsia seems to start because the
placenta doesn't grow the usual network of blood vessels deep in the wall of
the uterus. This leads to poor blood flow in the
placenta.
If your mother had
pre-eclampsia while she was pregnant with you, you have a higher chance of
getting it during pregnancy. You also have a higher chance of getting it if the
mother of your baby's father had pre-eclampsia.
Already having high blood pressure when you
get pregnant raises your chance of getting pre-eclampsia.
What are the symptoms?
Mild
pre-eclampsia usually doesn't cause symptoms.
But pre-eclampsia can cause
rapid weight gain and sudden swelling of the hands and face.
Severe
pre-eclampsia causes symptoms such as a very bad headache and
trouble seeing and breathing. It also can cause belly pain and decreased
urination.
How is pre-eclampsia diagnosed?
Pre-eclampsia is usually found during a prenatal
visit.
This is one reason why it's so important to go to all of your prenatal
visits. You need to have your blood pressure checked often. During these
visits, your blood pressure is measured. A sudden increase in blood pressure often is the first
sign of a problem.
You also will have a urine test to look for
protein, another sign of pre-eclampsia.
If you have high blood
pressure, tell your doctor right away if you have a headache or belly pain.
These signs of pre-eclampsia can occur before protein shows up in your
urine.
How is it treated?
The only cure for pre-eclampsia is having the baby.
You may get medicines
to lower your blood pressure and to prevent seizures.
You also may get medicine
to help your baby's lungs get ready for birth.
Your doctor will try to deliver
your baby when the baby has grown enough to be ready for birth. But sometimes a
baby has to be delivered early to protect the health of the mother or the baby.
If this happens, your baby will get special care for premature babies.
Frequently Asked Questions
Learning about pre-eclampsia: | |
Being diagnosed: | |
Getting treatment: | |
Ongoing concerns: | |
Cause
Experts don't know the exact cause of
pre-eclampsia.
But it may start with a poorly developed
placenta that doesn't circulate blood normally. What causes this placenta problem isn't yet clear. Experts also don't know why the
mother's body then develops high blood pressure.
Immune system response
Pre-eclampsia
occurs most often in women who are pregnant for the first time and in women who
have been pregnant before but now have a first pregnancy with a different man.
Exposure to an
antigen from the father (in the growing
placenta or fetus, for example) may trigger an immune
response in the woman's body. This immune response—the body's way of fighting infection—may result in narrowing of
the blood vessels throughout the body, causing higher blood pressure and other
problems.
Symptoms
Although you may have other symptoms, you will not be
diagnosed with pre-eclampsia unless you also have one or both of the following:
- Your blood pressure is high.
- A urine test shows that you have too much protein in your urine.
- You have other problems related to pre-eclampsia.
Other symptoms of mild pre-eclampsia may include:
- Swelling of the hands and face that doesn't
go away during the day. (If you have no other symptoms of
pre-eclampsia, this swelling is probably a sign of normal
pregnancy.)
- Rapid weight gain—more than
1 kg (2 lb) a week or
3 kg (6 lb) a
month.
- Bleeding from a cut or injury that lasts longer than
usual.
Severe pre-eclampsia
In severe pre-eclampsia,
systolic blood pressure is over 160, or diastolic blood pressure is over
110, or both.
As blood circulation
to the organs decreases, more severe symptoms can develop, including:
- A severe headache that will not go away
with medicine such as acetaminophen.
- Blurred or dimming vision,
spots in the visual field, or periods of blindness.
- Decreased
urination—less than
500 mL (2 cups) in 24
hours.
- Lasting belly pain or tenderness, especially on the
upper right side.
- Problems breathing, especially when lying
flat.
- HELLP syndrome. This is a life-threatening liver disorder.
It is usually related to pre-eclampsia. Get emergency medical treatment if you
have several symptoms of HELLP syndrome, such as headaches, vision problems, fatigue, or belly pain.
Eclampsia
When pre-eclampsia leads to
seizures, it is
called
eclampsia.
Eclampsia is life-threatening for both a
mother and her baby. During a seizure, the oxygen supply to the baby is
drastically reduced.
Call 911 any time a pregnant woman has a
seizure.
What Happens
Pre-eclampsia can be mild or
severe. It may get worse gradually or rapidly. It affects your blood
pressure,
placenta,
liver, blood,
kidneys, and brain.
It's very important to get treatment, because both you and your baby could suffer life-threatening problems involving your:
- Blood pressure. The blood vessels increase their resistance
against blood flow, increasing blood pressure. Very high blood pressure keeps your baby from getting enough blood and oxygen. Also, blood
volume doesn't increase as much as it should during pregnancy. This can affect
the baby's growth and well-being.
- Placenta. The blood vessels of the placenta don't grow deep
into the uterus as they should. And they don't widen as they normally would. This
makes them unable to provide normal blood flow to the baby.
- Liver. Poor blood flow to the mother's liver can cause liver
damage. Liver impairment is related to the life-threatening
HELLP syndrome, which requires emergency medical treatment.
- Kidneys. When affected by
pre-eclampsia, the kidneys can't work as well as they should to remove waste and extra water.
- Brain. Vision impairment,
persistent headaches, and seizures (eclampsia) can develop. Eclampsia can lead to maternal coma and fetal and maternal death. This is why
women with pre-eclampsia are often given medicine to prevent
eclampsia.
- Blood. Low
platelet levels in the blood are common with
pre-eclampsia. In rare cases, a potentially life-threatening blood-clotting and
bleeding problem develops along with severe pre-eclampsia.1 This condition is called disseminated intravascular
coagulation (DIC). After delivery, DIC goes away. In the meantime, you may be
given a medicine (clotting factor), blood transfusion, or platelet transfusion.
Delivery of the baby and placenta is the only "cure"
for pre-eclampsia. If your condition becomes dangerous enough that delivery is
necessary but you don't go into labour, your doctor will induce labour or
deliver the baby with surgery (caesarean section).
Unless you have
chronic high blood pressure, your blood pressure should return to normal in a
few days or weeks. In severe cases, this can take 6 or more weeks.
The infant
The earlier in the pregnancy that
pre-eclampsia begins and the more severe it becomes, the greater
the risk of preterm birth, which can cause problems for the newborn.
An infant born before
37 weeks may have difficulty breathing because of immature lungs (respiratory distress syndrome).
A newborn affected by
pre-eclampsia may also be smaller than normal.
This is because of inadequate nutrition from poor blood flow through the
placenta.
What Increases Your Risk
Risk factors (things that increase your risk) for pre-eclampsia include:
- Chronic (ongoing) high blood pressure, chronic kidney disease, or diabetes.
- High blood pressure in a past
pregnancy, especially before week 34.
- Personal history of
pre-eclampsia.
- Family history of pre-eclampsia.
- Being very overweight
at the time of conception.
- Being pregnant with more than one baby (such as twins
or triplets).
- First pregnancy ever or first-time pregnancy with
current partner.
- Age younger than 21 or older than
35.
When To Call a Doctor
Someone
must call 911 or other emergency services immediately if you are having a seizure (eclampsia). Eclampsia can lead to a
coma. It is life-threatening to both you and your baby.
If you are pregnant and have pre-eclampsia, your
family and friends should know
how to help during a seizure.
Seek medical care immediately
if you are pregnant and begin to have symptoms of pre-eclampsia, such as:
- Blurred vision or other vision
problems.
- Frequent headaches that are becoming worse or a
persistent headache that does not respond to non-prescription pain
medicine.
- Pain or tenderness in your belly, especially in the
upper right section.
- Weight gain of
1 kg (2 lb) or more over a
24-hour period.
- Shoulder, neck, and other upper body pain (this pain starts
in the liver).
If you have mild high blood pressure or mild pre-eclampsia,
you may not have any symptoms. It is important to see a health professional
regularly throughout your pregnancy.
Symptoms such as heartburn or swelling in the legs
and feet are normal during pregnancy. They usually aren't symptoms of
pre-eclampsia. You can discuss these symptoms with your doctor or midwife
at your next scheduled prenatal visit. But if swelling occurs along with other
symptoms of pre-eclampsia, contact your doctor right away.
Who to see
Your family doctor, general practitioner, or midwife can treat high blood pressure and pre-eclampsia during pregnancy. You may be referred to an obstetrician or a perinatologist.
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Examinations and Tests
Pre-eclampsia is usually found during regular
prenatal checkups.
Routine prenatal tests
Certain tests are given at
each prenatal visit to check for pre-eclampsia. These
include a:
- Blood pressure reading. Blood pressure is always monitored closely during pregnancy.
- Urine test to check for too much protein in the
urine. This is a sign of kidney damage caused by pre-eclampsia.
- Weight
measurement. Rapid weight gain can be a sign of pre-eclampsia.
Tests for women considered high-risk for pre-eclampsia
Other tests may also be used to check for signs of
pre-eclampsia, including:
- Blood tests to check for problems such as HELLP syndrome and kidney damage.
(Too much uric acid in the blood is often the earliest sign of
pre-eclampsia.)
- Creatinine clearance test to check kidney
function. This
requires both a blood sample and a 24-hour urine collection.
- 24-hour urine collection test to check protein in the
urine.
Tests for women who have pre-eclampsia
If results from
one or more of the above tests suggest that you have pre-eclampsia, you and your
baby will be closely monitored for the rest of your pregnancy.
Testing is more frequent and extensive when pre-eclampsia is severe and
the pregnancy is far from full-term (less than 36 weeks).
You may have a physical examination to check for signs that pre-eclampsia is getting worse.
You may also have:
- Blood tests to check for blood abnormalities
and kidney damage.
- A creatinine clearance test.
Tests for women who have eclampsia
If you have a
seizure (eclampsia), one or more of the following tests may be
done after delivery:
Tests for the baby
If you get pre-eclampsia, the baby's health also will be closely
watched. The more severe your condition, the more often you'll need testing,
ranging from once a week to daily.
Tests commonly used include:
Less often,
amniocentesis is used to check fetal well-being if
preterm delivery is being considered. The test shows whether the baby's lungs are mature enough for birth.
Treatment Overview
Mild pre-eclampsia
For mild pre-eclampsia that is not rapidly
getting worse, you may only have to reduce your level of activity, monitor how
you feel, and have frequent office visits and testing.
Moderate to severe pre-eclampsia
For moderate or severe pre-eclampsia, or for pre-eclampsia
that is rapidly getting worse, you may need to go to the hospital for
expectant management. This typically includes bedrest,
medicine, and close monitoring of you and your baby.
Severe pre-eclampsia or an
eclamptic seizure is treated with
magnesium sulfate. This medicine can stop a seizure
and can prevent seizures. If you are near delivery or have severe pre-eclampsia,
your doctor will plan to deliver your baby as soon as possible.
Life-threatening pre-eclampsia
If
your condition becomes life-threatening to you or your baby, the only treatment options are magnesium sulfate
to prevent seizures and delivering the baby.
If you are less
than 34 weeks pregnant and a 24- to 48-hour delay is possible, you will likely
be given
antenatal corticosteroids to speed up the baby's lung
development before delivery.
Delivery
A vaginal
delivery is usually safest for the mother. It is tried first if she and the
baby are both stable.
If pre-eclampsia is rapidly getting worse or fetal
monitoring suggests that the baby cannot safely handle labour contractions, a
caesarean section (C-section) delivery is
needed.
After childbirth
If you have moderate to severe
pre-eclampsia, your risk of seizures (eclampsia) continues for the first 24 to
48 hours after childbirth. (In very rare cases, seizures are reported later in
the postpartum period.) So you may continue
magnesium sulfate for 24 hours after delivery.1
Unless you have chronic high blood pressure,
your blood pressure is likely to return to normal a few days after delivery. In
rare cases, it can take 6 weeks or more. Some women still have high blood
pressure 6 weeks after childbirth yet return to normal levels over the long
term.
If your blood pressure is still high after delivery, you may be given a blood pressure medicine. You will then have
regular checkups with your doctor.
Prevention
Lowering your
blood pressure helps to prevent pre-eclampsia. If you have chronic
high blood pressure, you can lower your
blood pressure before pregnancy by:
- Exercising.
- Eating a diet low in sodium and
rich in fruits and vegetables.
- Staying at a healthy weight.
When you are pregnant,
regular checkups are key to early detection and treatment. Prompt treatment is
vital to preventing the development of severe and possibly life-threatening
pre-eclampsia.
Home Treatment
Expectant management
If you develop
signs of
pre-eclampsia early in pregnancy, your doctor or
midwife may prescribe something called
expectant management at home, possibly for many weeks.
This may mean you are advised to stop working, reduce your activity level, or
possibly spend a lot of time resting (partial bedrest). Although partial bed
rest is considered reasonable treatment for pre-eclampsia, experts don't know how well it works to treat mild pre-eclampsia or high blood pressure.2 It is
known that strict bedrest may increase your risk of getting a blood clot in
the legs or lungs.
Whether you are required to reduce your
activity or have partial bedrest, expectant management limits your
ability to work, remain active, take care of children, and fulfill other
responsibilities. It may be helpful to follow some
tips for dealing with bedrest.
Daily monitoring
You may be required to monitor your own condition on a
daily basis. If so, you or another person (such as a trained family member or a
visiting nurse) will:
Keep a
written record of your results, including the dates and times you checked. Take
this record with you when you visit your doctor or midwife.
Social support
Worry and reduced
activity are difficult parts of having pre-eclampsia. It often helps
to talk with women who are or have been in the same situation.
Medications
Medicine for
pre-eclampsia may be used
to:
- Control high blood pressure.
Lowering high blood pressure doesn't prevent pre-eclampsia from getting worse. That's because high blood pressure is only a symptom of the condition, not a cause.
Your doctor may recommend blood pressure medicine if your blood pressure reaches high levels.
- Prevent seizures. Magnesium sulfate is usually started before delivery and
continued for 24 hours after delivery for women with pregnancy-related seizures
(eclampsia) and those who have moderate to severe
pre-eclampsia.
- Speed up fetal lung development. When possible, steroid medicine is given to the mother prior to a premature birth (up to 34
weeks of gestation). This medicine matures the baby's lungs over a 24-hour
period, which lowers the risk of breathing problems after birth.
Blood pressure medicines
Medicines used to control chronic high blood pressure during pregnancy include:
Some high blood pressure medicines are dangerous during pregnancy.3 If you take high blood pressure medicines, talk to your
doctor about the safety of your medicine. Discuss this before you become pregnant or as soon
as you learn you are pregnant. Make sure that your doctor has a complete list
of all medicines that you take.
Other blood pressure medicines that may be used include:
- Hydralazine. This is an
intravenous medicine for quickly lowering severely
high blood pressure during pregnancy.
- Labetalol. It's an
intravenous medicine for quickly lowering severely high blood pressure in the
hospital. It's also an oral medicine for controlling high blood pressure during
pregnancy.
Lowering blood pressure too
much or too fast can reduce blood flow to the placenta, causing problems for
the baby. So medicine is reserved for preventing severely high blood pressure
levels that may be life-threatening to you or your baby.
Surgery
There is no surgical treatment for
pre-eclampsia.
A caesarean section delivery is used when:
- A rapid delivery is medically needed for the
mother's or baby's well-being or survival.
- Induction of labour has
not been successful, usually after 24 hours.
- There are
medical reasons, such as
placenta previa, that make vaginal delivery
dangerous.
Other Places To Get Help
Organizations
| Society of Obstetricians and Gynaecologists of Canada
(SOGC) |
| 780 Echo Drive |
| Ottawa, ON K1S 5R7 |
| Phone: | 1-800-561-2416
(613) 730-4192 |
| Fax: | (613) 730-4314 |
| Email: | helpdesk@sogc.com |
| Web Address: | www.sogc.org |
| |
The mission of SOGC is to promote optimal women's
health through leadership, collaboration, education, research, and advocacy in
the practice of obstetrics and gynaecology. |
|
| Hypertension Canada |
| 3780 14th Avenue |
| Suite 211 |
| Markham, ON L3R 9Y5 |
| Phone: | (905) 943-9400 |
| Fax: | (905) 943-9401 |
| Web Address: | www.hypertension.ca/hypertension-home |
| |
Hypertension Canada: Understanding Hypertension provides educational information for people living with hypertension. |
|
References
Citations
- Roberts JM, Funai EF (2009). Pregnancy-related hypertension. In
RK Creasy, R Resnik, eds., Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice, 6th
ed., pp. 651–688. Philadelphia: Saunders.
- Sibai BM (2003). Diagnosis and management of gestational hypertension and preeclampsia. Obstetrics and Gynecology, 102(1): 191–192.
- Cooper WO, et al. (2006). Major congenital malformations after first-trimester exposure to ACE inhibitors. New England Journal of Medicine, 354(23): 2443–2451.
Other Works Consulted
- American College of Obstetricians and Gynecologists (2002, reaffirmed 2010). Diagnosis and management of preeclampsia and eclampsia. ACOG Practice Bulletin No. 33. Obstetrics and Gynecology, 99(1): 159–167.
- Campbell NRC, et al. (2011). Hypertension. In C Repchinsky, ed., Therapeutic Choices, 6th ed., pp. 450–477. Ottawa: Canadian Pharmacists Association.
- Society of Obstetricians and Gynaecologists of Canada (2008). Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy. Journal of Obstetrics and Gynaecology Canada, 30(3, Suppl 1). Also available online: http://www.sogc.org/guidelines/documents/gui206CPG0803_001.pdf.
Credits
| By | Healthwise Staff |
|---|
| Primary Medical Reviewer | Sarah Marshall, MD - Family Medicine |
|---|
| Specialist Medical Reviewer | William Gilbert, MD - Maternal and Fetal Medicine |
|---|
| Last Revised | December 28, 2012 |
|---|
