Preeclampsia is defined as high blood pressure and excess protein in the urine after 20 weeks of pregnancy in a woman who previously had normal blood pressure. Even a slight increase in blood pressure may be a sign of preeclampsia. Left untreated, preeclampsia can lead to serious — even fatal — complications for both you and your baby.
If you have preeclampsia, the only cure is delivery of your baby. If you're diagnosed with preeclampsia too early in your pregnancy for delivery to be an option, you and your doctor face a challenging task. Your baby needs more time to mature, but you need to avoid putting yourself or your baby at risk of serious complications.
Preeclampsia can develop gradually but often starts abruptly, after 20 weeks of pregnancy. Preeclampsia may range from mild to severe. If your blood pressure was normal before your pregnancy, signs and symptoms of preeclampsia may include:
Swelling (edema), particularly in your face and hands, often accompanies preeclampsia. Swelling isn't considered a reliable sign of preeclampsia, however, because it also occurs in many normal pregnancies.
When to see a doctor
Because headaches, nausea, and aches and pains are common pregnancy complaints, it's difficult to know when new symptoms are simply part of being pregnant and when they may indicate a serious problem — especially if it's your first pregnancy. If you're concerned about your symptoms, contact your doctor.
Preeclampsia used to be called toxemia because it was thought to be caused by a toxin in a pregnant woman's bloodstream. This theory has been discarded, but researchers have yet to determine what causes preeclampsia. Possible causes may include:
Other high blood pressure disorders during pregnancy
Preeclampsia develops only during pregnancy. Risk factors include:
Other possible factors
Most women with preeclampsia deliver healthy babies. The more severe your preeclampsia and the earlier it occurs in your pregnancy, however, the greater the risks for you and your baby. Preeclampsia may require induced labor and delivery. Cesarean birth isn't always needed in these cases. But your doctor might recommend cesarean delivery if inducing labor becomes difficult due to the gestational age of your baby. The earlier the gestational age, the more difficult inducing labor might be.
Complications of preeclampsia may include:
Preparing for your appointment
It's a good idea to be well prepared for your appointment with your obstetrician. Here's some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
Preparing a list of questions ahead of time will help you make the most of your time with your doctor. List your questions from most important to least important. For preeclampsia, some basic questions to ask your doctor include:
In addition to the questions that you've prepared, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
Tests and diagnosis
Preeclampsia usually shows up during a routine prenatal blood pressure check followed by a urine test. The diagnosis depends on the presence of high blood pressure and protein in your urine after 20 weeks of pregnancy. Substances called biochemical markers in your blood and urine may be warning signs of preeclampsia. That's one of the reasons it's essential to seek early and regular prenatal care throughout your pregnancy.
A blood pressure reading in excess of 140/90 mm Hg is abnormal in pregnancy. However, a single high blood pressure reading doesn't mean you have preeclampsia. If you have one reading in the abnormal range — or a reading that's substantially higher than your usual blood pressure — your doctor will closely observe your numbers. Having a second abnormal blood pressure reading six hours after the first may confirm your doctor's suspicion of preeclampsia. You may also need additional blood pressure readings and urinary protein measurements.
Treatments and drugs
The only cure for preeclampsia is delivery. You're at increased risk of seizures, placental abruption, stroke and possibly severe bleeding until your blood pressure decreases. Of course, if it's too early in your pregnancy, delivery may not be the best thing for your baby.
If you've had preeclampsia in one or more previous pregnancies, some experts recommend more frequent prenatal visits than normally recommended for pregnancy. Your doctor may ask you to come in every two weeks between the 20th and 32nd week of your gestation, and weekly after that until delivery.
If you have more severe preeclampsia, you may need bed rest in the hospital. In the hospital, you may have regular nonstress tests or biophysical profiles to monitor your baby's well-being and measure the volume of amniotic fluid. A lack of amniotic fluid is a sign of poor blood supply to the baby.
In more severe cases, it may not be possible to consider your baby's gestational age or the readiness of your cervix. If it's not possible to wait, your doctor may induce labor or schedule a C-section earlier in your pregnancy. During delivery, you may be given magnesium sulfate intravenously to increase uterine blood flow and prevent seizures.
After delivery, expect your blood pressure to return to normal within a few weeks.
Coping and support
Discovering that you have a potentially serious pregnancy complication can be frightening. If you're diagnosed with preeclampsia late in your pregnancy, you may be surprised and scared to know that you'll be induced right away. If you're diagnosed earlier in your pregnancy, you may spend many hours of bed rest worrying about your baby's health.
It may help to learn as much as you can about your condition. In addition to talking to your doctor, do some research. On the other hand, if reading about preeclampsia and its possible complications only makes you more nervous and worried, find a distraction. Make sure you understand when to call your doctor, and then find something else to occupy your time.
Coping with bed rest
To make bed rest tolerable, consider these tips:
Make the best of the situation by focusing on the fact that you're doing what's best for you and your baby.
There's no known way to prevent preeclampsia. Eating less salt or changing your activities during pregnancy doesn't reduce the risk. The best way to take care of yourself — and your baby — is to seek early and regular prenatal care. If preeclampsia is detected early, you and your doctor can work together to prevent complications.
There's some evidence that taking certain vitamins, such as vitamin D, may lower the risk of preeclampsia. Ask your doctor what he or she recommends. Don't take anything during pregnancy without your doctor's approval.
Last Updated: 2011-04-21
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