Be sure to scroll to the bottom to watch a live discussion I did on preeclampsia!
What is preeclampsia?
Blood pressure disorders are the most common medical complication experienced during pregnancy, occurring in approximately 5-10% pregnancies. The most common blood pressure disorder, preeclampsia, is unique to pregnancy, and although the primary finding is high blood pressure, it can also be associated with other signs of damage to various organ systems. Damage to the kidneys is most commonly seen, and usually results in excess amounts of protein in the urine. As the disease process progresses, however, compromise to the liver, brain, and vascular system can also occur. This damage to the organs occurs because preeclampsia causes blood vessels to constrict and spasm, which not only leads to elevated blood pressure, but also decreased blood flow to these vital organs.
Signs and symptoms of preeclampsia
Your obstetrician will check for signs of preeclampsia at each prenatal visit by checking blood pressure and assessing the urine for protein; these assessments increase with more frequent prenatal visits towards the end of pregnancy. Your obstetrician will also screen for symptoms of preeclampsia such as the following:
- Headache that doesn’t go away with over-the-counter medications
- Visual changes
- Mid-abdominal or right upper abdominal pain
- Any new-onset nausea and vomiting (typically after 20 weeks)
- Swelling in the face, hands, or extremities
Some of the symptoms of preeclampsia can resemble “normal” symptoms of pregnancy. In addition, some women will not experience any of the symptoms and, therefore, be quite surprised when they find out they have preeclampsia. If you are not sure if what you are experiencing is normal, it is best to ask your obstetrical care provider. It is also important to keep your prenatal appointments so you can be routinely screened.
Not only can signs and symptoms of preeclampsia occur in the pregnant person, but certain signs may also present with the developing fetus. In some cases, the fetus may not be growing well in the uterus or the amniotic fluid volume may be low. If any of these issues arise during the pregnancy, both patient and fetus will be very carefully monitored.
Causes of and risk factors for preeclampsia
The exact cause of preeclampsia is unknown. Many theories have been suggested and explored, but no definitive answer has ever been reached. We do know that certain women have a higher risk of developing preeclampsia than the general pregnant population. Risk factors for preeclampsia include: first pregnancy, obesity, gestational diabetes, multi-fetal gestation (i.e. twins, triplets, etc.), family history of preeclampsia or preeclampsia in a prior pregnancy or poor outcome in a previous pregnancy such as placental abruption or fetal death. Extremes of age are also an important risk factor; persons <20 and >35 have a higher risk of developing the preeclampsia. Finally, persons with certain pre-existing medical or genetic conditions are at higher risk. This includes those with chronic hypertension, kidney disease, Type 1 diabetes, or blood clotting disorders.
Another potential risk factor has come into play in the recent years with advances in assisted reproductive technology (ART), such as the increased use of intrauterine insemination (IUI) and in vitro fertilization (IVF). Persons aged 35 years and older have a higher risk of encountering difficulties conceiving and are more frequently turning to ART to achieve pregnancy. These techniques can challenge the immune system of the patient, which may put them at a higher risk for developing preeclampsia. In addition, many persons undergoing ART also become pregnant with twins or triplets. The combination of ART and multi-fetal gestation further increases the likelihood of developing preeclampsia.
Can preeclampsia be prevented?
If you have certain risk factors for preeclampsia, your doctor will recommend that you take low-dose aspirin starting at 12-16 weeks and continuing until you deliver. The low-dose aspirin used to prevent or delay the onset of preeclampsia. Always follow your physician’s instructions before taking this medication. It is also a good idea to take your blood pressures at home using a home blood pressure monitor. The blood pressure monitor is great if you need to keep a close watch on your blood pressure–be sure to right down all blood pressure measurements in case your doctor wants to review them. This table from the US Prevention Services Task Force illustrates how low-dose aspirin would be administered to someone who might be at risk of developing preeclampsia.
Some contributing factors to high blood pressure can be controlled and some can’t. Follow your doctor’s instructions about diet and exercise, as well as these follow these tips:
- Use little or no added salt in your meals.
- Drink 6-8 glasses of water a day.
- Don’t eat a lot of fried foods and junk food.
- Get enough rest.
- Exercise regularly.
- Elevate your feet several times during the day.
- Avoid drinking alcohol.
- Avoid beverages containing caffeine.
- Your doctor may suggest you take the prescribed medicine.
When does preeclampsia occur?
Preeclampsia is usually diagnosed after 20 weeks of gestation, but most often will develop after 37 weeks of gestation. If it occurs before 34 weeks of pregnancy it is considered “early onset preeclampsia. It can even occur during the postpartum period! It is extremely important that you tell you doctor if you even had preeclampsia or elevated blood pressures in the past.
Diagnosis of preeclampsia
It is typically diagnosed by obtaining elevated blood pressure readings of >140/90, at least two times and measured 6 hours apart. Once these blood pressures are reached, other tests will be performed to assist in the diagnosis. Laboratory tests will be done to look at how the liver, kidneys, and vascular system are functioning. If protein is found in the urine or the laboratory values show signs of organ compromise, the diagnosis is confirmed. In addition, if any of the symptoms of preeclampsia such as persistent headache, visual changes, or significant abdominal pain are present, the diagnosis of preeclampsia is also likely and you will be very closely monitored. It is important that the diagnosis of preeclampsia be achieved in a timely fashion, in order to prevent the development of more serious complications such seizures, placental abruption, or bleeding in the brain.
Treatment of preeclampsia
The definitive treatment for preeclampsia is delivery of the fetus. Luckily, most cases of preeclampsia are diagnosed near the end of pregnancy, which decreases the risks of complications associated with premature delivery. If preeclampsia develops before 37 weeks of gestation, which is considered preterm, hospitalization and close monitoring for worsening signs or symptoms is usually indicated. Many patients who are diagnosed with preeclampsia before 37 weeks and are stable will be monitored until they reach 37 weeks of gestation, at which time delivery will be recommended. Although preeclampsia is more commonly diagnosed late in the third trimester, it is important to keep in mind that it can develop much earlier in pregnancy. As a result, it is important to let your obstetrician know of any signs or symptoms you may be experiencing. If you are diagnosed with preeclampsia early in pregnancy, your doctor will weigh the risks and benefits of keeping you pregnant as long as possible versus delivery of the fetus. Finally, preeclampsia can sometimes develop into more severe forms of the disease, i.e. HELLP syndrome and eclampsia. If either of these develops, delivery, regardless of gestational age, is recommended.
Top resources for more info on preeclampsia:
- The Babies After 35 blog on preeclampsia
- Preeclampsia.org
- Preeclampsia Registry
- NICHD
If you have any particular concerns about preeclampsia and your pregnancy, be sure to talk to your doctor. This condition should never be overlooked or taken lightly. Be sure to share this information if you think it might help someone!
Watch my discussion with Dr. Clark of Babies After 35 for more info!
Pro-tip!
The good news for pregnant persons is that having a healthy, normal pregnancy is much more likely than developing preeclampsia. With that said, being informed about the disease, knowing your risk factors, and being in-tune to your body is very important. If you have any concerns about symptoms you are having and think they may be related to preeclampsia, do not hesitate to see your obstetrician.
Listen to the podcast!
Reference:
Gabbe, S.G., Simpson, J.L., and Niebyl, J.R. (2007) Obstetrics: Normal and Problem Pregnancies, 5th Edition. Philadelphia, PA: Elsevier Health Sciences, 863-866.