When the heart pumps blood through the body, the measure of the pressure against the vessels’ walls is called blood pressure. High blood pressure while pregnant (also known as Hypertension in Pregnancy), carries serious health risks. Severe hypertension can threaten you and you’re baby’s health. Some women have high blood pressure before they get pregnant. Others have high blood pressure for the first time during pregnancy.
Hypertension during pregnancy can lead to a very dangerous complication called preeclampsia. Severe forms of preeclampsia may develop alongside even more dangerous conditions, such as eclampsia (seizures during preeclampsia) and HELLP syndrome.
All pregnant women need to understand the warning signs of these conditions, which can be fatal if left untreated. Hypertensive disorders of pregnancy are common and remain a significant cause of maternal and fetal morbidity.
Chronic Hypertension in Pregnancy
Chronic hypertension in pregnancy is a condition that affects the patient throughout his or her life. Because most cases of high blood pressure have no outward symptoms, it can be hard to tell whether the condition is chronic. This is high blood pressure that you have before you get pregnant or that develops before 20 weeks of pregnancy. It doesn’t go away once you give birth. About 1 in 4 women with chronic hypertension has preeclampsia during pregnancy. If you’re at high risk for preeclampsia, your provider may treat you with low-dose aspirin to prevent it.
Typically, a doctor will consider your hypertension chronic if:
- You have high blood pressure during the first 20 weeks’ gestation.
- You were diagnosed with high blood pressure prior to your pregnancy.
American College of Obstetrics and Gynecology (ACOG) defines chronic hypertension as systolic BP ≥ 140 mm Hg or diastolic BP ≥ 90 mm Hg on 2 occasions before 20 weeks of gestation. If you have chronic hypertension, you need to keep an eye on your blood pressure throughout your pregnancy. You may need to get a special device so you can self-monitor at home.
If you had a hypertensive disorder in a prior pregnancy, your doctor might recommend a daily low-dose aspirin beginning late in your first trimester.
Some women who had normal blood pressure prior to pregnancy may develop hypertension in the latter half of pregnancy. This is called gestational hypertension, also known as pregnancy-induced hypertension, and it poses some risks for the mother and baby.
Gestational hypertension usually subsides after the baby is born, but in some cases, the mother still has an increased risk of high blood pressure for the rest of her life.
Chronic hypertension with superimposed preeclampsia occurs in women with chronic hypertension before pregnancy who develop worsening high blood pressure and protein in the urine or other blood pressure-related complications during pregnancy.
Complications of Hypertension in Pregnancy
Both types of hypertension during pregnancy strain your kidneys, heart, and other systems. They can also cause problems for your growing baby.
- Decreased blood flow to the placenta. If the placenta doesn’t get enough blood, your baby might receive less oxygen and fewer nutrients. This can lead to slow fetal growth (intrauterine growth restriction), low birth weight or premature birth or small baby for gestational age.
- Prematurity can lead to breathing problems, increased risk of infection and other complications for the baby.
- Placental abruption. Preeclampsia increases your risk of this condition in which the placenta separates from the inner wall of your uterus before delivery. Severe abruption can cause heavy bleeding, which can be life-threatening for you and your baby.
- Intrauterine growth restriction. Hypertension might result in slowed or decreased fetal growth restriction (intrauterine growth restriction).
- Organ damage. Poorly controlled hypertension can result in injury to your brain, heart, lungs, kidneys, liver and other major organs. In severe cases, it can be life-threatening.
- Premature delivery. Sometimes an early delivery is needed to prevent potentially life-threatening complications when you have high blood pressure during pregnancy.
- Future cardiovascular disease. Having preeclampsia might increase your risk of future heart disease and blood vessel (cardiovascular) disease. Your risk of future cardiovascular disease is higher if you’ve had preeclampsia more than once or you’ve had a premature birth due to having high blood pressure during pregnancy.
- Cesarean birth. If conditions are worsening, and the health care doctor believes it would be unsafe to deliver naturally, a C-section will be recommended.
- Preeclampsia. Women with hypertension have an increased chance of developing preeclampsia.
Hypertension and Preeclampsia
Preeclampsia is a hypertensive disorder that affects roughly 5-8% of pregnancies in the U.S. Researchers are still studying the exact causes for preeclampsia, but it appears that the problem begins in the placenta.
When you become pregnant, the placenta is the organ that develops to feed and send oxygen to the fetus to help it grow. New blood vessels must form in order to send nutrient-rich blood into the placenta.
But in women with preeclampsia, the new blood vessels are more narrow than usual and don’t seem to react as well to the mother’s hormones. They’re unable to carry enough blood, which slows the baby’s development, causes hypertension, and damages other organ systems in the mother — especially the kidneys.
Preeclampsia can be fatal to the mother and baby if left untreated. Delivering the baby can often cure preeclampsia. When making a decision about treatment, your health care provider takes into account several factors. A pre-term delivery carries its own serious risks for the infant. In severe cases, this can pose a difficult decision for the mother, her family, and her doctor.
The risks include how severe it is, how many weeks pregnant you are, and what the potential risks to you and your baby are:
- If you are more than 37 weeks pregnant, your health care provider will likely want to deliver the baby.
- If you are less than 37 weeks pregnant, your health care provider will closely monitor you and your baby. This includes blood and urine tests for you.
Monitoring for the baby often involves ultrasound, heart rate monitoring, and checking on the baby’s growth. You may need to take medicines, to control your blood pressure and to prevent seizures. Some women also get steroid injections, to help the baby’s lungs mature faster. If the preeclampsia is severe, your provider may want you to deliver the baby early.
The symptoms usually go away within 6 weeks of delivery. In rare cases, symptoms may not go away, or they may not start until after delivery (postpartum preeclampsia). This can be very serious, and it needs to be treated right away.
Risk Factors for Preeclampsia
Preeclampsia appears to affect some types of pregnancies more than others. Here are some conditions that come with an increased risk for preeclampsia. These include:
- First pregnancy
- Over 40 years of age
- Family history of preeclampsia. Preeclampsia may have a genetic component.
- New father. Each pregnancy from a new partner increases the risk of preeclampsia.
- Multiple gestations. Women carrying twins, triplets, or more, are more susceptible to preeclampsia.
- Period of time between pregnancies. If your last pregnancy was either less than two years ago, or more than 10 years ago, your current pregnancy carries a higher risk of preeclampsia.
- Medical conditions. Women with a history of chronic hypertension, migraines, diabetes (type 1 or type 2), blood clots, kidney disease, or lupus have a higher chance of developing preeclampsia.
Symptoms of Preeclampsia
Preeclampsia usually manifests after the first 20 weeks of pregnancy. A spike in blood pressure can be the first sign of preeclampsia, which is why monitoring your blood pressure during pregnancy is so important. Other symptoms include:
- Severe headaches
- Sensitivity to light, blurred vision, or temporary loss of vision
- Proteinurea (excessive protein in the urine)
- Decrease in urination
- Pain in the upper abdomen, especially on the right side
- Difficulty breathing, due to fluid in the lungs
- Sudden weight gain or edema (swelling) in the hands and face – these signs are considered less reliable, since both are also normal symptoms of pregnancy
Diligently attend all of your prenatal care appointments, and keep a log of any symptoms that you notice. Your health care provider will check your blood pressure and urine at each prenatal visit. If your blood pressure reading is high (140/90 or higher), especially after the 20th week of pregnancy, your provider will likely want to run some more tests. If you’re experiencing severe abdominal pain, severe headaches, vision problems, and shortness of breath, you must contact your doctor immediately or go to the emergency room.
Nausea, vomiting, swelling, and other aches and pains are fairly common during pregnancy, and may not necessarily be cause for concern. However, if you’re worried about your symptoms, please don’t hesitate to contact us with questions.
Eclampsia is another life-threatening condition associated with preeclampsia. Eclampsia is the onset of seizures in a woman with severe preeclampsia. It may cause muscle aches and pains, severe agitation, and a loss of consciousness.
About 2% of women with eclampsia die from complications. Because the condition is so dangerous, women with severe preeclampsia are often given anti-seizure medications. Many doctors give magnesium sulfate or other antihypertensive medications to their patients during labor and for a few days afterward to help prevent eclampsia.
How is Preeclampsia Treated?
If you have a mild case of either gestational hypertension or preeclampsia, you can manage your health on an outpatient basis, by keeping track of your blood pressure at home and performing a daily kick count to monitor your baby’s movement. You’ll need to see your doctor once or twice a week. Depending on your baby’s development and your health, your OB-GYN may recommend delivery at 37 weeks or earlier.
Severe preeclampsia must be treated in the hospital. Women who are 34 weeks pregnant should deliver the baby as soon as medically feasible. Any earlier than that, and the decision to deliver early might be a difficult one that you and your doctor need to make together.
The doctor may be able to give the baby corticosteroids in utero to help the lungs to develop more quickly and prepare for life outside the womb. You will likely need blood pressure and anti-seizure medication to stay as healthy as possible. If either you or your baby’s condition gets worse, you may need to deliver the baby right away.
HELLP syndrome is a variation of preeclampsia, and a life-threatening pregnancy complication. It is rare – only an estimated 15% of women with preeclampsia will develop HELLP syndrome.
Like preeclampsia, HELLP typically occurs in the later stages of pregnancy, or even after the baby is born.
HELLP stands for:
- Hemolysis – the breaking down of red blood cells
- Elevated Liver enzymes – indicates damage to the liver
- Low Platelet count – blood may be unable to clot properly, also called thrombocytopenia
Symptoms of HELLP
The symptoms for HELLP are similar to preeclampsia. Expectant mothers need to be aware of the symptoms of HELLP, as the condition can be fatal in up to 25% of cases worldwide.
- High blood pressure
- Proteins in the urine
- Changes in vision (temporary loss of vision, blurry vision)
- Indigestion or pain after a meal
- Pain in the abdomen, particularly in the upper right side
If Hypertension in Pregnancy is left untreated, severe complications can occur. Fortunately, these can usually be prevented if the symptoms are identified early, and emergency medical attention is sought. If you’re experiencing these symptoms, please call your doctor or 911 immediately.
If you or your family has a history of hypertension, it’s critically important for you to fully understand the risks and symptoms associated with hypertension in pregnancy. These issues can be scary to talk about, but it’s never too early to discuss your concerns with your doctor. Be sure to ask your doctor any questions you may have at your regular prenatal visits.
Schedule a preconception checkup. This is a medical checkup you get before pregnancy to take care of health conditions that may affect your pregnancy, such as hypertension during pregnancy.