Blood pressure is the force of blood that pushes against the walls of your arteries. Arteries are blood vessels that carry blood away from your heart to other parts of the body. If the pressure in your arteries becomes too high, you have high blood pressure (also called hypertension). High blood pressure can put extra stress on your heart and kidneys. This can lead to heart, disease, kidney disease and stroke.
Some women have high blood pressure before they get pregnant. Others have high blood pressure for the first time during pregnancy. If you have high blood pressure, talk to your health care provider. Managing your blood pressure can help you have a healthy pregnancy and a healthy baby.
Your blood pressure reading is given as two numbers: the top (first) number is the pressure when your heart contracts (gets tight) and the bottom (second) number is the pressure when your heart relaxes. A normal blood pressure is 119/79 or lower. High blood pressure happens when the top number is 140 or greater, or when the bottom number is 90 or greater. Your blood pressure can go up or down during the day.
At each prenatal care checkup, your health care provider checks your blood pressure. To do this, he or she wraps a cuff (band) around your upper arm, then pumps air into the cuff to measure the pressure in your arteries when the heart contracts and then relaxes. If you have a high reading, your health care provider can recheck it to find out for sure whether you have high blood pressure.
High blood pressure can cause problems for you and your baby during pregnancy, including:
Preeclampsia
Preeclampsia occurs when a pregnant woman has high blood pressure, and this is a signal that some of her organs, like her kidneys and liver, may not be working properly. Signs and symptoms of preeclampsia include having protein in the urine, changes in vision, and severe headaches. Preeclampsia can be a serious medical condition. Even if you have mild preeclampsia, you need treatment to make sure it does not get worse. Without treatment, preeclampsia can cause kidney, liver and brain damage. In rare cases, it can lead to life-threatening conditions like eclampsia and HELLP Syndrome. Eclampsia causes seizures and can lead to coma. HELLP syndrome is when you have serious blood and liver problems.
Premature Birth
This is birth that happens too early, before 37 weeks of pregnancy. Even with treatment, a pregnant woman with severe high blood pressure or preeclampsia may need to give birth early to avoid serious health problems for her and her baby.
Low Birth Weight
This is when a baby is born weighing less than 5 pounds, 8 ounces. High blood pressure can narrow blood vessels in the uterus. Your baby may not get enough oxygen and nutrients, causing him or her to grow slowly.
Placental Abruption
The placenta grows in the uterus and supplies the baby with food and oxygen through the umbilical cord. A placental abruption is a serious condition in which the placenta separates from the wall of the uterus before birth. If this happens, your baby may not get enough oxygen and nutrients in the womb. You also may have serious bleeding from the vagina.
There are two types of high blood pressure that can occur during pregnancy:
Chronic Hypertension
This is high blood pressure that you have before you get pregnant or that develops before 20 weeks of pregnancy. It does not go away once you give birth. If you are at high risk for preeclampsia, your health care provider may treat you with low-dose aspirin to prevent it.
If you have chronic hypertension, your health care provider will check your blood pressure and urine at each prenatal care visit. You may need to check your blood pressure at home, too. Your health care provider may use ultrasound and fetal heart rate testing to check your baby’s growth and overall health. Your health care provider also checks for signs of preeclampsia.
If you were taking medicine for chronic hypertension before pregnancy, your health care provider will make sure it is safe to take during pregnancy. If it is not, he or she will switch you to a safer medicine. Some blood pressure medicines can harm your baby during pregnancy.
During the first half of pregnancy, your blood pressure often falls. If you have mild hypertension and took medicine for it before pregnancy, your health care provider may lower the dose of medicine you take. Or you may be able to stop taking medicine during pregnancy. Do not stop taking any medicine before you talk to your health care provider. Even if you did not take blood pressure medicine in the past, you may need to start taking it during pregnancy.
Gestational hypertension
This is a type of high blood pressure that only pregnant women can get. It starts after 20 weeks of pregnancy and goes away after you give birth. This condition usually causes a small rise in blood pressure, but some women develop severe hypertension and may be at risk for more serious complications later in pregnancy, like preeclampsia.
During pregnancy, your health care provider checks your blood pressure and urine at every prenatal visit. He or she may use an ultrasound and fetal heart rate testing to check your baby’s growth and health.
There is no known way to prevent gestational hypertension. But if you are overweight, getting to a healthy weight before pregnancy may lower your chances of having this condition. Even though gestational hypertension usually goes away after birth, you may be more likely to develop hypertension later in life. Healthy eating, staying active and getting to a healthy weight after pregnancy can help prevent high blood pressure in the future.
Here is a list of great ways to manage high blood pressure during pregnancy:
- Go to all your prenatal care checkups, even if you’re feeling fine.
- If you need medicine to control your blood pressure, take it every day. Your provider can help you choose one that’s safe for you and your baby.
- Eat health foods. Don’t eat foods that are high in salt, like soup and canned foods. They can raise your blood pressure.
- Stay active! Being active for 30 minutes each day can help you manage your weight, reduce stress and prevent problems like preeclampsia.
- Don’t smoke or drink alcohol, use drugs, or abuse prescription drugs.
Having high blood pressure during pregnancy may be scary and concerning at first, but if handled correctly and if you follow your health care providers instructions, you and your baby can remain healthy throughout the pregnancy and beyond.