First of all, what types of high blood pressure cause problems in pregnancy? There are 3 main classes of blood pressure in pregnancy. These are noted as a systolic blood pressure greater than or equal to 140 or a diastolic blood pressure greater than or equal to 90. The first class is chronic hypertension. This occurs when elevated blood pressure is present before 20 weeks of pregnancy and is generally unrelated to pregnancy. This type of elevated blood pressure is usually before pregnancy. Just because you don’t check your BP outside of pregnancy doesn’t mean it’s not there :) The next two types are related to pregnancy: gestational hypertension, which develops after 20 weeks and does not cause spillage of protein in the urine, and preeclampsia, which also occurs after 20 weeks but is associated with proteinuria.
So, what happens if I have chronic hypertension during pregnancy? There can be actually be some lowering of chronic hypertension during the middle of pregnancy before an increase toward the end of pregnancy; however, the need for good control of your blood pressure is certainly important. Chronic hypertension places a mother at risk for fetal growth restriction (small baby), development of preeclampsia (just because you have chronic hypertension doesn’t get you off the hook for preeclampsia), placental abruption (early separation of the placenta prior to delivery causing bleeding and risk of fetal loss if not immediately managed), and also increased risk of cesarean section.
What about gestational hypertension or preeclampsia? These are managed similarly in their mild forms, and gestational hypertension may in fact be a mild form of preeclampsia. With development of gestational hypertension or mild preeclampsia, this condition must be monitored closely to ensure that severe preeclampsia doesn’t develop. In addition to the risks noted with chronic hypertension, women with preeclampsia are at risk for need for preterm delivery, maternal kidney or liver dysfunction, hemorrhage and even seizures. With severe preeclampsia, women may even be at risk for maternal death. After pregnancy, women with a history of preeclampsia have an increased risk for development of cardiovascular disease such as stroke, heart attack, elevated blood pressure and kidney dysfunction. They are also at risk for having preeclampsia again in a future pregnancy.
What happens to my baby if I have preeclampsia? Additional monitoring is required to monitor for development of severe preeclampsia. If you do develop severe preeclampsia, then your baby will likely have to be delivered early. Risks associated with preterm delivery may include respiratory distress, cerebral palsy, need for NICU stay, feeding issues or even loss of the baby in some cases; however, as bad as those risks sound, there may be a point in pregnancy where these risks are less than those associated with continuing the pregnancy.
How is elevated blood pressure treated in pregnancy? You may require medication to bring down your blood pressure, lab monitoring to check for development of severe preeclampsia, monitoring to check for fetal distress or even early delivery (with or without administration of steroids and/or magnesium prior to delivery). Magnesium may also be required to help prevent seizures associated with severe preeclampsia.
Are there risk factors for preeclampsia? First pregnancies, history of preeclampsia in other pregnancies, personal history of chronic hypertension or kidney disease, age 40 or older, carrying more than one baby, personal history of diabetes, clotting disorder or lupus, maternal obesity and pregnancy via in vitro fertilization.
Can I prevent preeclampsia? The best way to prevent preeclampsia is to ensure that you are as healthy as possible prior to beginning the pregnancy. If you are obese, weight loss may help reduce your risks. For chronic hypertension or diabetes, ensure that these are well-controlled prior to conceiving. If you have had a history of delivery prior to 34 weeks due to preeclampsia, your doctor may start you on a daily baby aspirin.
So, even though you might not feel miserable due to your high blood pressure, it is still very important to maintain good control in order to have the healthiest pregnancy outcome possible. If you have any of the risk factors listed above, be sure to talk to your provider about how to minimize your risks in your current (or future) pregnancies :)