blood pressure is a measure of how hard your blood pushes against the walls of your arteries. if the force is too hard you have high blood pressure (also called hypertension ). when high blood pressure starts after 20 weeks of pregnancy it may be a sign of a very serious problem called preeclampsia. blood pressure is shown as two numbers. the top number ( systolic ) is the pressure when the heart pumps blood. the bottom number ( diastolic ) is the pressure when the heart relaxes and fills with blood. blood pressure is high if the top number is more than 140 millimeters of mercury (mm hg) or if the bottom number is more than 90 mm hg. for example blood pressure of 150/85 (say "150 over 85") or 140/95 is high. or both numbers can be high such as 150/95. a woman may have high blood pressure before she gets pregnant. or her blood pressure may start to go up during pregnancy. if you have high blood pressure during pregnancy you need to have checkups more often than women who do not have this problem. there is no way to know if you will get preeclampsia. this is one of the reasons that you are watched closely during your pregnancy. high blood pressure and preeclampsia are related but they have some differences. webmd medical reference from healthwise this information is not intended to replace the advice of a doctor. healthwise disclaims any liability for the decisions you make based on this information. © 1995-2011 healthwise incorporated. healthwise healthwise for every health decision and the healthwise logo are trademarks of healthwise incorporated.
what are high blood pressure and preeclampsia?