You will notice that your blood pressure is checked at every ante natal appointment during pregnancy.
Blood pressure is not usually raised during the first 20 weeks of pregnancy and may be lower than usual.
If you get a high blood pressure reading it may be because your blood pressure was already high before you became pregnant. If it is only mildly raised you will probably be advised to make lifestyle changes, with medication only being prescribed for more serious cases.
If your blood pressure is very high you may need to be admitted for tests in hospital to check if you have a problem such as diabetes or a kidney disorder and your baby will be monitored to ensure that he or she is growing properly.
After 20 weeks of pregnancy, blood pressure normally drops as the blood vessels dilate due to the action of hormones released in pregnancy and the placenta pumps blood to the baby. Sometimes low blood pressure in pregnancy can cause fainting and dizziness.
In later pregnancy (after 28 weeks) high blood pressure can be a sign of pre-eclampsia – which 1 in 4 women experience with a first baby (it is less common in later pregnancies).
If left untreated, eclampsia can develop and this is dangerous to the lives of both mother and child. Other symptoms of pre-eclampsia are swelling in the ankles, hands or feet,sudden weight gain and protein in the urine. If you have this you will be admitted to hospital for monitoring and may need to give birth early if blood pressure continues to rise or your baby’s growth is affected.
Usually high blood pressure due to eclampsia comes back down after the birth of the child and no further treatment is necessary although you may be more likely to suffer high blood pressure later in life and should ask to be checked regularly.