Blood pressure is simply the pressure exerted by blood on walls of arteries. Blood pressure has two components – systolic pressure (top number) and diastolic pressure (bottom number). When the systolic pressure is over 140 mm of Hg or the diastolic pressure is over 90 mm of Hg, it is considered that the person has blood pressure.
High blood pressure (also called hypertension) during pregnancy may pose problems for both mother and fetus. So it is important that you get your blood pressure checked regularly during pregnancy.
Types Of Hypertension During Pregnancy
If you develop hypertension before pregnancy, before 20 wk of pregnancy or it lasts even after 12 wk after delivery, it is called chronic hypertension. If you develop hypertension after 20 wk of pregnancy, it is called gestational hypertension. Such hypertension usually resolves after delivery. If in addition to hypertension, you are passing excess protein in urine, after 20 wk of pregnancy, it is called preeclampsia, which can sometimes be fatal. Gestational hypertension can sometimes lead to preeclampsia.
Risk Factors And Causes Of Hypertension During Pregnancy
There are several factors that increase the chances of your developing hypertension during pregnancy. They are family history of hypertension during pregnancy, age over 35 years, adolescent pregnancy, renal disease, diabetes, obesity, rheumatoid arthritis, multiple gestation (that is, twins, triplets etc.) and placental abnormalities. Exact cause of hypertension during pregnancy is not known.
Symptoms Of Hypertension During Pregnancy
Usually there are no symptoms. But if the blood pressure is very high, you can have headaches, shortness of breath and blurred vision. Preeclampsia can cause sudden weight gain and swelling of face and hands due to fluid accumulation. Decreased urination and abdominal pain may also be present.
Complications Of Hypertension During Pregnancy
The placenta gets less blood flow, so the developing baby gets not only less oxygen but also less nutrients. This can slow down the growth of the baby and lead to low birth weight.
Placenta may separate from uterus prematurely, leading to heavy bleeding and also drastic drop in supply of oxygen to the baby. Sometimes you may need to have premature delivery to pre-empt life-threatening complications. Even if the blood pressure is normalized after pregnancy, you are at increased risk of hypertension during subsequent pregnancies and also cardiovascular disease in the future.
Management Of Hypertension During Pregnancy
If you already have hypertension, then before becoming pregnant make sure that you keep the blood pressure in check. You can do this by taking your medications regularly, cutting down the salt intake, being physically active and, if possible, doing exercise, and losing excess weight. Avoid smoking and alcohol intake.
Once you are pregnant, it is important that you undergo regular check-ups so that hypertension can be detected early. If you do develop hypertension, you need to take antihypertensives. Some antihypertensives are harmful for the fetus. Methyldopa, labetalol and hydralazine are the preferred antihypertensives in pregnancy. Do not change the dose or stop the medication on your own without consultation with your doctor.
Preeclampsia needs to be monitored closely. Aspirin in low doses and calcium supplements are thought to prevent preeclampsia. Steroids like dexamethasone and betamethasone may be needed to help the lungs of the fetus mature faster. Early delivery by cesarean section may be indicated if there are dangerous complications.