Hypertension in pregnancy

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UTG Medical Students’ Association

Hypertension is a chronic medical disorder characterized by persistent elevated blood pressure of greater the 140/90 mmHg. These readings are a measurement of the pressure exerted by blood on the surface of blood vessels. Imagine a pipe connected to a tap that is turned on wide open. The force of water coming out is considerably higher than when the tap is open just a little. Also, if any part of that pipe is weak it might easily burst open, if you’re also using that pipe to water a plant it might simply uproot it because of the pressure of the water. Taking this simple explanations in mind, it won’t be hard to imagine what this elevated pressure can do to systems in the human body.

On the other hand, lots of changes occur in pregnancy to accommodate the fetus. The fetus will need oxygen, food and nutrients so maternal blood volume will increase to account for this. The red blood cells will also increase but there will be a resultant decrease in the total peripheral resistance to help control this increased blood volume. Simply put, the pipe will expand more so the pressure won’t be too high to affect the fetus. This is what happens in a normal woman, when there are problems the picture changes altogether. A woman could have hypertension before she becomes pregnant or in the first half of her pregnancy, that is referred to as chronic hypertension. If she has hypertension after 20 weeks of getting pregnant then the hypertension is most likely caused by the pregnancy, this is clinically referred to as pregnancy induced hypertension (PIH). It is important to note that PIH complicates 5-17% of pregnancies in the sub region and it is one of the leading causes of maternal deaths in the Gambia. All known interventions have not been proven effective in reducing its occurrence.

There are different types of PIH based on the signs and symptoms that the woman presents with; they are gestational hypertension, preeclampsia, preeclampsia with superimposed hypertension and eclampsia. Gestational hypertension is just hypertension which develops in the second half of pregnancy. In preeclampsia, this hypertension is coupled with protein found in the urine, this is called proteinuria. Also coupled with this are problems of the kidney, liver, blood and even mental alterations in the mother. The fetus can also have problems with growth.

When preeclampsia becomes severe, there is more protein in the urine, more kidney and lung involvement and there might also be an associated HELLP syndrome (i.e Hemolysis, Elevated Liver enzymes and Low Platelet count). This is because of the extensive damage to the liver cause by this form on PIH. At the end of the spectrum lies Eclampsia, it is said to occur when all the previously mentioned symptoms are accompanied by seizures.

Some conditions that increase the risk of developing pre-eclampsia are Diabetes Mellitus, chronic hypertension, family history of hypertension, previous preeclampsia, multiple pregnancies like twins or triplets, the first pregnancy, a new partner, a very high age of the mother and black race. Like all risk factors, these do not definitely scream eclampsia but they definitely whisper loud enough to draw ones attention to it. Sadly, the cause of pre-eclampsia is not known but it happens when a series of placental events lead to widespread vascular lining disturbances.

The signs and symptoms of preeclampsia are vast due to the widespread organ involvement; they are pain in the right upper quadrant of the abdomen, visual disturbances, severe headache, hyperreflexia, hemolysis with renal involvement.

Eclampsia is a serious condition and can lead to a series of unfortunate events like premature birth of the fetus, death of the fetus in the uterus, poor fetal growth, acute kidney injury, pulmonary edema, separation of the placenta from the womb (abrubtio placentae), liver failure, coagulation disorders and it can even cause blindness in some cases.

When any of these are seen in a woman, it is important to rush to the nearest health facility so intervention can be made at the earliest possible time. When the mother is taken to the hospital, both her and her baby will be monitored, the hypertension will be controlled and decisions will be made on when and how he baby will be delivered. Usually the blood pressure is expected to return to normal within 6 weeks after the birth of the baby. If it doesn’t then the woman has chronic hypertension and should be managed medically by a physician or a cardiologist.

Low dose aspirin given before 16 weeks and continued till delivery of the baby has been shown to prevent the incidence of eclampsia but it is however important to confirm with your obstetrician before you start taking any pills. At least 1g per day of calcium is also another preventive method but Zinc, magnesium, fish oil and the other antioxidants have not been proven to be effective in the prevention of pregnancy induced hypertension.
The key to obtaining the best outcome for women with pregnancy induced hypertension and those at risk is early diagnosis, timely intervention and effective therapy. That being said, every woman should attend regular antenatal clinics once she finds out that she is pregnant so that routine test can be done. It is also very important to see a doctor even if you are planning to be pregnant because a lot of the causes of maternal and fetal deaths can be prevented by the interventions that can be done for you. Save a woman, save a country.Heath Corner Pic 2 1Heath Corner Pic 1 1