Hypertension in pregnancy: The basics

A normal pregnancy may be complicated with hypertension and it may bring some unmeasurable sufferings to the pregnant lady as well as for the family. So we should know a little information about this.

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Normally, during the earlier part of the pregnancy, the blood pressure starts to fall and keep falling up to 20 to 24 weeks of pregnancy. After this period, the blood pressure again starts to rise and reach to the pre-pregnancy state at the term. When this normal phenomenon is disturbed, we call it Hypertension in Pregnancy.

If any time, during pregnancy, we measure the blood pressure and find it more than 140/90 mmHg, we can call it Hypertension in Pregnancy. In another way, we have to keep the record of blood pressure in first booking (first visit a doctor after being pregnant) preferably in the first trimester (before the 14th week of gestation). In any subsequent visit, if systolic blood pressure increases more than 30 mmHg and diastolic blood pressure more than 15 mmHg from the blood pressure recorded on booking visit, we will call it Hypertension in Pregnancy.

For better classification, we should divide the whole pregnancy time (consider it a 40 weeks period) into two parts; first half (up to 20 weeks ) and second half.

Why am I calling the condition as "hypertension in pregnancy" rather than the term gestational hypertension or PIH(pregnancy induced hypertension)? It is because of the first type (or spectrum) of the hypertension in pregnancy. Let's see here:

Pre-existing hypertension: A lady may be a patient with hypertension and it continues during the whole pregnancy period. It is not actually pregnancy induced. And the blood pressure will be high in the first half of pregnancy unlike other types of hypertension in pregnancy. Approx 3-5% of pregnant ladies encounter this condition.

Pregnancy-induced hypertension(PIH) or gestational hypertension: In this condition, blood pressure will be above the normally expected limit (more than 140/90 mmHg) in the last half of pregnancy (after 20 weeks of gestation). In the first half of pregnancy, the blood pressure will be normal. There will be no associated proteinuria (passage of protein in the urine) or edema. Around 5-7% of the pregnant ladies suffer from this one.

Pre-Eclampsia: When the lady with PIH will develop proteinuria ( protein in the urine > 0.3g /24 hours) and/or edema the spectrum is known as Pre-Eclampsia. It occurs in 5% of the pregnancy.

Eclampsia: It is a severe form of pre-eclampsia where the lady develops a seizure or fits.