Pregnancy and Hypertension


Hypertension is one of the most common medical complications during pregnancy. It can produce vital results for both mother and baby.


Hypertension Frequency in Pregnancy

It is seen in 7-10% of all pregnancies.


Pregnancy Hypertension Definition

According to The Committe of Terminology of ACOG, gestational hypertension is defined as ‘two blood pressure values of 140/90 mmHg and above obtained every 6 hours, or systolic (large blood pressure) 30mmHg and diastolic (small blood pressure) 15 mmHg or higher.

Blood pressure measurements should be made from the right arm while the pregnant woman is sitting and the arm is at the level of the heart. Blood pressure measurements should be made from the right arm while the pregnant woman is sitting and the arm is at the level of the heart.

High blood pressure is a finding that may be based on different causes and if it is detected in pregnant women, the risks will be different for the fetus and the mother according to the underlying cause. Therefore, the approach to pregnancy will be different.

When dealing with hypertension with the concept of pregnancy, we should examine in two separate groups:

1) ‘Pregnancy-induced hypertension’ caused by pregnancy, arising during pregnancy and returning with birth

2) ‘Chronic hypertension’ that exists before and without concomitant pregnancy, accompanying pregnancy.


Mechanism of Development of Gestational Hypertension

The development mechanism of gestational hypertension is the absence or insufficient formation of the ‘trophoblast cell’ (placental cell structure) invasion required for normal placental location as a result of disorders in the immune mechanisms between the mother and fetus. A number of factors result in local circulation in the uterus and placenta and endothelial (inner surface of the vessel) damage in the systemic circulation. Thus, the disease that originates from placenta actually turns into a systemic disease or brings along the result of widespread vasospasm (narrowing of the vessels) and not being able to adequately supply the different organs. In fact, as it is understood, hypertension is only a clinical finding of this syndrome, and when detected, the pathology has already settled in the organs in the female body and began to be affected. Gestational hypertension is a human disease.


Classification of Pregnancy and Hypertension

There are many suggestions for pregnancy and hypertension classification. Here I will write the widely used classification published by the Cerrahpasa group in our country’s Perinatology Journal:

1) Chronic hypertension:

Patients known before pregnancy and / or developing hypertensive retinopathy on ocular examination or whose postpartum hypertension continues

2) Pregnancy hypertension:

Cases occurring during pregnancy, without protein loss in the urine (less than 0.3 g / lt), hypertensive retinopathy do not develop in the eye examination, and the pressure is returned to normal after pregnancy.

3) Mild preeclampsia:

Cases with pregnancy hypertension and proteinuria (protein in urine above 0.3 g / lt) and diastolic blood pressure (small blood pressure) between 90-100 mm / hg.

4) Severe preeclampsia:

Diastolic blood pressure value measured over 6 hours in a pregnant woman at bed rest is above 100 mm / hg and / or protein loss over 5 g / lt in 24 hours urine, and / or decreased urine amount, and / or headache, vision loss, consciousness cases of central nervous system such as turbidity, pain in the stomach or right side, pulmonary oedema and bruising around the lips, and / or HELP syndrome (elevated blood breakdown products – hemolysis, elevated liver enzymes and decreased platelet level)

5) Chronic hypertension aggravated by pregnancy:

Cases accompanied by preeclampsia to chronic hypertension already existing before pregnancy

6) Eclampsia:

Cases in which convulsions (epileptic contraction), which we know are not related to any other reason, are added to the process.

Of the above mentioned cases, all groups except chronic hypertension were named as “pregnancy-induced hypertension”. Chronic hypertension can be detected before 20 weeks (except in special cases such as mole pregnancy), while pregnancy-related hypertension will not occur before 20 weeks.

The biggest benefit of this classification is to distinguish between light and heavy cases. Chronic hypertension, gestational hypertension and mild preeclampsia are also classified as ” mild group ”, severe preeclampsia, and chronic hypertension and eclampsia which are aggravated by pregnancy are also classified as “heavy group”. Approach to pregnancy should be arranged differently in these groups.

While seeking solutions to pregnancy and hypertension, while the treatment of existing hypertension is at the forefront in chronic hypertension, in pregnancy-induced hypertension; high blood pressure is an indicator of the underlying pathology.


Treatment in Pregnancy and Hypertension

When hypertension is identified in pregnant women, the most important point is to determine where it is in the above classification. While determining the follow-up and treatment path, two basic points are the determination of the woman’s condition and the well-being of the baby.

Protein should be monitored in the urine. A spot urine sample that is viewed randomly may not always produce accurate results. Therefore, if possible, protein should be checked in 24-hour urine. If there is no protein loss and blood pressure values are lower than 160/110, bed rest can be monitored on an outpatient basis by calling anti-hypertensive drugs and 2-3 times a week for control. If hypertension continues, if the cervix waist reaches a certain level of conformity at 36th week, artificial pain may be implanted and birth can be performed. If the blood pressure values progress to allow for waiting and if the fetus is well-received during NST follow-up and doppler evaluations; it may be possible to wait for the conformity of the cervix and the gestational week to reach weeks of 38-41. During follow-up, the possibility of developing pre-eclampsia should be taken into consideration in every control and the woman should be provided with daily blood pressure monitoring. The chance to wait is only possible by making sure that the mother and baby are in good condition and that preeclampsia does not develop. The delivery method can be performed in the form of normal birth or cesarean depending on the maturity of the cervix or the well-being of the baby.

If preeclampsia has developed, that is, protein output is detected in the urine, the approach to the pregnant woman changes.


Treatment in Preeclampsia 

The first thing to do in preeclampsia is the hospitalization of the mother and the rapid examination of the mother and baby. Hospital conditions should be able to meet intensive care for both mother and baby. Mainly, preeclampsia is a placental disease and its treatment means termination of pregnancy. In the decision to end the pregnancy, the gestational week or the urgency of the condition will be determined by making a distinction of mild or severe preeclampsia.

In the blood tests of the mother, clotting tests are performed with liver, kidney functions. The neurological examination examines whether the brain is affected. If there is pain in the upper and right side of the abdomen, the liver is checked by ultrasonography. Meanwhile, the fetus is evaluated with NST. Amniotic fluid amount, presence of retardation, biophysical profile and Doppler flow values are checked by Doppler ultrasonography.

At the end of these tests, mild or severe preeclampsia will be distinguished.

If it is mild preeclampsia, it can be waited until the 36th week as long as the picture remains stable and does not turn into severe preeclampsia. In the 36th week, depending on the suitability of the cervix and the well-being of the baby, it is delivered with artificial pain or birth, if necessary, by caesarean section.

If the condition is severe preeclampsia or if it has turned into a severe condition following mild preeclampsia, birth is performed as soon as possible regardless of gestational week. If:

* if blood pressure values are above 160/110

* if there are signs of liver damage

* if kidney failure is developing (protein loss in urine is above 5gr / lt, decreased urine output and impaired blood values)

* changes in consciousness, vision loss findings, development of eclampsia

* If platelet count is low and coagulation factors are impaired, widespread coagulation disorder has developed

* pulmonary edema such as bruising around the mouth, circulatory and respiratory system are affected

* If HELLP syndrome has developed

* If the fetus has growth retardation, doppler abnormalities, decreased amniotic fluid amount and NST abnormalities, it is severe preeclampsia and the woman should be delivered as soon as possible. It is the maternal life that should be kept in the foreground when severe preeclampsia develops. As the possibility of maternal loss is high, dynamical delivery should be planned. Vaginal birth or cesarean is planned by determining the chance of life according to the general condition of the mother and of course the pregnancy week of the fetus.

Convulsions were added to severe preeclampsia, and the neurological picture of eclampsia was further impaired. Treatment planning is the same as for severe preeclampsia.

Immediately after the diagnosis is made in severe preeclampsia and eclampsia, dosing from the vascular tract is planned and monitored very well, and magnesium sulphate treatment and antihypertensive treatment are started and treatment is continued until 24 hours after birth. The healing process will begin immediately after the placenta comes off. However, since the possibility of eclampsia continues for the first 24 hours, it is appropriate not to terminate the treatment immediately and to keep the patient under strict observation.


HELLP Syndrome

In addition to severe preeclampsia, Adult Respiratory Distress Syndrome (ARDS) may progress with Diffuse Intravascular Coagulation Disorder (DIC) and sepsis.

Haemolysis (red blood cell breakdown)

Elevated liver enzymes (elevation of liver enzymes)

Low platelet count (low platelet count)

Although HELLP syndrome, which brings serious life risks for the mother and fetus, develops most frequently after eclampsia, severe preeclampsia may also appear before symptoms become evident. When the diagnosis is made, delivery should be done directly. The hospital where the birth will take place should be able to meet the intensive care conditions for the mother and baby and it should be kept in mind that the need for blood and blood products may be high.