Risk factors for the development of high blood pressure in pregnancy | Gestational hypertension – Is it dangerous?

Risk factors for the development of high blood pressure in pregnancy

If the pregnant woman had high blood pressure in a previous pregnancy or if the occurrence of high blood pressure in pregnancy is known in her family, the risk of developing high blood pressure in the current pregnancy increases. If the uterus is subject to high stretching, such as in twin pregnancies or large babies, high blood pressure is more likely to develop. If the mother already has diabetes mellitus or high blood pressure before pregnancy, the risk of gestational hypertension is also increased.

There are different forms of gestational hypertension

The classification of high blood pressure associated with pregnancy into different forms takes the following aspects into account: If these two questions can be answered in the negative by the pregnant woman and with the help of a urine examination, then uncomplicated gestational hypertension is present. Often young women who are expecting their first child are affected. This form of gestational hypertension is characterised by the fact that neither high blood pressure values existed before the 20th week of pregnancy, nor do the elevated values persist for more than six weeks after birth.

High blood pressure is therefore limited to the time of pregnancy or a six-week phase after the birth of the child. Apart from the elevated blood pressure values, there are no other signs of illness in pregnant women. In the case of so-called pre-eclampsia, the question of protein excretion can be answered with “yes”.

Pregnant women with pre-eclampsia not only have elevated blood pressure values but also a conspicuous urinary finding: they excrete increased amounts of proteins with their urine. This form of high blood pressure during pregnancy can also lead to water retention (edema) in the body. If a persistent rise in blood pressure is detected and an unusually strong weight gain of about 1 kg per week is noticeable or if thick legs (edema) are noticed by the pregnant woman, the doctor should be consulted immediately, as these are signs of pre-eclampsia.

At values of 160/100 mmHg and above, even without oedema or heavy weight gain, a doctor should be consulted to determine the cause of the increased values! Other signs of illness that can occur in connection with pre-eclampsia are persistent headaches, blurred vision or sensitivity to light. – Did the hypertension already exist before pregnancy?

  • In addition to the elevated blood pressure values, can a high amount of proteins in the urine be detected? These complaints should be clarified by a doctor, as serious complications can occur. There may be an undersupply of the child, which one absolutely wants to avoid.

Regular visits to the doctor can help to detect increases in blood pressure or the presence of protein in the urine during pregnancy in good time and to carry out appropriate therapy. Eclampsia and HELLP syndrome are special forms of pre-eclampsia (see below). Chronic hypertension is defined as high blood pressure that occurs before pregnancy or before the 20th week of pregnancy and continues for at least six weeks after birth.

This form of hypertension is therefore not directly related to pregnancy like gestational hypertension and pre-eclampsia with its special forms. The so-called graft gestation is spoken of if the woman already had high blood pressure before pregnancy and this pressure worsens during pregnancy, i.e. even higher blood pressure values are reached. The following table summarises the information once again.

  • Gestational hypertension: high blood pressure due to pregnancy does not cause an increased excretion of proteins with the urine in the last third of the pregnancy
  • High blood pressure caused by pregnancy
  • In the last trimester of pregnancy
  • No increased excretion of proteins with the urine
  • Postpartum remission
  • Pre-eclampsia: high blood pressure is caused by pregnancy; in addition, increased protein excretion in the urine (proteinuria) and fluid accumulation in the tissue (edema formation) must be treated urgently, as without therapy, seizures (eclampsia) and the HELLP syndrome can occur
  • High blood pressure is caused by pregnancy
  • Additionally increased protein excretion in the urine (proteinuria) and fluid accumulation in the tissue (edema formation)
  • Urgent treatment, since without therapy, seizures (eclampsia) and the HELLP syndrome can occur
  • Chronic hypertension: high blood pressure not caused by pregnancy no increased protein excretion in urine detectable
  • High blood pressure not caused by pregnancy
  • No increased protein excretion in urine detectable
  • Kidney disease or high blood pressure already present before pregnancy. Pregnancy leads to a worsening of these pre-existing conditions
  • Kidney disease or high blood pressure already existing before pregnancy
  • The pregnancy leads to a deterioration of these pre-existing conditions
  • High blood pressure caused by pregnancy
  • In the last trimester of pregnancy
  • No increased excretion of proteins with the urine
  • Postpartum remission
  • High blood pressure is caused by pregnancy
  • Additionally increased protein excretion in the urine (proteinuria) and fluid accumulation in the tissue (edema formation)
  • Urgent treatment, since without therapy, seizures (eclampsia) and the HELLP syndrome can occur
  • High blood pressure not caused by pregnancy
  • No increased protein excretion in urine detectable
  • Kidney disease or high blood pressure already existing before pregnancy
  • The pregnancy leads to a deterioration of these pre-existing conditions

There are special forms of high blood pressure during pregnancy: If pre-eclampsia turns into eclampsia, the following symptoms can occur in addition to the elevated blood pressure values and protein excretion in the urine: Eclampsia can also occur after birth. In only 0.1% of cases does preeclampsia turn into eclampsia.

There are various treatment strategies for eclampsia: In the case of an acute seizure, muscle-relaxing drugs such as diazepam (e.g. Valium®) are given and after the seizure, prophylactic therapy with magnesium sulphate is carried out to prevent further seizures. The patient also receives therapy to lower her blood pressure. The baby can be delivered by means of a Caesarean section when the seizure has subsided and the pregnant woman is in a stable condition.

Before and after delivery, she receives therapy to lower her blood pressure and prevent seizures. If the pregnant woman is still in an early phase of pregnancy, after an eclamptic seizure in individual cases a wait-and-see approach may be possible so that the child can be born in a more mature state. Eclampsia can also occur in the postpartum period, i.e. in the period of 6-8 weeks after the birth of the child.

If pain in the right upper abdomen occurs in a pregnant woman who is over the 17th week of pregnancy, a HELLP syndrome should be clarified as the cause. HELLP is derived from the original English name of the disease and describes the symptoms that occur during the course of the disease. The HELLP syndrome is characterised by a combination of an increased breakdown of red blood cells, elevated liver values and a low platelet count.

HE stands for the breakdown of red blood cells (hemolysis), L for elevated liver enzymes and LP for low platelets. These symptoms can lead to a blood clotting disorder and it is possible that the baby is not optimally supplied by the placenta due to the maternal illness. There is an increased risk of developing HELLP syndrome if…

If these symptoms are present, the patient must be monitored immediately in hospital. – severe headaches

  • Flickering before the eyes
  • General discomfort
  • Exaggerated muscle reflexes
  • Seizures
  • And disturbances of consciousness. – the pregnant woman complains of pain in the upper abdomen, especially on the right side.
  • High blood pressure values above 140/90mmHg are measured several times. – Increased protein is excreted with the urine. – the number of platelets in the blood test is reduced.
  • There are signs of the breakdown of red blood cells
  • Increased inflammation values are conspicuous in the blood test. – the baby shows growth retardation in the ultrasound scan. – Eclampsia:High blood pressure Increased protein excretion in the urine (proteinuria) and formation of fluid accumulations in the tissueeurological symptoms: Seizures and unconsciousness
  • High blood pressure
  • Increased protein excretion in the urine (proteinuria) and formation of fluid accumulations in the tissue
  • Neurological symptoms: seizures and unconsciousness
  • HELLP Syndrome:Hypertensive right-sided pain in the upper abdomen Low platelet count, elevated liver values and increased red blood cell breakdown
  • High blood pressure
  • Upper right abdomen pain
  • Low value for blood platelets, increased liver values and increased breakdown of red blood cells
  • High blood pressure
  • Increased protein excretion in the urine (proteinuria) and formation of fluid accumulations in the tissue
  • Neurological symptoms: seizures and unconsciousness
  • High blood pressure
  • Upper right abdomen pain
  • Low value for blood platelets, increased liver values and increased breakdown of red blood cells

Read next article in this series:

All articles in this series:

  1. Gestational hypertension – Is it dangerous?
  2. Risk factors for the development of high blood pressure in pregnancy
  3. Diagnosis
  4. Possible consequences