High blood pressure in pregnancy: when is it dangerous?

High blood pressure in pregnancy (hypertension) is defined as systolic blood pressure (commonly called maximum) above 140 mm Hg and diastolic blood pressure (commonly called minimum) above 90 mm Hg.

The pressure indicates precisely the pressure that the blood has inside the veins, and if this pressure is higher than the safety threshold, it can cause serious health problems, especially during pregnancy.

Sometimes high blood pressure is present before pregnancy. In other cases, hypertension develops during pregnancy.

Gestational hypertension

Women with gestational hypertension experience high blood pressure after 20 weeks of pregnancy. There is typically no increased protein in the urine or other signs of organ damage. Some women with gestational hypertension can develop preeclampsia .

Chronic hypertension

Chronic hypertension is high blood pressure that is present before pregnancy or occurs before 20 weeks of pregnancy. Because high blood pressure usually has no specific symptoms, it can be difficult to determine when it started.

Chronic hypertension with superimposed preeclampsia.

This condition occurs in women with chronic hypertension before pregnancy who experience worsening hypertension, and the presence of protein in the urine or other complications, related to high blood pressure during pregnancy.

Preeclampsia

Preeclampsia occurs when high blood pressure occurs after 20 weeks of pregnancy and is associated with involvement of other organs, including the kidneys, liver, blood, or brain. Untreated preeclampsia can lead to serious — even fatal — complications for the mother and baby, including the development of seizures (eclampsia).

Until recently, preeclampsia was only diagnosed if a pregnant woman had high blood pressure and protein in her urine. Experts recently confirmed that it is possible to have preeclampsia without having protein in your urine.

Effects of hypertension in pregnancy

High blood pressure during pregnancy carries various risks, including:

• Decreased blood flow to the placenta a. If the placenta doesn’t get enough blood, the baby may be getting less oxygen and nutrients. This can lead to slow growth ( intrauterine growth restriction ), low birth weight, or premature birth . Prematurity can lead to breathing problems, an increased risk of infection, and other complications for the baby.
• Placental abruption : Preeclampsia increases the risk of this condition in which the placenta separates from the inner wall of the uterus before delivery. The consequences can also be serious for both mother and baby.
• Intrauterine growth restriction : High blood pressure can cause the baby to grow slowly or impaired (intrauterine growth restriction).
• Injury to other organs : Poorly controlled high blood pressure can cause injury to the brain, heart, lungs, kidneys, liver, and other major organs. In severe cases, it can be life-threatening.
• Premature birth : Sometimes it may be necessary to plan an early birth to prevent life-threatening complications
• Future cardiovascular disease : Having preeclampsia could increase your risk of future cardiovascular disease.

How to know if you have high blood pressure during pregnancy?

During pregnancy it is important to monitor your blood pressure frequently, either in the doctor’s office or at home, preferably at the same time of day.

The following cases are distinguished:

•  Elevated blood pressure:  This is when systolic blood pressure ranges from 120 to 129 millimeters of mercury (mm Hg) and diastolic blood pressure is below 80 mm Hg. Raised blood pressure tends to get worse over time unless steps are taken to control blood pressure.
• Stage 1 hypertension : Systolic blood pressure is between 130 and 139 mm Hg, and diastolic blood pressure is between 80 and 89 mm Hg.
• Stage 2 hypertension : Systolic blood pressure is 140 mm Hg or higher and diastolic blood pressure is 90 mm Hg or higher.

After 20 weeks of pregnancy, blood pressure above 140/90 mm Hg – documented on two or more occasions, at least four hours apart, with no other organ damage – is considered gestational hypertension.

In the case of chronic or gestational hypertension, the number of controls is increased and it will be necessary to undergo frequent blood and urine tests. There will also be an increase in ultrasound checks to assess the child’s well-being and growth.

Can you take medicines to lower blood pressure?

Some blood pressure medications are considered safe to use during pregnancy, but angiotensin converting enzyme (ACE) inhibitors, angiotensin II receptor blockers, and renin inhibitors are generally avoided during pregnancy. Treatment should be discussed with your referring physician. Your doctor will prescribe the safest drug at the most appropriate dose and take it exactly as prescribed.

If I suffer from hypertension what should I do to prepare for pregnancy?

A woman who has high blood pressure should, in the preconception phase , make an appointment for a visit to the gynecologist who will follow her pregnancy. You should also discuss finding a pregnancy with the doctor (cardiologist or other) who treats you for the management of your high blood pressure. Doctors will evaluate the woman’s health and, by mutual consent, may change the therapy in anticipation of pregnancy.

If the woman is overweight, it is generally recommended that she lose the excess pounds before trying to conceive.

 Will I be able to breastfeed the baby?

Breastfeeding is encouraged for most women who have high blood pressure, even those on medications. In any case, the dosage and type of drug to be taken should be discussed with your doctor.