Gestational hypertension

This is the medical term used to describe a form of high blood pressure which develops in the 20^th week of pregnancy. This affects around 5 to 10% of all pregnancies and doesn’t usually cause any problems for the mother and baby. In most cases it drops down to normal levels about 6 weeks following the delivery.

What happens if you develop high blood pressure before the twentieth week of pregnancy?

If you have high blood pressure before the twentieth week of pregnancy then it is likely to be ‘primary hypertension’. Basically, this means that you had high blood pressure before you became pregnant - which is also known as ‘pre-existing high blood pressure’.

A normal blood pressure reading is 120/80: if your blood pressure is above this, e.g. 140/90 when taken by the midwife then it means that you have gestational hypertension. Your midwife will take another reading to confirm this diagnosis.

Gestational hypertension can be a warning of pre-existing high blood pressure or pre-eclampsia.

Is high blood pressure common in pregnancy?

It is more common than you realise and even more so in women who are overweight. Being overweight or even obese is a risk factor for high blood pressure.

As an example, if your BMI (Body Mass Index) is 30 or more then you have an increased risk of developing high blood pressure.

Find out more in our causes of high blood pressure section.

Symptoms of gestational hypertension

These include:

• High blood pressure
• Headaches
• Visual disturbances
• Swelling of the hands and face
• Yellowing of the eyes and skin

The effects of gestational hypertension

The earlier you develop gestational hypertension and the more severe it is, the greater the risk to you and your baby. So, you are more likely to have problems with this if you have a very high blood pressure level.

But, most women only develop a mild form of this condition and usually progress through pregnancy in the same way as someone with normal blood pressure.

There is a small risk of needing to be induced or undergo a Caesarean section but many women do deliver a baby as per normal.

Complications of gestational hypertension

It is important to bear in mind that this does increase the risk of pre-eclampsia or other complications such as:

• Stillborn baby
• Intra-uterine growth restriction (low birth weight)
• Premature birth
• Placental abruption (placenta separates before birth)

As a result of this your midwife will keep an eye on your blood pressure throughout your pregnancy. He or she will carry out a few tests such as an ultrasound scan to check upon your baby’s development, blood and urine tests.

Treatment for gestational hypertension

If you have a mild form of this condition then you will be advised to rest and to reduce your salt intake in your diet -if this is high. You may also be advised to make other lifestyle changes.

A mild form does not usually affect the mother or the baby so you can carry on as normal.

But if you have severe gestational hypertension then you will be prescribed medication to lower your blood pressure. Plus your baby will delivered early (induced) to prevent the risk of damage.