Skip the main content if you do not want to read it as the next section.
New research into high blood pressure disorders in pregnancy
Two important new studies examine the long-term health of women with high blood pressure disorders during pregnancy
This July the BMJ (British Medical Journal) published two important new studies looking into the effect of hypertension (high blood pressure) disorders during pregnancy. The medical profession has become more and more aware of the importance of keeping a close eye on the blood pressure and heart health of women who have had such disorders, and these studies add to that understanding.
Hypertension disorders during pregnancy include:
- gestational hypertension, also known as pregnancy-induced hypertension, when blood pressure becomes high during pregnancy
- pre-eclampsia, which causes high blood pressure and protein in the urine during pregnancy, it is usually mild but can lead to more serious problems if left untreated
- eclampsia, a serious condition which can develop from pre-eclampsia, it causes fits (seizures) in the mother and can affect the baby
- HELLP syndrome, a rare liver and blood-clotting disorder that can affect pregnant women.
The Danish study of 1 million people
The first study looked at over a million women in Denmark to find out whether a hypertension disorder in pregnancy affected their risk of high blood pressure later in life, and how their risk evolves over time.
They found that women who had a hypertension disorder during pregnancy were up to three times more likely to have high blood pressure 10 years after giving birth than women who didn’t. Their risk was at its highest in the first year after giving birth, and was still twice as high up to 20 years later.
What the Danish study tells us
High blood pressure can lead to a number of serious health problems including heart disease and stroke. It was already known that women with a hypertension disorder in pregnancy have a higher risk of high blood pressure later on, but the way this risk changes over time wasn’t clear, making it hard to make recommendations for their follow up care.
This study gives a clearer picture of when the risk of high blood pressure goes up, and how this risk changes over time. It tells us that women with affected pregnancies should have their blood pressure monitored in the long term, and that it needs to begin soon after pregnancy, so that it can be brought down if needed.
The Nurses’ Health Study II
In this study of over 50 000 nurses in the US, the researchers set out to understand how lifestyle factors affect women’s risk of high blood pressure later in life and how this is affected by a hypertensive disorder in pregnancy.
Being overweight or obese was the only lifestyle factor linked to long-term high blood pressure. Higher body mass index (a measure of being overweight) also raised the risk of long term high blood pressure in women who had had a hypertensive disorder in pregnancy. The effect of salt intake, potassium intake, physical activity and the DASH diet wasn’t clear.
This suggests that sticking to a healthy lifestyle, that helps to maintain a healthy weight, could lower the risk of long-term high blood pressure, especially for women who have had a hypertension disorder in pregnancy.
What the Nurses’ study tells us
It is already known that a healthy lifestyle can lower the risk of high blood pressure in the general population. This study tells us that being a healthy weight, and living a lifestyle that supports that, is even more important for women who had a hypertension disorder in pregnancy than those who haven’t. The authors also found that women who had diabetes during pregnancy should be supported in keeping to a healthy weight after pregnancy.
Katharine Jenner, CEO of Blood Pressure UK, says: these studies show that hypertension disorders during pregnancy put women at risk of high blood pressure and its related diseases later on in life. It’s vital that their blood pressure continues to be monitored in primary care so that they can be given the right support to keep it under control, whether that’s with lifestyle advice or medications.
Our Winter issue of Positive Pressure will include an article by Professor Gareth Beevers, Professor of Medicine and one of our Trustees, for women who have high blood pressure before becoming pregnant. Become a member to receive Positive Pressure twice a year and a host of other benefits.