Women who experience high blood pressure during pregnancy are more likely to develop heart disease and heart failure in later life, warn researchers.
Published in the Journal of the American Heart Association, the study found that women who experienced high blood pressure during their first pregnancy were at 45 per cent higher risk of overall cardiovascular disease.
“When we looked at all the available research, the answer was clear: women who develop high blood pressure during pregnancy are more likely to develop several different kinds of cardiovascular disease,” said senior author Dr Clare Oliver-Williams from the University of Cambridge in the UK.
Between one to six per cent of all pregnancies in Western countries are affected by high blood pressure, which usually returns to normal after giving birth, the study said.
This condition is known as gestational hypertension or pregnancy-induced hypertension. It differs from pre-eclampsia in that traces of protein are not found in the urine.
Clinicians increasingly recognise that women who have had gestational hypertension are more likely to develop cardiovascular disease in later life.
However, studies of different kinds of cardiovascular diseases, such as heart disease and heart failure, have found mixed results.
To examine these links further, an international team of researchers conducted a systematic review and meta-analysis of 21 studies involving a total of 3.6 million women, 128,000 of who previously had gestational hypertension.
The researchers found that women who experienced high blood pressure during their first pregnancy were at 46 per cent higher risk of coronary heart disease compared to women who did not have high blood pressure in pregnancy.
Women with one or more pregnancies affected by high blood pressure were at 81 per cent higher risk of cardiovascular disease, 83 per cent higher risk of coronary heart disease and 77 per cent higher risk of heart failure.
The study adds to growing evidence of the relationship between pregnancy and subsequent risk of cardiovascular events.
Recurrent miscarriages, preterm birth, foetal growth restriction and pre-eclampsia have all previously been linked with a greater risk of heart disease.
The researchers said that it is not entirely clear why gestational hypertension is associated with heart disease in later life.
However, they suggest it may be that high blood pressure in pregnancy causes lasting damage that contributes to cardiovascular disease.
