High blood pressure during pregnancy increases a mother’s risk for future cardiovascular disease and death, a new study has found.

Hypertension in pregnancy, or pre-eclampsia, affects between 3 percent and 10 percent of pregnant women in the United States. Left untreated, it can lead to life-threatening complications in both mothers and infants.

The British study, published in Circulation, found 149,712 cases of pre-eclampsia in 1.3 million pregnancies over a 20-year period. The researchers then followed all the women for an average of nine years after they gave birth. Over that time, there were 18,624 first-time cardiovascular events, 65 percent of them in women under 40.

Compared with women who did not have pre-eclampsia, those who did were at higher risk for 12 cardiovascular disorders. They had a 90 percent increased risk for stroke, more than double the risk for heart failure, and two-and-a-half times the risk for heart attack. They were more than four times as likely to have chronic hypertension, and twice as likely as those without pre-eclampsia to die of cardiovascular disease.

“We saw these differences in outcomes as early as one year after the pregnancy,” said one of the study’s senior authors, Fergus P. McCarthy, a consultant obstetrician at the Cork University Maternity Hospital in Ireland. “Any woman affected by hypertension during pregnancy should consult with her physician after she delivers and assure that she has adequate medical follow-up.”