High blood pressure during pregnancy is a key component of a condition called pre-eclampsia, but a new study shows that women affected by this condition are also at risk of having high blood pressure after the baby is born.
"The problem is high blood pressure after pregnancy often goes unnoticed because many of these women have normal blood pressure readings in the doctor's office," explained Laura Benschop, MD. "We aimed to determine how common it is for women who have pre-eclampsia to have high blood pressure in the year after pregnancy.”
In addition to high blood pressure, women with pre-eclampsia have elevated protein in the urine. Approximately four percent of all pregnancies in the developed world are pre-eclamptic. Factors that increase the risk of pre-eclampsia include first pregnancies, previous experience with pre-eclampsia, having relatives who’ve experienced pre-eclampsia, and carrying multiple babies. Pre-eclampsia can prevent the placenta from getting enough blood, which runs the risk of the baby receiving inadequate supply of oxygen and food, which can result in low birth weight.
In the new study, Benschop and other researchers recruited 200 women who had experienced pre-eclamptic pregnancies. Researchers followed each participant for one year following her pregnancy, monitoring blood pressure day and night.
The study yielded several interesting findings. First, around 41 percent of all participants had high blood pressure in the year following pregnancy, and masked hypertension was the most common form. This is where individuals have normal blood pressure in the doctor’s office but high blood pressure at home. Researchers estimate that 56 percent of high blood pressure cases would have been missed if the study didn’t include blood pressure monitoring outside of the doctor’s office.
Increasing the awareness of high blood pressure after pregnancy could help women actively take steps to address it, reducing their risk of heart disease later in life.
"Our findings suggest women who have high blood pressure during pregnancy should continue to monitor their blood pressure long after they've delivered their babies,” Benschop said. “It's not only important to monitor blood pressure in the doctor's office, but also at different times of the day and night, at home.”
The present study was published in the journal Hypertension.