By Robert Preidt
Pre-eclampsia, which is the development of high blood pressure and elevated protein in the urine during pregnancy, occurs in 3 to 5 percent of pregnancies in developed nations. Left untreated, it can pose serious dangers to both mother and fetus.
Recent research has shown that women with pre-eclampsia are more likely to have high blood pressure after pregnancy, according to the researchers.
"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," said study author Dr. Laura Benschop. She's a researcher in obstetrics and gynecology at Erasmus Medical Center in Rotterdam, the Netherlands.
"We aimed to determine how common it is for women who have pre-eclampsia to have high blood pressure in the year after pregnancy, by looking at more than just their blood pressure readings in the doctor's office," Benschop explained.
Women with severe pre-eclampsia face more than future high blood pressure: They are up to seven times more likely to develop heart disease later in life than those with normal blood pressure during pregnancy, the researchers said.
In the study, Benschop and her colleagues followed 200 women who were diagnosed with severe pre-eclampsia during pregnancy. For one year after pregnancy, the women's blood pressure was monitored day and night (ambulatory readings) and in the clinic.
More than 41 percent of the women had high blood pressure in the year after pregnancy. The most common type (17.5 percent) was masked hypertension, which means normal blood pressure readings in the clinic, but high readings outside of the clinic.
Sustained hypertension occurred in 14.5 percent of the women, and 9.5 percent had white coat hypertension, in which they had higher blood pressure readings at the doctor's office than outside the office.
If only in-clinic readings had been used, 56 percent of women with high blood pressure would have been missed, the researchers noted.
They also found that 46 percent of the women had an insufficient decrease in blood pressure from daytime to nighttime, which is unhealthy, and that 42.5 percent had nighttime hypertension, which increases the risk of heart disease, stroke and death.
The study was published Feb. 5 in the journal Hypertension.
"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 in a journal news release. "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.
"We've shown here that high blood pressure comes in many forms after pregnancy," she concluded. "Women who know their numbers can take the proper steps to lower their blood pressure and avoid the health consequences of high blood pressure later in life."