High blood pressure and pregnancy: Short- and long-term consequences

Highlights

  • A test done mid-pregnancy accurately predicts which women will later develop preeclampsia, a late-pregnancy disorder characterized by high blood pressure and excess protein in the urine. Left untreated, preeclampsia can lead to serious -- even fatal -- complications for a pregnant woman and her baby.
  • Women with high blood pressure during pregnancy risk experiencing high blood pressure, kidney problems, and stroke in the future compared to women with normal blood pressure during pregnancy.

Two studies from the Mayo Clinic presented during the American Society of Nephrology's Annual Kidney Week provide new information related to high blood pressure during pregnancy.

In one study, Vesna Garovic, MD and her team examined the potential of a test done mid-pregnancy to predict which women will later develop preeclampsia, a late-pregnancy disorder that is characterized by high blood pressure and excess protein in the urine and that affects 3% to 5% of pregnancies. Left untreated, preeclampsia can lead to serious -- even fatal -- complications for a pregnant woman and her baby.

Among a group of 315 patients, 15 developed preeclampsia and 15 developed high blood pressure (but not preeclampsia) during pregnancy. All of the patients who developed preeclampsia tested positive in mid-pregnancy for a test that detects the shedding of certain kidney cells called podocytes in the urine. None of those with only high blood pressure tested positive, and none of 44 women with normal pregnancies tested positive. Therefore, this test is highly accurate for predicting preeclampsia, which could alert clinicians to take steps to safeguard against the condition.

In another study, Dr. Garovic's team looked at the long-term health effects of high blood pressure during pregnancy. They identified female residents of Rochester, Minnesota and the surrounding townships in Olmsted County who delivered between 1976 and 1982. The investigators divided the women into two groups -- those with high blood pressure during pregnancy and those without -- and followed them after they reached 40 years of age to monitor their heart and kidney health.

A total of 6,051 mothers delivered between 1976 and1982, and 607 women had high blood pressure at the time while 5,444 did not. After the women reached age 40, women who had high blood pressure during pregnancy were much more likely to experience high blood pressure, kidney disease, and strokes than women who did not have high blood pressure during pregnancy (51% vs 31%, 14% vs 10%, and 8% vs 4%, respectively).

"Studies of the associations of hypertensive pregnancy disorders with maternal risks for future cardiovascular disease could lead to new guidelines for screening and treatment of women at risk, with the ultimate goal of improving cardiovascular health in women," said Dr. Garovic.

Source: American Society of Nephrology