The study adds to growing evidence, all pointing to pregnancy as a "proving ground," says Mark Mallinger, MD, professor of obstetrics and gynecology at the University of Pittsburgh Medical Center Magee-Womens Hospital. Mallinger was not associated with the study but agreed to discuss its findings with WebMD.
"Pregnancy is definitely a significant stressor -- if you can get through it OK, you won't likely have certain health problems later," he tells WebMD. Indeed, "pregnancy has been shown to predict diabetes, mood disorders, and heart disease later in life. This study is more evidence that women who have pregnancy-induced hypertension have double the risk of hypertension later."
Women with preeclampsia have high blood pressure and protein in their urine, and preeclampsia can kill both the mother and unborn child if not treated. Since delivery almost always resolves the condition, doctors often deliver the child early. Pregnancy-induced hypertension is also usually resolved by delivery.
However, a mother's blood pressure worries aren't over once the baby is born, as this study shows.
The Scottish study focuses on women living in the city of Aberdeen, "a fairly stable population -- people don't stray too far away from here," says lead researcher Cairns S. Smith, PhD, with the University of Aberdeen.
Smith and colleagues analyzed a database of 2,790 pregnancies in the Aberdeen area since 1951, specifically identifying women who had developed either pregnancy-induced hypertension or preeclampsia. Researchers managed to track down nearly 75% of the women in 1997 -- some 40 years later for many, he tells WebMD.
"There's been some uncertainty whether there were long-term effects from pregnancy-induced hypertension," says Smith. Also, most studies depended on women's recall of details of their pregnancy, which may not have been accurate.
In their analysis of hospital admissions, Smith's group found that women who had pregnancy-induced hypertension or preeclampsia were at increased risk of hypertension, stroke, and ischemic heart disease (blocked arteries to the heart) later in life.
The data: 41% of the women who had pregnancy-induced hypertension and 49% of the women with preeclampsia were diagnosed with hypertension later in life, compared with 27% of women without these conditions.
The main message: "We need greater awareness of the risks of [pregnancy-induced] hypertension and preeclampsia," Smith tells WebMD. "Women need to know they are likely to have problems with blood pressure later in life and need to be getting it checked regularly and treated."