OHSU

Children Born to Mothers With Preeclampsia Are at Increased Risk for Stroke Later in Life

03/24/09  Portland, Ore.

Study suggests preeclampsia damages blood vessels in the baby’s brain

It’s been shown that women who develop preeclampsia are at increased risk of cardiovascular disease later in life, and that their babies have higher blood pressure during childhood. What hasn’t been known are the long-term health risks for these children. A recent study by Oregon Health & Science University researchers found these children are at increased risk for stroke later in life.

 

Preeclampsia in pregnancy is characterized by high blood pressure and protein in the urine. Without proper care, the condition can lead to serious complications, including death, for both mother and baby.

Kent Thornburg, Ph.D., and David Barker, M.D., Ph.D., both of the OHSU Heart Research Center, collaborated with Eero Kajantie, M.D., at the National Public Health Institute in Finland and reviewed the maternity records of 6,410 singleton babies born in Helsinki between 1934 and 1944. They found 284 of the pregnancies were complicated by preeclampsia and another 1,592 were complicated by gestational hypertension. 

Using the personal identification number of each of the offspring, the researchers then identified deaths and hospital discharges for cardiovascular disease and stroke among them between 1973 and 2003, 40 to 70 years later. They found 272 of the offspring had experienced a stroke, including 100 offspring of mothers whose pregnancies were complicated by either preeclampsia or gestational hypertension.

“This is the first study we are aware of that has been able to follow the offspring from pregnancies complicated by preeclampsia into their later lives,” said Thornburg, professor of medicine (cardiovascular medicine) in the OHSU School of Medicine and director of the OHSU Heart Research Institute. “We wouldn’t have been able to do this research without the amazingly detailed records of the Helsinki Birth Cohort Study, which was established 15 years ago by professor Johan Eriksson, a co-author on this paper. We believe this information applies to women the world over.”

The study also found that babies born to mothers with preeclampsia had lower birth weight and smaller than average head circumference, while babies born to mothers with gestational hypertension had larger than average head circumference and a higher ratio of head circumference to length. The researchers concluded that under-nutrition of the fetus in women with preeclampsia may lead to reduced brain growth and ultimately stroke. They speculate that in mothers with gestational hypertension who had babies with lower birth weights, but larger head circumferences, the growth of the brain may have been protected at the expense of the growth of the body. The researchers suggest such fetal brain-sparing responses may permanently change the structure of the cerebral arteries.

Based on the findings, the researchers speculate that stroke may originate in one of two ways, either through reduced brain growth or impaired brain growth leading to brain-sparing responses.

“This research helps us move away from current thoughts about how strokes form,” said Barker, who is also a professor of epidemiology at the University of Southhampton, United Kingdom. “This work is further evidence that stroke begins in the womb.”

The study is currently published online and will be in the April edition of Stroke. The research was funded by the British Heart Foundation, and several Finnish medical societies and foundations.