October 4, 2012

High Blood Pressure In Pregnancy May Curb Child’s IQ

Connie K. Ho for redOrbit.com — Your Universe Online

Researchers from the American Academy of Neurology recently found that a mother´s high blood pressure during pregnancy could impact a child´s cognitive skills long into adulthood.

The findings of the study were recently published in the online version of Neurology, the medical journal of the American Academy of Neurology.

"High blood pressure and related conditions such as preeclampsia complicate about 10 percent of all pregnancies and can affect a baby's environment in the womb," explained the study´s author Katri Räikönen, a professor at the University of Helsinki in Finland.

"Our study suggests that even declines in thinking abilities in old age could have originated during the prenatal period when the majority of the development of brain structure and function occurs."

In the study, the researchers examined medical records from the mothers of 398 men who were born between 1934 and 1944. Along with identifying the mothers´ blood pressure, the scientists tested the men´s thinking abilities at age 20 and again at around 69 years of age. They also compiled data on the participants´ language and math skills as well as visual and spatial relationships.

The team of investigators discovered that the men whose mothers had high blood pressure scored about 4.36 points lower on the tests than the men whose mothers did not have high blood pressure. At both ages 20 and age 69 these men score lower than their counterparts. Their scores also tended to decline more quickly over time than the men whose mothers did not have high blood pressure.

“Maternal hypertensive disorders in pregnancy predict lower cognitive ability and greater cognitive decline up to old age,” noted the researchers in an article by the Daily Mail. “A propensity to lower cognitive ability and decline up to old age may have prenatal origins.”

Furthermore, the researchers studied whether premature birth would impact the findings and found that early birth did not affect the score in the same way. Additionally, the father´s occupation did not appear to influence the participants´ scores, and the scores did not change for participants whose fathers worked as manual laborers or office workers.

Overall, researchers believe the results of the study fill in another puzzle piece in the attempt to understand the affects of a mother´s health on the physical and mental health of her offspring.

"We weren't surprised, given that prematurity and low birth weight are associated with lower cognitive [mental] ability, and maternal hypertensive disorders are one of the main reasons for prematurity and low birth weight,"  Räikönen told U.S. News.

"I could say it would have been more surprising not to find an association. Of course, this study adds to the existing literature by showing that the effects persist into old age."

Other medical professionals believe that further researcher is needed that uses a larger sample of subjects and includes participants of different ethnic backgrounds.

"I would caution my patients that they don't need to be alarmed at this stage," commented Dr. Jennifer Wu, an obstetrician-gynecologist at Lennox Hill Hospital in New York City.

"We don't have enough information to tell them their daughter or son is going to have impaired cognitive [mental] function in 65 years. It's an interesting study, but I think there's already enough for parents to worry about in pregnancy and the first year of life."