High blood pressure in mothers while they are pregnant can lead to negative effects in her offspring’s thinking skills which may carry through until they are much older, according to a study published online in Neurology, the journal of the American Academy of Neurology.

Katri Räikönen, PhD, from the University of Helsinki in Finland explained:

“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. 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.”

During the study, medical histories of 398 men’s mothers’ blood pressure were analyzed. All of the men were born to the women between the years 1934 and 1944. At the age of 20, the men had their thinking skills examined, and once again when they were around the age of 69. The examinations on the men involved math reasoning, visual and spatial relationships, and language skills.

According to the report, the men whose moms had high blood pressure when they were pregnant received scores that were 4.36 points less on thinking ability tests when they were 69 years than those whose mothers did not have high blood pressure.

The men whose mothers had high blood pressure also scored lower when they were 20 years old, and had a greater decline in their scores over the years than the individuals whose mothers had not been hypertensive. The evidence was most strongly related to math reasoning.

The experts looked into whether premature birth at all influenced these results and determined that it did not. The babies’ fathers professions – anywhere from a manual laborer to an office worker – also did not alter the findings.

In an Abstract in the journal, the authors concluded: “Maternal hypertensive disorders in pregnancy predict lower cognitive ability and greater cognitive decline up to old age. A propensity to lower cognitive ability and decline up to old age may have prenatal origins.”

Hypertension is a common medical problem encountered by pregnant mothers. Approximately 3% of all pregnant mothers develop hypertension. There are four types of hypertensions in pregnancy, according to the National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy:

  • Chronic hypertension – blood pressure exceeds 140/90 mm Hg before the mother became pregnant, or before her 20th week of pregnancy.
  • Preeclampsia – there is a sharp rise in blood pressure and leakage of albumin into the urine. Albumin is a protein. The hands, feet and face swell. Preeclampsia is the most common complication of pregnancy and usually occurs in the third trimester. It is more common in first pregnancies and, is more prevalent in females with diabetes or mothers who are carrying twins. A woman whose mother had preeclampsia when pregnant has a higher risk of developing it herself.
  • Preeclampsia superimposed on chronic hypertension.
  • Gestational diabetes – diabetes that clears up after the baby is born. In most cases of gestational diabetes, the mother suffers from hypertension.

Some associations and societies class hypertension in pregnancy into just two categories: 1. Preexisting hypertension – hypertension which was already there before the mother became pregnant. 2. Gestational hypertension – high blood pressure that occurs only during pregnancy. Preeclampsia can be added to either category.

Written by Christine Kearney