You may have heard that early life environment can affect children’s health, but exactly how it affects may not be clear to you. According to a new study, the environmental factors of a pregnant mother can impact whether her child is prehypertensive or hypertensive during childhood.

Exposure to negative lifestyle factors in pregnancy, such as obesity, physical inactivity, poor diet, and alcohol and tobacco consumption have long been established as heart disease risk factors for mothers.
These years, however, researchers also found that these risk factors are linked with prehypertensive status in children and their likelihood of developing hypertension (high blood pressure) later in life.

How the study went
The researchers collected data from 1,277 mother-child pairs from the Human Early-Life Exposome (HELIX) project, which contains data from 6 European countries including the United Kingdom, France, Spain, Lithuania, Norway and Greece.
Researchers collected blood and urine samples from the selected children aged between 6 to 11 with no prior health problems. At the time of the examination, 10% of the children were classified as prehypertensive or hypertensive.

89 prenatal maternal exposures and 128 postnatal child exposures were evaluated, among which 4 broader environmental factors were determined to influence blood pressure status in children:
Built environment (where the mother was living during pregnancy)
Outdoor temperature
Fish intake
Exposure to chemicals

"This study is the first to simultaneously consider the possible effects of exposure to hundreds of environmental factors during early life on blood pressure in children," said Charline Warembourg, main author of the study.
"Exposures were assessed through a mix of predictive modeling from home address and questionnaire and through determination of biological samples from the mother and child."
What you need to avoid
According to the study results, here are some suggestions for pregnant mothers' and their children’s health both:
Living in a walkable environment
Living in a walkable environment, with access to green spaces, shops, restaurants and public transportation was linked to a normal blood pressure in children. By contrast, the mothers who did not live in an urban or highly walkable environment had higher blood pressure. Researchers believed the lower blood pressure was associated with higher amount of physical activity during the pregnancy.

Exposure to a higher outdoor temperature
Pregnant mothers who were exposed to higher outdoor temperature tended to have children with lower diastolic blood pressure. Outdoor temperature has been proven in previous studies to be a known environmental factor to affect blood pressure in both adults and children.
Fish intake
Both low and high fish intake during pregnancy were associated with an increase in blood pressure in children. Although the omega-3 fatty acids in fish are beneficial for overall cardiovascular health, the chemicals or metals contained in the fish could reduce any positive effects of omega-3 fatty acids.

Exposure to certain chemicals in plastics, cosmetics, household cleaners or clothing
A chemical called bisphenol-A (BPA) that can be found in various consumer plastics, and perfluorooctanoate (PFOA) concentrations, which can be found in cosmetics, household cleaners or clothing, can lead to higher blood pressure in children. Checking the chemicals contained before purchasing these products can help reduce the risk.