WASHINGTON—Phthalates, which are chemicals found in plastics, personal care products and hundreds of other consumer goods, may contribute to high blood pressure in pregnant women, according to a study published in the Journal of the Endocrine Society.
Hypertensive disorders of pregnancy such as preeclampsia are a leading cause of maternal mortality in the United States. Higher blood pressure during pregnancy has been linked to adverse health outcomes in both the mother and child.
While factors such as family history and lifestyle are known to increase risk, growing evidence suggests that exposure to phthalates—chemicals commonly found in consumer products that can interfere with the body's natural hormones—may also contribute to elevated blood pressure during pregnancy.
"Our study suggests that having higher concentrations of personal care products-associated chemicals, known as phthalates, in the body might contribute to elevated blood pressure in pregnancy," said Kimberly Parra, Ph.D., of Harvard T.H. Chan School of Public Health in Boston, Mass. "While our study does not show that phthalates cause high blood pressure during pregnancy, it suggests that reducing exposure to this class of chemicals by limiting personal care products containing these ingredients, particularly those with fragrance, may be a way to address high blood pressure in pregnancy and improve pregnancy health."
The researchers measured phthalate exposure and blood pressure in 338 pregnant women from The Environmental Reproductive and Glucose Outcomes (ERGO) Study at three points during pregnancy. They analyzed whether higher levels of these chemicals—individually and in combination—were linked to higher blood pressure or an increased risk of pregnancy-related high blood pressure disorders.
The authors found that pregnant women with higher urine concentrations of fragrance-associated phthalates and those in personal care products had higher systolic and diastolic blood pressure markers of an increased risk of hypertensive disorders of pregnancy.
About 13% of participants in the study developed a pregnancy-related high blood pressure disorder. Women with higher levels of certain phthalates, especially those found in personal care products, tended to have higher blood pressure later in pregnancy.
"More research is needed to better understand these findings, particularly whether the effects are driven by changes in estrogen-related pathways. Additional studies should also examine the potential role of other phthalates and their replacement chemicals," Parra said.
Other authors are Emma Preston, Marlee Quinn, Paige Williams, and Tamarra James-Todd of Harvard T.H. Chan School of Public Health; Michele Hacker and Blair Wylie of Beth Israel Deaconess Medical Center and Harvard Medical School; Thomas McElrath of Harvard T.H. Chan School of Public Health and Harvard Medical School; David Cantonwine, Camille Powe and Ellen Seely of Harvard Medical School in Boston, Mass.; Antonia Calafat and Julianne Cook Botelho of the Centers for Disease Control and Prevention in Atlanta, Ga.
The study was funded by the National Institute of Environmental Health Sciences, the National Institute of Diabetes and Digestive and Kidney Diseases, the Eunice Kennedy Shriver National Institute of Child Health and Human Development, the National Center for Advancing Translational Sciences, the Robert Wood Johnson Foundation's Harold Amos Medical Faculty Development Program, and the Massachusetts General Hospital Claflin Distinguished Scholar Award.
"Associations of Urinary Phthalate Metabolite and Replacement Chemical Concentrations with Gestational Blood Pressure" was published online.
