(RxWiki News) Even the smallest quantities of lead can affect the blood pressure of a pregnant woman, according to a recent study from researchers at the Johns Hopkins Hospital.
In a study of 285 pregnant women, researchers found that 25 percent of these women had lead levels greater than 1 microgram (ug) per deciliter (dL) in their umbilical cord blood; that amount is far below the thresholds set by the CDC. Even though the CDC doesn't recommend taking action to reduce lead levels until they reach 5 ug/dL, the pregnant women with more than 1 ug/dL showed significant increases in blood pressure.
According to Lynn Goldman, M.D., M.S., M.P.H., Dean of The George Washington University's School of Public Health and Health Services, the research team was surprised to see that such low levels of lead exposure had such a powerful impact on these women's blood pressure.
Pregnancy, as well as child labor and delivery, already causes high blood pressure in women as the heart has to pump harder to sustain two lives. However, extended periods of high blood pressure during pregnancy (referred to as pregnancy-induced hypertension) can lead to life threatening conditions, putting pregnant women at risk of heart attack later in life. Although Goldman and colleagues observed no relationship between lead exposure and pregnancy-induced hypertension, their findings are still alarming.
As CDC standards for dangerous levels of lead exposure are so far off from the results of this study, the finding that pregnant women's blood pressure rises with small levels of lead exposure should encourage policy makers to revaluate what a safe level of lead exposure is, says Ellen Wells, Ph.D., first author of the study and postdoctoral scholar at Case Western Reserve University School of Medicine.
Approximately six to eight percent of all pregnancies in the United States involve problems with high blood pressure. About 70 percent of those are first-time pregnancies.
The study is published in the journal Environmental Health Perspectives.