Maternal Blood Lead Levels and the Risk of Pregnancy-Induced Hypertension: The EDEN Cohort Study

Abstract

BackgroundPrior studies revealed associations of environmental lead exposure with risks of hypertension and elevated blood pressure.ObjectiveWe examined the effect of blood lead levels on blood pressure and the incidence of pregnancy-induced hypertension (PIH) in the second and third trimesters of pregnancy.MethodsOne thousand seventeen pregnant women were enrolled in two French municipalities between 2003 and 2005 for the EDEN (Etude des Déterminants pré et post natals du développement et de la santé de l′ Enfant) cohort study. Blood lead concentrations were measured by atomic absorption spectrometry in mothers between 24 and 28 weeks of gestation.ResultsPIH was diagnosed in 106 subjects (10.9%). Age, parity, weight gain, alcohol, smoking habits, and calcium supplementation were comparable between hypertensive and nonhypertensive women. Lead levels were significantly higher in PIH cases (mean ± SD, 2.2 ± 1.4 μg/dL) than in normotensive patients (1.9 ± 1.2 μg/dL; p = 0.02). Adjustment for potential confounder effects slightly attenuated but did not eliminate the significant association between blood lead levels and the risk of PIH (adjusted odds ratio of PIH = 3.3; 95% confidence interval, 1.1–9.7). We also observed geographic differences in lead exposure and in the incidence of PIH and found significant correlations between blood lead levels and unadjusted as well as adjusted systolic and diastolic blood pressures after 24 weeks of gestation.ConclusionsThese findings confirm the relationship between blood lead levels at mid-pregnancy and blood pressure and suggest that environmental lead exposure may play an etiologic role in PIH.

The effects of low-level prenatal lead exposure on birth outcomes

“…As shown in Table 1, the median level of maternal blood lead in the study was 3.20 mg/dL (range: 1.00e11.91 mg/dL), slightly higher than the reference data from the NHANES study from 1999 to 2002 (for participants 20 years and older, geometric mean: 1.52 mg/dL; n ¼ 4525) (Crinnion, 2010) and from a cohort study in France (mean maternal blood lead level: 1.9 mg/dL; n ¼ 1017) (Yazbeck et al, 2009). However, the pregnant women in our study had much lower levels of lead exposure compared to the reference data from previous domestic studies of pregnant women from Chengdu (mean: 5.57 mg/dL; n ¼ 128) (Jiang et al, 2011) and Shanghai (mean: 5.61 mg/dL; n ¼ 400) (Zhu et al, 2011).…”

The Influence of Arsenic, Lead, and Mercury on the Development of Cardiovascular Diseases

“…2) [60]. For many years, the relationship of lead exposure and high blood pressure was studied in battery, ceramic, pigment, re�nery, and smelter industries [57].…”

Lead Exposure in Female Workers Who are Pregnant or of Childbearing Age

“…For instance, pregnant rats administered 200 mg/l lead in drinking water, resulting in a peak blood lead of 60-80 µ g/dl, showed a developmental delay in the fetal cerebral cortex 52) . Lead not only adversely influences the nervous system, but also has many other effects including defects in hematopoietic and renal impairment, pregnancy induced hypertension/pre-eclampsia, spontaneous abortion, alteration of fetal anthropometric characteristics and birth weight, and preterm labor [57][58][59][60][61][62] . In addition, women exposed to lead at work before pregnancy have increased rates of miscarriages, stillbirths, and low birth weight infants 63) .…”