Relationship between risk factors for infertility in women and lead, cadmium, and arsenic blood levels: a cross-sectional study from Taiwan Original paper

What was studied?

This cross-sectional study investigated the association between blood concentrations of lead (Pb), cadmium (Cd), and arsenic (As) and risk factors for infertility in women of childbearing age in Taiwan. The study aimed to elucidate whether exposure to these environmental toxic metals, commonly found as contaminants in the environment and traditional Chinese herbal medicines, correlates with infertility. Researchers compared the levels of Pb, Cd, and As in blood samples of infertile and pregnant women and examined how lifestyle factors, including use of Chinese herbal medicine, alcohol consumption, and physical activity, might influence metal body burdens. Additionally, the study assessed possible associations between blood metal levels and reproductive hormone concentrations (FSH, LH) in the infertile group.

Who was studied?

Three hundred and sixty-seven women aged 18–45 years were recruited from the Department of Obstetrics and Gynecology at Taiwan Adventist Hospital between 2008 and 2010. Of these, 310 infertile women (defined as failing to conceive after one year of regular intercourse) and 57 pregnant women (confirmed by ultrasound in the first trimester) were included after applying exclusion criteria (e.g., excluding women with PCOS, diabetes, IVF pregnancies, and other confounders). Sociodemographic data, lifestyle habits, and reproductive histories were collected via structured interviews. Blood samples for metal and hormone analyses were collected under standardized conditions, ensuring comparability between the groups.

Most important findings

The study found that blood levels of Pb and As, but not Cd, were significantly higher in infertile women compared to pregnant women. Median Pb concentrations were 15.7 μg/L in infertile versus 11.6 μg/L in pregnant women; As levels were also higher in the infertile group. Use of Chinese herbal medicine was more prevalent among infertile women and was associated with higher blood Pb levels in both infertile and pregnant women, with a clear dose-response relationship: more frequent herbal medicine use correlated with greater Pb burden. Alcohol consumption was also higher among infertile women, while regular physical activity was more common in pregnant women. Physical activity showed a trend toward reducing blood Pb accumulation. No significant correlations were observed between blood metal concentrations and reproductive hormone levels in infertile women, potentially due to overall metal exposures being below recognized toxicity thresholds.

Key implications

This study highlights that environmental and lifestyle exposures to heavy metals may contribute to increased Pb body burden in women of childbearing age, potentially impacting fertility. While the absolute metal levels observed were below acute toxicity thresholds, the data support the need for caution regarding the use of herbal preparations that may contain heavy metals, especially for women planning pregnancy. Regular physical activity may have a protective effect against Pb accumulation. Clinicians should consider environmental and cultural factors when assessing infertility and counsel patients on potential risks associated with traditional medicine use. These findings underscore the importance of monitoring metal exposures and integrating environmental health perspectives into reproductive care.