Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. 
Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. What was studied?
This original case-control study investigated the relationship between pregnancy complications and nickel (Ni) content in the maternal-fetal system, focusing on maternal blood, placental blood, and umbilical cord blood. The research was conducted in Kunming, Yunnan Province, China, where 72 pregnant women were recruited and divided into two main groups: a control group (healthy pregnancies) and a disease group (those with gestational diabetes mellitus [GDM], hypertensive disorder complicating pregnancy [HDCP], or both). The primary objectives were to quantify Ni exposure in pregnant women, evaluate the distribution of Ni across maternal, placental, and fetal compartments, and assess placental barrier function in the context of pregnancy complications. Using inductively coupled plasma mass spectrometry, the researchers measured Ni concentrations in biological samples collected immediately after delivery. Their analysis aimed to clarify whether pregnancy complications compromise the protective role of the placenta, potentially increasing fetal exposure to Ni and associated health risks.
Who was studied?
The study population comprised 72 pregnant women, all over 18 years of age, who gave birth at The First People’s Hospital of Yunnan Province during 2019. Exclusion criteria included recent migration to the study area, smoking, alcohol consumption, or a history of occupational heavy metal exposure. The participants were divided into four subgroups: 29 healthy controls, 14 with GDM, 13 with HDCP, and 16 with both GDM and HDCP. All participants provided written informed consent, and data on maternal characteristics (age, body mass index [BMI], pregnancy history, environmental exposures) and neonatal outcomes (birth weight, length, Apgar scores) were collected via questionnaires and hospital records. This well-defined population allowed the researchers to control for confounding variables and focus on the influence of gestational disease status on Ni transfer and accumulation.
Most important findings
| Aspect | Findings / Details |
|---|---|
| Placental Barrier Function | HDCP or GDM+HDCP groups had higher umbilical cord Ni; overall disease group: 60.47% had a favorable maternal-to-cord ratio; lowest in HDCP subgroup. |
| Control Group | Placenta limited fetal Ni exposure; umbilical cord blood Ni lower than maternal blood; 85% had maternal-to-cord Ni ratio >1 (effective barrier). |
| Disease Groups | Newborns in the HDCP group had lower birth weights and Apgar scores, indicating possible adverse effects from elevated fetal Ni exposure. |
| Birth Outcomes | Newborns in HDCP group had lower birth weights and Apgar scores, indicating possible adverse effects from elevated fetal Ni exposure. |
| Environmental Exposure | Ni levels below international standards but still led to measurable fetal transfer and potential health risks in gestational disease contexts. |
Key implications
These findings have significant implications for heavy metal certification and public health regulation. The study shows that even low-level environmental Ni exposure can threaten fetal health in pregnancies complicated by impaired placental barrier function, emphasizing the need for stricter monitoring and exposure limits, particularly in women with GDM or HDCP. For the HTMC program, the results support incorporating pregnancy complication status into risk assessments. They also underscore the importance of environmental and occupational interventions to reduce Ni exposure during pregnancy and the ongoing surveillance of maternal and neonatal heavy metal levels. These insights inform the development of targeted guidelines and certification standards for vulnerable populations to improve fetal health outcomes.
Citation
Ding AL, Hu H, Xu FP, Liu LY, Peng J, Dong XD. Pregnancy complications effect on the nickel content in maternal blood, placenta blood and umbilical cord blood during pregnancy. World J Clin Cases. 2021;9(28):8340-8348. doi:10.12998/wjcc.v9.i28.834
Heavy metals are high-density elements that accumulate in the body and environment, disrupting biological processes. Lead, cadmium, arsenic, mercury, nickel, tin, aluminum, and chromium are of greatest concern due to persistence, bioaccumulation, and health risks, making them central to the HMTC program’s safety standards.
