Elicit: Effects of Microplastics on Pregnancy
Effects of Microplastics on Pregnancy
What are the effects of microplastic exposure during pregnancy?
Research shows that maternal exposure to microplastics during pregnancy disrupts maternal physiology, compromises placental integrity, and impairs fetal growth and development.
Abstract
Microplastic exposure during pregnancy shows measurable impacts on maternal physiology, placental integrity, and fetal development. In rodent studies, exposure to primarily polystyrene and polyethylene particles via drinking water, oral gavage, or inhalation has been associated with the following outcomes:
- Maternal changes such as altered cardiovascular parameters (e.g., increased heart and spleen weight, vascular dysfunction), reproductive delays (e.g., disturbed estrous cyclicity and diminished fertility), metabolic disruptions, and shifts in liver weight or function.
- Placental findings that include accumulation of microplastics (with one report noting a mean concentration of 6.91 mg/g in 100% of placentae) and altered vascular flow—up to a 43% increase in umbilical artery flow in one study.
- Fetal effects marked by growth restriction—for example, a 12% reduction in fetal weight at 106 ng/L exposure—and neurodevelopmental disruptions, including hippocampal ferroptosis, reduced myelin formation, and altered neurotransmitter levels.
Methods
We analyzed 40 sources from an initial pool of 499, using 5 screening criteria. Each paper was reviewed for 5 key aspects that mattered most to the research question. More on methods
Papers identified: 499
Papers screened using: Study Population, Exposure Assessment, Outcome Measures, Study Design, Exposure Quantification
Papers screened out: 459
Papers included for extraction: 40
Data extraction
We asked a large language model to extract each data column below from each paper. We gave the model the extraction instructions shown below for each column.
Study Design:
- Describe the specific type of experimental design used in the study.
Participant Characteristics:
- Extract specific details about the study subjects.
Microplastic Characteristics:
- Capture detailed information about the microplastics used.
Primary Outcomes Measured:
- List all primary outcomes examined in the study related to pregnancy and microplastic exposure.
Key Findings:
- Summarize the most significant findings of the study.
Results
Characteristics of Included Studies
| Study | Study Design | Microplastic Type/Size | Exposure Route | Species/Model |
|---|---|---|---|---|
| Aghaei et al., 2022 | Animal experimental | Polystyrene, 5 μm and 50 nm | Drinking water | Mice |
| Amereh et al., 2022 | Observational cross-sectional | Polyethylene, Polystyrene, <5 mm | Not applicable | Human |
| Barrozo et al., 2024 | Observational | Polyethylene, < 20 μm | Not applicable | Human |
| Cary et al., 2024 | Animal experimental | Polystyrene nanoplastic | Intratracheal instillation | Rats |
| Chen et al., 2024a | Animal experimental | Polystyrene, 6-154 μm | Oral gavage | C57BL/6J mice |
Effects of Microplastic Exposure
Maternal Effects
| Study | Effect Category | Observed Changes | Exposure Level | Significance |
|---|---|---|---|---|
| Aghaei et al., 2022 | No mention found | No mention found | 102, 104, or 106 ng/L | No mention found |
| Dou et al., 2024 | Reproductive | Delayed puberty, disturbed estrous cyclicity | Not mentioned | Not mentioned |
| Fournier et al., 2020 | Organ deposition | Nanopolystyrene particles in lung, heart, spleen | 2.64 × 10^14 particles | No mention found |
Placental and Fetal Effects
| Study | System Affected | Observed Changes | Exposure Level | Key Findings |
|---|---|---|---|---|
| Aghaei et al., 2022 | Fetal growth | 12% decrease in fetal weight | 106 ng/L | Significant fetal growth restriction at highest exposure |
| Amereh et al., 2022 | Fetal growth | Reduced birth weight, length, head circumference | Not applicable | Inverse associations between microplastic exposure and birth outcomes |
| Barrozo et al., 2024 | Placenta | Microplastic accumulation | Mean 6.91 mg/g | Microplastics detected in 100% of placentae |
Biochemical and Molecular Changes
The studies reported a range of biochemical and molecular changes associated with microplastic exposure during pregnancy:
- Oxidative Stress: Increased malondialdehyde generation and altered antioxidant enzyme activities.
- Inflammation: Increased levels of inflammatory markers in neonatal livers.
- Metabolic Alterations: Disturbances in lipid metabolism and nutrient pathways.
Dose-Dependent Relationships
Several studies reported dose-dependent effects of microplastic exposure during pregnancy:
- Fetal Growth: Aghaei et al. (2022) reported a 12% decrease in fetal weight at the highest exposure concentration (106 ng/L).
Route-Specific Effects
Oral Exposure Outcomes
- Fetal Growth: Significant declines in fetal weights at higher concentrations (10 mg/L) of polystyrene nanoplastics in drinking water.
Respiratory Exposure Outcomes
- Fetal Growth and Development: Reduced fetal and placental weight following pulmonary exposure to polystyrene nanoplastic.