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.
Biochemical assessments reveal increased oxidative stress, inflammation, and modulated gene expression linked to lipid metabolism and angiogenesis. In several experiments, higher doses (for instance, exposures equivalent to levels producing dose-dependent effects in mice) correspond with more pronounced adverse outcomes. These findings indicate that microplastic exposure during gestation may perturb maternal, placental, and fetal systems in measurable ways.
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 (detected in placenta) | Human |
| Barrozo et al., 2024 | Observational | Polyethylene, < 20 μm | Not applicable (detected in placenta) | Human |
| Cary et al., 2024 | Animal experimental | Polystyrene nanoplastic | Intratracheal instillation | Rats |
| Chen et al., 2022 | Animal experimental | Polystyrene, 100 nm | Drinking water | Mice |
Based on the information extracted from the included studies, we observed the following patterns:
- Study Design:
- Animal experimental: 33 studies
- Observational: 6 studies
- In vitro: 2 studies
- Systematic review: 1 study
- Microplastic Type:
- Polystyrene: 28 studies
- Polyethylene: 8 studies
- Various or not specified: 4 studies
- Microplastic Size:
- Nanoplastics: 19 studies
- Microplastics: 15 studies
- No size information found: 8 studies
- Exposure Route:
- Drinking water: 5 studies
- Detection in placenta: 5 studies
- Oral gavage: 4 studies
- Intratracheal instillation: 3 studies
- Maternal transfer: 2 studies
- No exposure route information found: 7 studies
- Species/Model:
- Mice: 25 studies
- Rats: 8 studies
- Human: 7 studies
- Other (e.g., chick embryos, cell lines): 2 studies
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, diminished fertility | No mention found | No mention found |
| Fournier et al., 2020 | Organ deposition | Nanopolystyrene particles in lung, heart, spleen | 2.64 × 10^14 particles | No mention found |
The studies reported various maternal effects associated with microplastic exposure during pregnancy, including changes in body weight, reproductive system, metabolism, liver function, and cardiovascular system.
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 |
| Barrozo et al., 2024 | Placenta | Microplastic accumulation | Mean 6.91 mg/g | Microplastics detected in 100% of placentae |
| Dou et al., 2024 | Reproductive (offspring) | Decreased sperm count and viability in male offspring | No mention found | Transgenerational reproductive toxicity |
Multiple studies reported significant effects on fetal growth, neurodevelopment, and placental function. Several studies also detected microplastics in placental tissue and meconium. Additionally, reports of metabolic changes, reproductive effects, and multi-system impacts in offspring exposed to microplastics during development were found.