From the Guidelines
Pregnant women should avoid exposure to toxins such as mercury, lead, and organophosphate pesticides, as these have been shown to cause complications during pregnancy, including developmental delays, reduced birth weight, and premature birth. The evidence suggests that mercury, particularly from consuming large predatory fish like shark, swordfish, king mackerel, and tilefish, can damage the developing nervous system 1. Additionally, lead exposure, which can come from old paint, certain water pipes, or some occupational settings, may cause developmental delays, reduced birth weight, and premature birth 1. Organophosphate pesticides have also been linked to poorer cognitive, behavioral, and social development in children, with prenatal exposures associated with increased risks of attention-deficit/hyperactivity disorder and autism spectrum disorder 1. Some medications, such as retinoids and arsenic derivatives, are also highly teratogenic and should be avoided during pregnancy, especially in the first trimester 1. To minimize exposure to these substances, pregnant women should:
- Limit fish consumption to 8-12 ounces per week of low-mercury options
- Avoid handling chemicals and choose fresh foods over processed ones
- Use glass containers instead of plastic and ensure adequate ventilation when using household cleaners
- Avoid exposure to lead and organophosphate pesticides by taking precautions such as wearing protective clothing and masks when working with these substances. These recommendations are based on extensive research showing that these substances can cross the placental barrier and interfere with critical developmental processes during pregnancy.
From the Research
Toxins Associated with Pregnancy Complications
The following toxins have been linked to complications during pregnancy:
- Mercury: exposure to mercury has been associated with pregnancy complications and developmental problems in infants 2
- Heavy metals: preconception exposure to heavy metals can adversely affect fertility, pregnancy, and fetal development 3
- Endocrine-disrupting chemicals: exposure to these chemicals has been linked to reproductive and obstetrical health effects 3
- Pesticides: prenatal exposure to pesticides has been associated with adverse reproductive and obstetrical outcomes 3, 4
- Air pollution: exposure to air pollution during pregnancy has been linked to pregnancy-induced hypertensive disorders and other maternal health outcomes 5
- Lead: exposure to lead increases the risk of pregnancy-induced hypertensive disorders 5
- Flame retardants and plasticizers: these chemicals have been detected in pregnant women and may pose health risks, although the evidence is limited 5
- Disinfectant byproducts and organic solvents: exposure to these chemicals has been linked to adverse pregnancy outcomes, including birth defects and miscarriage 4
Sources of Toxin Exposure
Pregnant women may be exposed to these toxins through various sources, including: