The C8 Health Study tracked 69,000 people exposed to PFOA contamination in West Virginia and Ohio. A scientific panel concluded there's a 'probable link' between PFOA exposure and pregnancy-induced hypertension, including preeclampsia. A 2023 meta-analysis of 15 studies in Environmental Research linked higher PFOA and PFOS exposure to higher preeclampsia risk (pooled relative risks of 1.39 and 1.51). Preeclampsia affects an estimated 5-8% of US pregnancies and is a leading cause of maternal illness and death. Reverse osmosis filtration removes PFAS from drinking water.
Starting in 1951 and continuing for decades, DuPont's Washington Works plant in Parkersburg, West Virginia released PFOA (perfluorooctanoic acid, also called C8) into the Ohio River and surrounding environment. The resulting contamination reached six public water districts in the mid-Ohio Valley.
In 2005, as part of a class-action settlement, DuPont funded the C8 Health Project – an independent health study of everyone who had lived or worked in the contaminated area for at least one year between 1950 and 2004. Nearly 69,000 people enrolled. The C8 Science Panel, a group of epidemiologists tasked with evaluating the health impacts, examined blood PFOA levels and medical records for over a decade.
Their conclusion on pregnancy outcomes, issued in December 2011: a probable link between PFOA exposure and pregnancy-induced hypertension. That includes preeclampsia – the more severe form that involves protein in the urine and organ damage.
This wasn't a small pilot study or animal research. This was 69,000 real people with measured blood levels and documented medical histories. The Science Panel's findings on preeclampsia remain the strongest human evidence linking PFAS to a pregnancy complication.
Preeclampsia is high blood pressure that develops after 20 weeks of pregnancy, usually accompanied by protein leaking into the urine (proteinuria). It affects an estimated 5-8% of pregnancies in the United States. When severe, it can damage the liver, kidneys, and brain. It can cause seizures (eclampsia), placental abruption, and preterm birth.
According to the CDC, hypertensive disorders of pregnancy, including preeclampsia and eclampsia, caused about 6% of US pregnancy-related deaths in 2011-2015. It's also a leading cause of preterm delivery – babies born before 37 weeks because the only cure for preeclampsia is delivery.
The root cause of preeclampsia isn't fully understood, but the leading hypothesis involves the placenta. In a healthy pregnancy, the placenta releases balanced levels of pro-angiogenic and anti-angiogenic factors – proteins that regulate blood vessel growth. In preeclampsia, that balance tips. The placenta releases too much of an anti-angiogenic protein called sFlt-1 (soluble fms-like tyrosine kinase-1) and not enough of a pro-angiogenic protein called PlGF (placental growth factor). This imbalance disrupts blood vessel formation in the placenta and maternal organs, leading to high blood pressure and organ damage.
PFAS, it turns out, may interfere with this delicate balance. That's the biological mechanism researchers are investigating.
Laboratory research suggests PFAS can alter how the placenta produces angiogenic factors. A 2024 review in Reproductive Toxicology by University of Wisconsin-Madison researchers summarized evidence that PFOS (perfluorooctane sulfonate) lowers expression of the PlGF gene in placental cells, which would push in the direction of the imbalance seen in preeclampsia.
Human biomarker evidence is thinner and mixed. The same review notes a case-control study that found associations between one PFAS (MeFOSAA) and sFlt-1 and the sFlt-1/PlGF ratio, but in the opposite (inverse) direction from what a simple preeclampsia mechanism would predict.
This line of research matters because it offers a plausible biological pathway, but it is not yet proof that PFAS causes preeclampsia through this route.
In 2023, Hu and colleagues published a systematic review and meta-analysis in Environmental Research examining PFAS exposure and hypertensive disorders of pregnancy. They pooled 15 observational studies published before December 2022.
Their findings: higher PFOA exposure was associated with increased preeclampsia risk (pooled relative risk 1.39 across 6 studies, rated low certainty). For PFOS, the association was stronger (relative risk 1.51 across 6 studies, rated moderate certainty).
In other words, women with more PFOA and PFOS in their blood tended to have higher preeclampsia risk, though the certainty ratings show the evidence is still developing.
Gestational hypertension (high blood pressure without proteinuria) is a milder condition than preeclampsia but still risky, and individual cohorts such as Project Viva have also linked PFOA and PFOS to it.
One caveat: not all studies showed the same magnitude of effect. Some found stronger associations, others weaker. Geographic differences in PFAS mixtures (people are exposed to multiple PFAS compounds, not just PFOA and PFOS) may explain some of this variation. But the overall pattern is consistent: higher PFAS, higher risk.
The CDC's National Health and Nutrition Examination Survey (NHANES) tracks PFAS levels in the US population. According to NHANES data from 2017-2018, the geometric mean blood level in the US population is about 1.42 ng/mL (nanograms per milliliter) for PFOA and 4.25 ng/mL for PFOS.
Those are population-wide averages, not pregnancy-specific figures, and individual levels vary widely with water source, diet, and occupation.
In the C8 study, participants had much higher exposures. Median blood PFOA levels in the contaminated area were around 28 ng/mL, roughly 20 times the 2017-2018 US average. This matters because the C8 findings represent a high-exposure scenario. We can't assume that the same magnitude of risk applies at the lower exposures most pregnant women experience today.
But here's the thing: PFAS accumulate in the body over years. They don't break down. Pregnancy doesn't reset your PFAS levels – if anything, PFAS cross the placenta and transfer to the fetus, and studies routinely detect them in umbilical cord blood. Your baby gets exposed to whatever you've accumulated.
Filtering your drinking water lowers PFAS exposure. Reverse osmosis (RO) systems remove 90-99% of PFAS, according to testing by Duke University and the EPA. Activated carbon filters vary widely – some remove 70-80% of long-chain PFAS like PFOA and PFOS, but perform poorly on short-chain PFAS like PFBS and GenX.
If you're pregnant or planning to be, an RO system is the most reliable option. Check our water filter comparison guide for specifics.
You can also reduce PFAS exposure through food. Grease-resistant food packaging (microwave popcorn bags, fast food wrappers, pizza boxes) often contains PFAS. A 2017 analysis of US fast-food packaging in Environmental Science & Technology Letters detected fluorine, a marker of PFAS, in about 46% of food-contact papers. Cooking at home in stainless steel or cast iron avoids this.
Nonstick cookware is another source – older Teflon pans used PFOA in manufacturing (though US manufacturers phased it out by 2015 under a voluntary EPA program). Some newer nonstick coatings use other PFAS. If you're avoiding PFAS, skip the nonstick.
Contaminated drinking water can be the biggest source in affected communities. Environmental Working Group scientists estimated in 2020 that more than 200 million Americans could have PFAS in their tap water at 1 ppt or higher. Check your water quality by zip code to see if your local utility has tested for PFAS. Not every system has been tested: the EPA's UCMR5 program (2023-2025) required testing for 29 PFAS at systems serving 3,300 or more people, plus a sample of smaller systems.
Commercial PFAS blood tests exist, but most OB-GYNs don't recommend them for routine prenatal care. Here's why: knowing your blood PFAS level doesn't change your clinical management. There's no medical intervention that lowers PFAS once it's in your bloodstream. The half-life of PFOA in humans is 2-4 years. PFOS is similar or longer, roughly 3-5 years. You can't detox PFAS.
What you can do is reduce ongoing exposure. Filtering water, avoiding grease-proof packaging, and monitoring blood pressure starting at 20 weeks are all practical steps. Your OB will screen for preeclampsia at every visit through blood pressure checks and urine protein tests.
If you live in a known PFAS contamination zone (near a military base, chemical plant, or airport – these are the most common sources), testing might make sense for documentation purposes. Some states allow PFAS blood testing through public health programs. But from a clinical standpoint, it won't change what your doctor does.
What does change clinical management: screening your blood pressure carefully and frequently. If you have a family history of preeclampsia, hypertension, or kidney disease, you're already at higher risk. PFAS exposure may compound that risk. Starting at 20 weeks, check your blood pressure at every OB visit. Home monitoring is also reasonable – the American College of Obstetricians and Gynecologists (ACOG) supports home blood pressure monitoring for pregnant women at risk of hypertensive disorders.
We know less about newer PFAS. PFOA and PFOS have been studied for decades because they were produced in massive quantities and accumulate in blood. GenX, PFBS, and other replacement PFAS are shorter-chain compounds that clear the body faster – but they're also less studied. Early animal research suggests some of these replacements may have similar endocrine-disrupting effects, but human pregnancy data is sparse.
The PFAS mixtures question is also unsolved. People aren't exposed to just one PFAS – we're exposed to dozens simultaneously. Do they have additive effects? Synergistic effects? The meta-analyses typically look at individual PFAS compounds, but that's not how real-world exposure works. Mixture methods are newer and results so far are limited. More research is needed here.
Another gap: timing of exposure. Does PFAS exposure before pregnancy matter as much as exposure during pregnancy? Does exposure in the first trimester matter more than the third? Most studies measure PFAS at one point during pregnancy (often mid-pregnancy) and correlate that with outcomes. Longitudinal studies tracking PFAS levels throughout pregnancy and even preconception are rare but would tell us more about critical windows.
Preeclampsia is a serious complication. PFAS exposure appears to increase the risk, based on the best available evidence from the C8 study, the 2023 meta-analysis, and early mechanistic research on placental angiogenesis.
The magnitude of risk is modest. Preeclampsia already affects an estimated 5-8% of pregnancies, so a relative increase in the range the meta-analysis reported is a small absolute change for any one person. But across millions of pregnancies, it adds up.
If you're planning to get pregnant or are currently pregnant, reducing PFAS exposure is a reasonable precaution. Filter your drinking water. Avoid grease-resistant food packaging. Monitor your blood pressure starting at 20 weeks. These steps won't eliminate preeclampsia risk – most cases aren't caused by PFAS – but they reduce one modifiable risk factor.
We've built a pregnancy PFAS exposure guide that covers infant formula contamination, water safety, and what to ask your OB. For those trying to conceive, our preconception PFAS guide discusses ways to lower exposure before pregnancy. And if you're concerned about PFAS in your area, check your local water quality – we pull EPA testing data for your zip code.
This article is for general information and is not medical advice; talk with your OB-GYN about your own risk. It contains affiliate links – if you buy through them, we may earn a small commission at no extra cost to you.
The PFAS-preeclampsia link has real support. The C8 probable link determination, the pooled associations in the 2023 meta-analysis, and early lab evidence on placental angiogenic factors (PlGF) all point in the same direction, even though the certainty of the evidence is still rated low to moderate.
Is PFAS the cause of most preeclampsia cases? No. Preeclampsia is multifactorial – genetics, obesity, chronic hypertension, diabetes, and autoimmune conditions all play roles. PFAS is one piece of a larger puzzle.
But it's a piece we can do something about. Unlike your family history or pre-existing health conditions, PFAS exposure is modifiable. You can filter your water, change your cookware, and avoid contaminated food packaging. You can't eliminate PFAS entirely – it's already in your blood and everyone else's – but you can stop adding to it.
For pregnant women in high-exposure areas (military bases, industrial zones, contaminated water districts), reducing PFAS intake should be part of prenatal care conversations. For everyone else, it's a reasonable precaution. The science is strong enough to act on. The risk is real enough to take seriously.
Read more about PFAS in pregnancy or check if your water is contaminated.
Does filtering water lower preeclampsia risk? Filtering PFAS from drinking water reduces your ongoing exposure, which should lower your blood PFAS levels over time – though PFOA and PFOS have half-lives of roughly 2-5 years, so existing levels won't drop quickly. EPA research shows reverse osmosis typically removes more than 90% of PFAS. Since higher PFAS correlates with higher preeclampsia risk, reducing exposure is a reasonable precaution, but no studies have directly tested whether installing a filter lowers preeclampsia rates.
How much PFAS is in pregnant women's blood on average? According to CDC NHANES data from 2017-2018, the geometric mean PFOA level in the US population is about 1.42 ng/mL and the PFOS level is about 4.25 ng/mL. These are population-wide averages – your level depends on where you live, what you eat, and your water source. Women in PFAS-contaminated areas can have levels 10-20 times higher.
Is preeclampsia caused by PFAS? Preeclampsia is multifactorial – genetics, obesity, chronic hypertension, and other factors all contribute. PFAS exposure increases risk but doesn't cause all or even most cases. The C8 Science Panel determined a 'probable link' between PFOA and pregnancy-induced hypertension, and a 2023 meta-analysis found higher preeclampsia risk with higher PFOA and PFOS exposure. PFAS is one modifiable risk factor among many.
Should I get a PFAS blood test if I'm pregnant? Most OB-GYNs don't recommend routine PFAS blood testing because knowing your level doesn't change clinical management – there's no way to quickly remove PFAS once it's in your system. Testing might make sense if you live near known contamination sources and want documentation. The better strategy: reduce ongoing exposure through filtered water and careful food choices, and monitor blood pressure closely starting at 20 weeks.
What PFAS level is dangerous in pregnancy? There's no established threshold or 'safe level' for PFAS in pregnancy. The 2023 meta-analysis found higher preeclampsia risk with higher PFOA and PFOS exposure. The C8 study participants had median PFOA levels around 28 ng/mL (much higher than the 2017-2018 US average of about 1.4 ng/mL) and showed elevated risk. Lower exposures may carry lower risk, but research hasn't identified a no-effect level.