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 Johns Hopkins meta-analysis found a 16% increased odds of preeclampsia per doubling of maternal PFOA levels. Preeclampsia affects 5-8% of US pregnancies and is the second-leading cause of maternal death. Reverse osmosis filtration removes PFAS from drinking water.
Between 1951 and 2003, DuPont's Washington Works plant in Parkersburg, West Virginia dumped PFOA (perfluorooctanoic acid, also called C8) into the Ohio River and surrounding environment. The resulting contamination affected six water districts serving roughly 80,000 people 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, published in 2010 by Frisbee and colleagues in Environmental Health Perspectives: 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 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, preeclampsia and eclampsia are the second-leading cause of maternal death in the US, responsible for roughly 8% of pregnancy-related deaths. 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.
Animal studies and human placental cell research show that PFAS exposure alters the production of angiogenic factors. A 2018 study in Toxicological Sciences found that PFOA and PFOS (perfluorooctane sulfonate) exposure in pregnant mice increased circulating sFlt-1 and decreased PlGF – the exact imbalance seen in preeclampsia.
Human studies back this up. A 2021 paper in Environment International measured PFAS levels in 1,003 pregnant women in China and found that higher PFOA and PFOS concentrations correlated with improved sFlt-1 and reduced PlGF in maternal blood. The women with the highest PFAS levels had a sFlt-1/PlGF ratio consistent with early preeclampsia risk.
This mechanism is important because it gives us a clear biological pathway. PFAS doesn't just correlate with preeclampsia by coincidence – it disrupts the molecular process that prevents preeclampsia in healthy pregnancies.
In 2023, researchers at Johns Hopkins Bloomberg School of Public Health published a systematic review and meta-analysis in Environmental Health Perspectives examining PFAS exposure and hypertensive disorders of pregnancy. They analyzed 16 studies covering over 25,000 pregnancies across the US, Europe, and Asia.
Their findings: for every doubling of maternal PFOA concentration, the odds of developing preeclampsia increased by 16%. For PFOS, the association was weaker but still present – a 12% increase per doubling.
These are dose-response relationships. The more PFAS in a pregnant woman's blood, the higher her risk. This pattern held across different populations, study designs, and geographic regions.
The meta-analysis also found associations between PFAS and gestational hypertension (high blood pressure without proteinuria) – a milder condition than preeclampsia but still risky. PFOA showed a 13% increased odds per doubling for gestational hypertension.
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 the most recent NHANES data (2017-2018), the median PFOA level in women of reproductive age is 1.2 ng/mL (nanograms per milliliter). The median PFOS level is 3.7 ng/mL.
Those are medians – half of women have more, half have less. The 95th percentile (the top 5% of exposures) sits around 4.5 ng/mL for PFOA and 13 ng/mL for PFOS.
In the C8 study, participants had much higher exposures. Median blood PFOA levels in the contaminated area were around 28 ng/mL – more than 20 times the current US median. 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. A 2024 study in Environmental Science & Technology Letters found that cord blood PFAS levels average 50-80% of maternal levels. 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. We've analyzed dozens of filters – 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 2019 study in Environmental Science & Technology tested takeout containers and found PFAS in about half of them. Cooking at home in stainless steel or cast iron avoids this.
Nonstick cookware is another source – older Teflon pans used PFOA in manufacturing (though it was phased out in the US by 2013). Some newer nonstick coatings use other PFAS. If you're avoiding PFAS, skip the nonstick.
Contaminated drinking water is still the biggest source for most people. According to the Environmental Working Group, PFAS contamination has been detected in public water systems serving over 200 million Americans. Check your water quality by zip code to see if your local utility has tested for PFAS. Not all systems test for all compounds – the EPA's UCMR5 program (2023-2025) required testing for 29 PFAS, but enforcement is inconsistent.
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 even longer – 5-8 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. A 2022 study in Environmental Research tried to model mixture effects and found that total PFAS burden (summing all detected compounds) predicted preeclampsia risk better than any single PFAS. 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 Hopkins meta-analysis, and mechanistic research on placental angiogenesis.
The magnitude of risk is modest – a 16% increase per doubling of PFOA sounds small. But consider that preeclampsia already affects 5-8% of pregnancies. A 16% relative increase translates to moving from, say, a 6% baseline risk to about 7% at doubled PFOA levels. That's not huge for an individual, 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 was medically reviewed by OB-GYN advisors. 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 is no longer speculative. The C8 probable link determination, the dose-response relationships in the 2023 meta-analysis, and the biological mechanism (sFlt-1/PlGF disruption) all point in the same direction.
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 PFAS has a half-life of 2-8 years, so existing levels won't drop quickly. Studies show reverse osmosis removes 90-99% 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 median PFOA level in women of reproductive age is 1.2 ng/mL and the median PFOS level is 3.7 ng/mL. These are population-wide medians – 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 16% increased odds per doubling of PFOA. 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 risk increases with dose – every doubling of PFOA increased preeclampsia odds by 16%. The C8 study participants had median PFOA levels around 28 ng/mL (much higher than the current US median of 1.2 ng/mL) and showed improved risk. Lower exposures may carry lower risk, but research hasn't identified a no-effect level.