Do Microplastics Affect Pregnancy? What New Research Shows
A new placenta cell-model study and one Rutgers toxicologist's own pregnancy show how far microplastics reach.
Key takeaway: Yes, at least in the lab model built to test it: a 2026 study from Vrije Universiteit Amsterdam found that several types of micro- and nanoplastics crossed a three-layer human placental cell model within 72 hours and altered hormone levels, including estrogen. Real-world harm to a fetus isn't proven yet…
By Dear Sarah · · Updated
Key takeaways
- A 2026 study led by toxicologist Jeske van Boxel at Vrije Universiteit Amsterdam found that four of five tested plastic types crossed a three-layer human placental cell model within 72 hours, with the acrylic PMMA moving fastest.
- The same study found that several plastic types lowered the steroid hormone etiocholanolone, and that polystyrene specifically lowered estrogen output in the model.
- Rutgers toxicologist Sam Adams, who studies microplastic exposure during pregnancy, became pregnant herself in 2025 and changed her own habits, including adding home air filtration and switching to filtered or bottled water.
- Bottled water can contain roughly 250,000 to 400,000 nanoplastic particles per liter, and only about 5% of plastic in the U.S. is actually recycled.
- Global plastic production is on track to nearly triple by 2060, which is part of why researchers say reducing everyday plastic exposure matters well before pregnancy becomes a factor.
If you're pregnant, hoping to be, or just plan to be someday, you've probably had a quiet, uneasy thought about how much plastic ends up in your body. The honest answer: more than any of us would like, and new research says some of it may be crossing further than we thought. A study out of Vrije Universiteit Amsterdam this summer found that several common types of microplastics can cross a lab-built model of the human placenta within three days, and once there, they shift hormone levels. Researchers at Rutgers, separately, have found plastic particles in essentially every human placenta they've tested. None of this is a reason to panic. It's the science finally catching up to something a lot of us already felt in our gut.
Can microplastics really cross the placenta?
Yes, at least in the lab model built to test it. Environmental toxicologist Jeske van Boxel and her team at Vrije Universiteit Amsterdam layered living human cells to mimic the barriers a molecule crosses to get from a pregnant person's bloodstream to a fetus. They exposed it to five common plastic types, including polystyrene, PVC, and PMMA (the acrylic used in a lot of packaging and cosmetics). Over 72 hours, four of the five crossed every layer, smaller particles more easily than larger ones, with PMMA moving fastest. Once across, the plastics didn't pass through quietly: several types lowered a steroid hormone called etiocholanolone, and polystyrene specifically lowered estrogen output. "Our study shows that several types of micro- and nanoplastics can cross a human placental model and influence hormone production," van Boxel said, while noting the model can't yet prove real-world harm to a fetus. Still, it's the clearest evidence yet that the placenta, long assumed to be a strong filter, isn't as sealed off as we thought.
What one researcher learned by living her own study
Sam Adams is a toxicologist and PhD candidate in Dr. Phoebe Stapleton's lab at Rutgers, where she studies how airborne particulate matter, including microplastics, moves through a pregnant body. She found out she was pregnant in the summer of 2025, mid-research, and it changed how she ran her own life: she paused certain lab experiments, added air filtration at home, and switched to bottled water over concerns about her tap water in Newark. Her son Joey was born in April 2026. Stapleton's lab has already shown that inhaled polystyrene nanoplastics cross the placenta in rats, and that pups exposed to high microplastic levels were born smaller; her current work looks at how these particles affect glucose metabolism in pregnancy. "We don't necessarily know what that plastic exposure might lead to yet," Stapleton has said. That kind of honesty, admitting what the science doesn't know yet instead of overselling either fear or reassurance, is worth trusting.
Why this matters if you're a young woman right now
This isn't only a story for people who are pregnant today. It's a story about the water you're drinking, the questions you'll eventually bring to a doctor, and how seriously those questions get taken. Bottled water alone can carry somewhere between 250,000 and 400,000 nanoplastic particles per liter, only about 5% of plastic in the U.S. actually gets recycled, and global plastic production is on track to nearly triple by 2060. That trajectory doesn't reverse on its own, which is part of why how much microplastic one laundry load actually sheds and whether composting food scraps adds microplastics to soil are worth understanding now, long before a pregnancy test ever enters the picture. It also connects to something bigger: research on women's bodies has historically lagged behind research on men's, which is part of why so many young women don't trust the health care system to take their concerns seriously in the first place. Studies like this one are a sign that's starting to shift, even if slowly.
One thing to try today
Pick one plastic-heavy habit and swap it, not all of them at once. If you're drinking bottled water daily, look into a basic filter pitcher or a filtered tap attachment instead. It's a five-minute decision that cuts your exposure to one of the sources researchers keep flagging, and it's the kind of small, doable move that adds up without asking you to overhaul your whole life.
Quote to sit with
"The eyes of the future are looking back at us, and they are praying for us to see beyond our own time." — Terry Tempest Williams, Refuge: An Unnatural History of Family and Place
💌 Sarah
Frequently asked questions
Do microplastics cross the placenta?
In a 2026 lab model built from real human cells, yes: four of five plastic types tested crossed all three simulated barrier layers within 72 hours. Researchers are careful to note the model isn't the same as a real pregnancy, so it shows the pathway is possible, not that it definitely causes harm to a fetus.
Can microplastics affect hormones during pregnancy?
A Vrije Universiteit Amsterdam study found several plastic types lowered a steroid hormone called etiocholanolone, and that polystyrene specifically reduced estrogen output in a placental cell model. Whether that translates to hormone changes in an actual pregnancy is still being studied.
How much plastic is actually found in human placentas?
A widely cited 2024 study found microplastics in all 62 human placentas tested, with placentas from premature births showing higher concentrations than those from full-term births. Rutgers researchers are now studying how those particles might affect glucose metabolism in pregnancy.
Does bottled water contain microplastics?
Yes. Research cited by Rutgers toxicologist Sam Adams found that bottled water can contain roughly 250,000 to 400,000 nanoplastic particles per liter, which is part of why she changed her own household water habits during her pregnancy.
Should I stop using plastic if I'm trying to get pregnant?
No one is telling you to eliminate plastic overnight, and researchers aren't recommending that either. The more useful move is reducing your highest exposure sources, like bottled water or old food storage containers, while scientists keep studying what the exposure actually means long-term.
Sources
- How Do You Figure Out if Microplastics Are Affecting Pregnancy? — Science Friday
- How do you figure out if microplastics are affecting pregnancy? — The 19th
- New Evidence That Microplastics Can Cross Placental Barrier And Alter Hormone Production — ScienceAlert
- Micro- and nanoplastics cross a human placental barrier model and alter steroidogenesis — Molecular and Cellular Endocrinology
Keep reading
- What Is 'Living Plastic' and Could It End Microplastics? — A scientist just built plastic that destroys itself in six days with no microplastics left behind. Here's how, and why it matters more than another straw ban.
- How much microplastic does one laundry load actually shed? — One load of laundry can shed 700,000 microfibers. Six low-lift changes that actually keep them out of the water, starting with your next wash.
- Does Sorting Your Trash Actually Reduce Plastic Pollution? — You've probably wondered if your recycling actually does anything. A new women-led campaign — and the data behind it — says sorting right changes everything.
- Does Composting Food Scraps Add Microplastics to Soil? — New research says composting cuts climate impact up to 99%, but plastic can sneak in too. Here's the fix.