NYU Langone Study Links Glyphosate Exposure During Mid-Pregnancy to Increased Preterm Birth Risk
Key Insights
A new NYU Langone (search) study found that women with glyphosate detected in urine at 18–25 weeks of pregnancy were 37% more likely to have a preterm birth (search) and twice as likely to have a spontaneous preterm birth.
Glyphosate exposure early in pregnancy (before 18 weeks) showed no association with preterm birth (search), and the breakdown product AMPA also showed no link, suggesting unprocessed glyphosate may be the specific concern.
Researchers theorize the herbicide may act through endocrine disruption, oxidative stress, or inflammation, and call for stronger regulations to protect pregnant women and infants.
A new study from NYU Langone (search) has identified a significant association between mid-pregnancy glyphosate exposure and preterm birth (search), adding a troubling dimension to the already contentious debate over the world's most widely used herbicide.
The research, which measured glyphosate levels in the urine of expectant mothers, found that women with detectable glyphosate at 18–25 weeks of pregnancy were 37% more likely to deliver their babies at least three weeks early. More strikingly, these women were two times more likely to experience a spontaneous preterm birth (search) — an unintentional, unplanned early delivery whose cause is often unknown but may involve infection or inflammation.
Timing Matters: Mid-Pregnancy Exposure as a Critical Window
The study revealed a nuanced temporal pattern. When glyphosate was detected in maternal urine early in pregnancy — before 18 weeks — no association with preterm birth (search) was observed. Researchers also measured AMPA, the compound produced when soil microbes break down glyphosate, and found no link between AMPA levels at either early or mid-pregnancy and preterm birth. This suggests that unprocessed glyphosate, rather than its environmental degradation product, may be the specific agent of concern.
“Our findings add to a growing body of evidence that exposure to glyphosate early in life may lead to health concerns that can echo throughout a lifetime,” said study lead author Teresa Herrera, MPH, a doctoral candidate in the Department of Population Health at NYU Grossman School of Medicine.
Mechanisms Under Investigation
While the precise biological mechanism remains unclear, the research team theorizes that glyphosate could be contributing to preterm birth (search) through endocrine disruption, oxidative stress, or inflammation. Preterm birth remains a leading cause of illness and death in children under five, with affected infants often requiring neonatal intensive care and facing potential long-term challenges in physical development and learning.
“These results underscore the need for stronger regulations to protect the health of pregnant women and infants, two groups long known to be especially vulnerable to chemicals in the environment,” added study senior author Leonardo Trasande, MD, MPP, the Jim G. Hendrick, MD, Professor of Pediatrics at NYU Grossman School of Medicine.
A Chemical Under Scrutiny
Glyphosate, the active ingredient in Bayer (search)'s Roundup herbicide, is sprayed on approximately 300 million acres of American farmland annually. The chemical is pervasive: over 80% of people in the United States over the age of 6 have detectable glyphosate in their systems, with exposure occurring through water, crops, and food products including olive oil, honey, fruits, nuts, and cereal.
The World Health Organization's International Agency for Research on Cancer has classified glyphosate as a probable carcinogen. Bayer (search) has proposed a $7.25 billion settlement for tens of thousands of lawsuits linking the chemical to non-Hodgkin lymphoma (search). However, on June 25, the U.S. Supreme Court ruled in a 7-2 decision that Bayer is shielded from state-level failure-to-warn lawsuits, as federal regulations do not require such cancer risk warnings.
Regulatory and Political Crosscurrents
The study emerges amid a complex regulatory landscape. In February, President Trump issued an executive order ramping up production of phosphorus and glyphosate, citing their importance to defense and food security. The administration's MAHA (Make America Healthy Again) strategy has drawn criticism from activists who argue that its regenerative agriculture initiatives fail to address glyphosate's harms.
“The Administration is trying to have it both ways,” said Scott Faber, SVP of Government Affairs for the Environmental Working Group (search). “The May 2025 MAHA assessment described an environmental hellscape in which our children were being poisoned by a toxic mixture of pesticides. But in practice, the second Trump administration had either granted or sought legal immunity for pesticide companies.”
The EPA, for its part, maintains that glyphosate “remains one of the most relied-upon and widely used tools in American agriculture” and that every pesticide registration undergoes “one of the most rigorous, transparent, science-based reviews in the world.” The agency has announced a comprehensive scientific review of glyphosate, including evaluation of independent peer-reviewed research on potential cancer and developmental risks.
The NYU Langone (search) findings add urgency to calls for regulatory reassessment, particularly regarding vulnerable populations. As Herrera and Trasande's research demonstrates, the consequences of glyphosate exposure may begin before birth.