Tiny plastic particles have been discovered in human ovaries for the first time, raising urgent questions about their potential impact on women’s reproductive health. These particles, known as microplastics, along with their even smaller counterparts called nanoplastics, are believed to enter the human body through ingestion, inhalation, and skin contact.
The study that made this discovery examined ovarian follicular fluid – the nourishing liquid surrounding a woman’s eggs – from women undergoing assisted reproductive treatments. Of 18 fluid samples analyzed, 14 contained microplastics, each smaller than 10 micrometres, roughly the width of a strand of hair divided into 10 pieces.
While prior research has shown that microplastics can disrupt reproductive systems in animals, this marks the first time their presence has been confirmed in the human ovarian environment. Researchers suspect the particles enter the ovaries via the circulatory system, eventually embedding in the granulosa cells, which are responsible for producing key reproductive hormones like estrogen and progesterone.
Animal studies have previously shown that microplastics can accumulate in ovarian tissues and disrupt the growth of follicles – the tiny sacs in which eggs mature. These disruptions can also disturb hormonal balances and negatively impact fertility. The presence of microplastics in human follicular fluid suggests a similar mechanism could be at work in people, potentially interfering with egg development, thinning the protective wall around eggs, and increasing the likelihood of ovarian cysts.
Over time, these disturbances could contribute to more serious reproductive health problems. Scientists warn that exposure to microplastics could lead to conditions such as premature puberty, irregular menstrual cycles, premature ovarian insufficiency, endometriosis, fibroids, and even miscarriage. These effects appear to be dose-dependent, meaning higher exposure could cause more severe and possibly irreversible damage.
The study also highlights a critical gap in knowledge: while the presence of microplastics in the human body is increasingly evident, there is limited understanding of the thresholds at which they begin to cause harm. Understanding these exposure levels is key to developing preventive measures and public health guidelines.
The findings come ahead of a major international summit focused on establishing a global treaty to address plastic pollution. As evidence mounts linking microplastics to health risks, particularly in vulnerable systems like human reproduction, the need for policy action becomes more urgent.
Microplastics have been found to accumulate in various human tissues, including lungs, blood, and even penile tissue. Daily human exposure is estimated to range from tens of thousands to millions of particles, often through indoor air, drinking water, and plastic-packaged food. However, measuring internal doses remains difficult due to limited research.
Despite being first identified in the environment decades ago, the long-term health implications of microplastics are still being uncovered. Their persistent nature and ability to penetrate deep into human tissues underscore the need for more research and more stringent environmental protections. This recent discovery of microplastics in ovarian fluid serves as a stark reminder of the hidden costs of plastic pollution – not just to the planet, but to human health and fertility.
