Fertility
Toxins and climate harms having ‘alarming’ effect on fertility, research warns
Simultaneous exposure to toxic chemicals and climate-related heat may be worsening fertility harms across humans and wildlife, research suggests.
The review of scientific literature looks at how endocrine-disrupting chemicals, often found in plastic, together with climate-related effects such as heat stress, are each linked to lower fertility and fecundity, meaning the ability to reproduce, across species including humans, wildlife and invertebrates.
Though the reproductive harms of each issue in isolation are well studied, there is little research on what happens when living organisms are exposed to both.
“Together, the two issues are likely to pose a greater threat to fertility, and the additive effect is “alarming”, said Susanne Brander, a study lead author and courtesy faculty at Oregon State University.
“You’re not just getting exposed to one, but two, stressors at the same time that both may affect your fertility, and in turn the overall impact is going to be a bit worse,” Brander said.
The paper looked at 177 studies.
Shanna Swan, a co-author on the new paper, co-produced a 2017 study that found sperm levels among men in western countries had fallen by more than 50 per cent over four decades. Other research has suggested human fertility has been declining at a similar rate.
The University of Washington’s Institute for Health Metrics and Evaluation has previously said the world was approaching a “low-fertility future”, with more than three quarters of countries below replacement rate by 2050.
The new paper’s authors focused on the effects of endocrine-disrupting chemicals and substances, including microplastics, bisphenol, phthalates and PFAS.
These are thought to cause a range of serious reproductive problems, disrupt hormones and be a potential driver of falling fertility.
Brander said the harms linked to these chemicals are often similar across organisms, from invertebrates to humans.
Phthalates, for example, have been linked to altered sperm shape in invertebrates, spermatogenesis in rodents, meaning sperm production, and reduced sperm counts in humans.
PFAS are also thought to affect sperm quality, and both have been linked to hormone disruption.
The chemicals are widespread in consumer goods, so people are often regularly exposed.
Meanwhile, previous research has shown how rising temperatures, lower oxygen levels and heat stress, among other effects linked to climate change, may also worsen infertility.
Heat stress has been found to affect human hormones, and is linked to spermatogenesis in rodents and bulls.
Research shows temperature also plays a role in sex determination in fish, reptiles and amphibians.
The species has evolved to choose which sex it produces in part based on temperature, and the heating planet can “push it too far in one direction or the other, which overrides that evolutionary benefit”, Brander said.
Similarly, many endocrine disruptors may alter environmental sex determination.
The study set out some of the overlapping effects of chemical exposure and climate change across taxonomic groups, from invertebrates to humans.
In birds, for example, exposure to increased temperature, PFAS, organochlorines and pyrethroids may each individually cause abnormal sperm, increased fledgling mortality, abnormal testes and population decline.
“What happens if they’re exposed to more than one of those stressors at the same time? There has been little exploration of that question.
“Even if there have not been a lot of studies looking at these simultaneously, if you have two different factors that both cause the same adverse effect, then there’s a likelihood that they are going to be additive,” Brander said.
Katie Pelch, a senior scientist with the Natural Resources Defense Council nonprofit, who was not part of the study, said the authors had reviewed high-quality science.
She said she wanted to see more examples of the overlap in impacts, but agreed with the overall premise.
“It is likely [multiple stressors] would have an additive effect, at very least, even if they have different mechanisms of harm,” Pelch added.
The solution to the systemic problems would involve tackling climate change and reducing the use of toxic chemicals.
The study cites the global reduction in the use of DDT and PCBs achieved under the Stockholm Convention as an example of an effective measure, but Brander said much more is needed.
“There is enough evidence in both areas to act to reduce our impact on the planet,” she said.
AI could transform ovarian care by personalising cancer and fertility treatment, but more clinical validation is needed before routine use.
A systematic review and meta-analysis found AI models showed high diagnostic accuracy for ovarian cancer when combining data such as ultrasound scans and blood test results.
Across 81 studies, AI models correctly identified ovarian cancer in around nine out of 10 cases, with pooled rates of 89 to 94 per cent.
They were also highly accurate at ruling out ovarian cancer when it was not present, with specificity of 85 to 91 per cent.
The analysis also found that explainable AI tools could predict complete surgical cytoreduction in advanced ovarian cancer.
Complete surgical cytoreduction means removing all visible cancer during surgery, which can be an important goal in treatment planning.
The tools achieved a pooled AUC of 0.87. AUC is a measure of how well a model distinguishes between different outcomes, with higher scores showing stronger performance.
In reproductive medicine, AI algorithms helped physicians optimise ovarian stimulation protocols and predict follicular growth during IVF.
Ovarian stimulation is the use of hormones to encourage the ovaries to produce eggs, while follicles are the small sacs in the ovaries where eggs develop.
The review found AI could reliably model ovarian response in IVF with a pooled AUC of 0.81.
However, researchers said challenges remain in translating promising research findings into routine clinical practice.
They identified substantial variation across studies, driven by retrospective study designs, variable AI systems and a lack of standardised validation.
Only 22 per cent of analysed studies reported prospective, multicentre external validation, where models are tested forward in time across multiple healthcare settings.
The authors called for rigorous validation to help close the gap between research and routine clinical practice, alongside standardised methodological and reporting frameworks, smooth integration with clinical workflow and robust governance to support responsible and ethical AI use.
They concluded: “Artificial intelligence is a transformative force in the management of ovarian conditions.
“In gynaecologic oncology, AI enhances every phase of care, from early detection and accurate diagnosis to prognostic stratification and surgical planning.”
In reproductive medicine, AI personalises ovarian stimulation and refines the diagnosis of heterogenous endocrine disorders such as PCOS.
PCOS, or polycystic ovary syndrome, is a hormonal condition that can affect periods, skin, weight and fertility.
Housing, work and fertility pressures are stopping many Britons growing the families they want, new research suggests.
A UK fertility report found that 79 per cent of people surveyed who had tried to conceive in the past five years would like more children than they currently have.
Among parents with one child, that figure rises to 88 per cent.
The report surveyed more than 1,000 people across the UK who had tried for a baby in the past five years.
While birth rates continue to fall, the findings suggest it is not because people no longer want children. Instead, many respondents said external pressures are making it harder to grow their families.
The findings, from wellness brand Wild Nutrition’s Fertility Disconnect report, highlight how financial pressures, fertility struggles and gaps in reproductive health knowledge are shaping modern family life in the UK.
Gail Madalena, fertility nutritional therapist at Wild Nutrition, said: “People often assume fertility begins the moment they decide to try [for a baby].
“In reality, egg and sperm health are shaped months and years earlier.
“By the time someone starts thinking about fertility, their body has already been responding to its environment for a long time.”
Among the biggest barriers, 26 per cent said career progression affected their family plans, 25 per cent cited housing affordability and lack of space, and 52 per cent said they required medical intervention during their fertility journey.
The report also found that almost a quarter of respondents had spent more than two years trying to conceive.
Trying for a baby can take a significant toll on mental health and relationships, especially for those navigating fertility treatment.
According to the research, 38 per cent of respondents said trying to conceive had negatively affected their mental health. That figure rose to 99 per cent among people undergoing fertility treatment.
Julianne Boutaleb is a perinatal psychologist.
She said: “Navigating a fertility journey is about so much more than medical appointments and procedures.
“It’s an emotional marathon that can take a huge toll on your mental wellbeing.
“Sadly, the stats show that 15 per cent of couples going through fertility treatment say their relationship has been irrevocably impaired.”
The report also highlighted the realities of secondary infertility, which affects around one in 20 people, challenging the assumption that having one child means conceiving again will be straightforward.
Researchers found many people felt under-informed about fertility, particularly younger adults.
Ten per cent of Gen Z respondents said they “know nothing” about fertility, while only one in five respondents said they know “a lot” about egg health.
The report also found that 60 per cent of women were unaware of fertility testing options, and one in five Gen Z respondents said they felt uncomfortable discussing fertility, even with their partner.
Around 40 per cent of those surveyed supported fertility education being included in schools, covering topics such as egg health, sperm health and hormonal health.
The report also explored how lifestyle and long-term health may influence fertility outcomes.
Many respondents said they only made changes once they started trying to conceive.
Some 44 per cent improved their diet when trying for a baby, while 32 per cent reduced alcohol intake at that stage.
The report also referenced emerging research that suggests ultra-processed foods and microplastics could have an impact on reproductive health.
While fertility conversations often focus on women, the findings showed male fertility issues are also affecting many families.
Seventeen per cent of respondents cited sperm health issues as a barrier to conception, while male factors contribute to around half of all fertility challenges.
Only one in four men said they would share fertility struggles with friends.
“Many causes of male infertility are entirely treatable yet so often the last resort is the first response,” said Ian Stones, co-founder at Test Him Ltd.
The findings come as UK birth rates remain below replacement level.
The report noted that the UK fertility rate is now 1.41, meaning that on average women give birth to 1.41 children over their lifetimes. The replacement rate, or rate that maintains population numbers, is 2.1.
It also said the average age of mothers has risen to 31, while birth rates are falling across most age groups except among over-40s.
“There is no single fertility story, and it is rarely a simple, linear narrative,” said Dr Zeynep Gurtin, lecturer in women’s health at UCL.
Dr Gurtin added that better fertility education, fairer access to treatment and more open conversations around infertility and pregnancy loss are needed.
Femtech World is thrilled to reveal the shortlist for the Fertility Innovation Award.
The award, sponsored by FinDBest IVF, celebrates a pioneering product, service or initiative that is transforming fertility care and support.
FinDBest IVF is a global B2B digital platform created to simplify and accelerate how IVF and ART manufacturers connect with trusted, pre-vetted distributors around the world.
This year’s nominees represent a remarkable breadth of approaches to fertility care: from clinic-floor breakthroughs to at-home hormone intelligence to truly borderless access.
Three companies made the cut, with each tackling a real, persistent barrier in reproductive health.
Congratulations to the shortlist and many thanks to everyone who entered.
Fertility Innovation Award Shortlist
HRC Fertility’s Needle-Free IVF is a pioneering advancement designed to transform one of the most challenging aspects of fertility treatment: daily hormone injections.
Developed by board-certified reproductive endocrinologist Dr Rachel Mandelbaum, this innovative approach reimagines how stimulation medications are delivered during IVF and egg freezing, dramatically improving the patient experience while maintaining the same trusted clinical outcomes.
Inspired by feedback from patients who struggled with the injection process, Dr Mandelbaum adapted an innovative drug-delivery system commonly used in other areas of medicine and applied it to reproductive care
Mira is a hormonal health technology company that provides lab-grade hormone testing and AI-driven insights to help women and couples understand their fertility.
The platform has already supported more than 200,000 couples on their fertility journeys worldwide, helping over 60,000+ users achieve pregnancy.
For some users, pregnancy rates have reached up to 89 per cent within six months, demonstrating how accurate hormone data can significantly improve fertility outcomes.
Founded in 2021 by Marija Skujina, a Certified Fertility Nurse Specialist accredited by the European Society of Human Reproduction and Embryology, with nearly 15 years of clinical experience at one of the world’s top IVF clinics, and having navigated her own fertility journey as a patient, Marija built the clinic she had always wished existed.
Plan Your Baby began with a bold, but simple mission – make best quality fertility and pregnancy available anywhere.
Plan Your Baby has created a new generation fertility and pregnancy clinic with patients accessing expert consultations remotely, while blood tests and ultrasound scans are available at over 450 locations across the UK, eliminating the exhausting travel burden that often forces people to take days off work, relocate appointments, or abandon treatment altogether
What happens now
The shortlist will be judged by a representative from category sponsor FindBestIVF, with the winner announced at a virtual event on June 19.
Winners will receive a trophy and be interviewed by a Femtech World journalist.
Entrepreneur4 weeks agoFuture Fertility raises Series A financing to scale AI tools redefining fertility care worldwide
Entrepreneur3 weeks agoWomen’s digital health market set to reach US$5.28 billion in 2026 – report
Diagnosis4 weeks agoNew meta-analysis further supports low re-excisions and high placement accuracy with the Magseed marker
Pregnancy4 weeks agoNIPT or NT scan? Why the 2026 evidence supports doing Both
News4 weeks agoResistance training has preventative effects in menopause, study finds
Ageing4 weeks agoLifting weights shows mental health and cognitive benefits in older women, study finds
Insight3 weeks agoWhy the UK’s fertility rate keeps falling – and what it means if you’re trying now
Wellness3 weeks agoWomen’s HealthX unveils Northwell Health, Corewell Health, Biogen & more to headline Chronic Disease stage
1 Comment