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A couple tried for 18 years to get pregnant. AI made it happen
A couple tried for 18 years to get pregnant. AI made it happen

CNN

time03-07-2025

  • Health
  • CNN

A couple tried for 18 years to get pregnant. AI made it happen

AI Maternal health Women's health FacebookTweetLink After trying to conceive for 18 years, one couple is now pregnant with their first child thanks to the power of artificial intelligence. The couple had undergone several rounds of in vitro fertilization, or IVF, visiting fertility centers around the world in the hopes of having a baby. The IVF process involves removing a woman's egg and combining it with sperm in a laboratory to create an embryo, which is then implanted in the womb. But for this couple, the IVF attempts were unsuccessful due to azoospermia, a rare condition in which no measurable sperm are present in the male partner's semen, which can lead to male infertility. A typical semen sample contains hundreds of millions of sperm, but men with azoospermia have such low counts that no sperm cells can be found, even after hours of meticulous searching under a microscope. So the couple, who wish to remain anonymous to protect their privacy, went to the Columbia University Fertility Center to try a novel approach. It's called the STAR method, and it uses AI to help identify and recover hidden sperm in men who once thought they had no sperm at all. All the husband had to do was leave a semen sample with the medical team. 'We kept our hopes to a minimum after so many disappointments,' the wife said in an emailed statement. Researchers at the fertility center analyzed the semen sample with the AI system. Three hidden sperm were found, recovered and used to fertilize the wife's eggs via IVF, and she became the first successful pregnancy enabled by the STAR method. The baby is due in December. 'It took me two days to believe I was actually pregnant,' she said. 'I still wake up in the morning and can't believe if this is true or not. I still don't believe I am pregnant until I see the scans.' Artificial intelligence has advanced the field of fertility care in the United States: More medical facilities are using AI to help assess egg quality or screen for healthy embryos when patients are undergoing IVF. There's still more research and testing needed, but AI may now be making advancements in male infertility, in particular. Dr. Zev Williams, director of the Columbia University Fertility Center, and his colleagues spent five years developing the STAR method to help detect and recover sperm in semen samples from people who had azoospermia. They were struck by the system's results. 'A patient provided a sample, and highly skilled technicians looked for two days through that sample to try to find sperm. They didn't find any. We brought it to the AI-based STAR System. In one hour, it found 44 sperm. So right then, we realized, 'Wow, this is really a game-changer. This is going to make such a big difference for patients,' ' said Williams, who led the research team. When a semen sample is placed on a specially designed chip under a microscope, the STAR system – which stands for Sperm Tracking and Recovery – connects to the microscope through a high-speed camera and high-powered imaging technology to scan the sample, taking more than 8 million images in under an hour to find what it has been trained to identify as a sperm cell. The system instantly isolates that sperm cell into a tiny droplet of media, allowing embryologists to recover cells that they may never have been able to find or identify with their own eyes. 'It's like searching for a needle scattered across a thousand haystacks, completing the search in under an hour and doing it so gently, without any harmful lasers or stains, that the sperm can still be used to fertilize an egg,' Williams said. 'What's remarkable is that instead of the usual [200 million] to 300 million sperm in a typical sample, these patients may have just two or three. Not 2 [million] or 3 million, literally two or three,' he said. 'But with the precision of the STAR system and the expertise of our embryologists, even those few can be used to successfully fertilize an egg.' It's estimated that the male partner accounts for up to 40% of all infertility cases in the United States, and up to 10% of men with infertility are azoospermic. 'This often is a really heartbreaking and shocking and unexpected diagnosis,' Williams said. 'Most men who have azoospermia feel completely healthy and normal. There's no impairment of their sexual function, and the semen looks normal, too. The difference is that when you look at it under a microscope, instead of seeing literally hundreds of millions of sperm swimming, you just see cell debris and fragments but no sperm.' Treatment options for azoospermia traditionally have included uncomfortable surgery to retrieve sperm directly from a patient's testes. 'A part of the testes gets removed and broken into little pieces, and you try to find sperm there,' Williams said. 'It's invasive. You can only do it a couple of times before there could be permanent scarring and damage to the testes, and it's painful.' Other treatment options may include prescription hormone medications – but that will be effective only if the person has an imbalance of hormones. If no other treatment options are successful, couples may use donor sperm to have a child. Williams said the STAR method can be a new option. 'It really was a team effort to develop this, and that's what really drove and motivated everybody, the fact that you can now help couples who otherwise couldn't have that opportunity,' he said. Although the method is currently available only at the Columbia University Fertility Center, Williams and his colleagues want to publish their work and share it with other fertility centers. Using the STAR method to find, isolate and freeze sperm for a patient would cost a little under $3,000 total, he said. 'Infertility is unique in a way in that it's such an ancient part of the human experience. It's literally biblical. It's something we've had to contend with through all of human history,' he said. 'It's amazing to think that the most advanced technologies that we currently have are being used to solve this really ancient problem.' It's not the first time doctors have turned to AI to help men with azoospermia. A separate research team in Canada built an AI model that could automate and accelerate the process of searching for rare sperm in samples from men with the condition. 'The reason AI is so well-suited for this is AI really relies on learning – showing it an image of what a sperm looks like, what the shape is, what characteristics it should have – and then being able to use that learning algorithm to help identify that specific image that you're looking for,' said Dr. Sevann Helo, a urologist at Mayo Clinic with specialty interest in male infertility and male sexual dysfunction, who was not involved in the STAR method or the research in Canada. 'It's very exciting,' she said. 'AI, in general, at least in the medical community, I think is a whole new landscape and really will revolutionize the way we look at a lot of problems in medicine.' The STAR method is a novel approach to identifying sperm, but AI has been used in many other ways within fertility medicine too, said Dr. Aimee Eyvazzadeh, a San Francisco-based reproductive endocrinologist and host of the podcast 'The Egg Whisperer Show.' 'AI is helping us see what our eyes can't,' Eyvazzadeh, who was not involved in the development of STAR, wrote in an email. For instance, AI algorithms, such as one called Stork-A, have been used to analyze early-stage embryos and predict with 'surprising accuracy' which ones are likely to be healthy. Another AI tool, CHLOE, can assess the quality of a woman's eggs before she may freeze them for future use. 'AI is being used to personalize IVF medication protocols, making cycles more efficient and less of a guessing game. It's also helping with sperm selection, identifying the healthiest sperm even in difficult samples. And AI can now even predict IVF success rates with more precision than ever before, using massive data sets to give patients personalized guidance,' Eyvazzadeh said. 'The common thread? Better decisions, more confidence, and a more compassionate experience for patients.' The new STAR system is 'a game-changer,' she said. 'AI isn't creating sperm – it's helping us find the rare, viable ones that are already there but nearly invisible,' she said. 'It's a breakthrough not because it replaces human expertise, but because it amplifies it – and that's the future of fertility care.' But there is also a growing concern that the rushed application of AI in reproductive medicine could give false hope to patients, said Dr. Gianpiero Palermo, professor of embryology and director of andrology and assisted fertilization at Weill Cornell Medicine. 'AI is gaining a lot of traction nowadays to offer unbiased evaluation on embryos by looking at embryo morphology,' Palermo said in an email. 'However, current available models are still somewhat inconsistent and require additional validation.' Palermo said the STAR approach needs to be validated and would still require human embryologists to pick up sperm and inject them into an egg to create an embryo for patients undergoing IVF. 'Maybe the AI addition may help to retrieve the spermatozoon a little faster and maybe one more than the embryologist,' said Palermo, who was not involved in the development of STAR but was the first to describe the method of injecting sperm directly into an egg. Since he pioneered that method, it has become the most-utilized assisted reproductive technology in the world. 'In my opinion, this approach is faulty because inevitably some men will have no spermatozoa,' Palermo said of the STAR method, 'doesn't matter how their specimens are screened whether by humans or a machine.'

Scientists Caught Sperm Defying One of Newton's Laws of Physics
Scientists Caught Sperm Defying One of Newton's Laws of Physics

Yahoo

time23-06-2025

  • Science
  • Yahoo

Scientists Caught Sperm Defying One of Newton's Laws of Physics

Human sperm can swim through surprisingly viscous fluids with ease – and they seemingly defy Newton's third law of motion to do so. To figure out how they slither through substances that should, in theory, resist their movement, a team led by Kenta Ishimoto, a mathematical scientist at Kyoto University, investigated the motions of sperm and other microscopic biological swimmers a few years ago. When Sir Isaac Newton conceived his now-famed laws of motion in 1686, he sought to explain the relationship between a physical object and the forces acting upon it with a few neat principles that, it turns out, don't necessarily apply to microscopic cells wriggling through sticky fluids. Newton's third law can be summed up as "for every action, there is an equal and opposite reaction". It signifies a particular symmetry in nature where opposing forces act against each other. In the simplest example, two equal-sized marbles colliding as they roll along the ground will transfer their force and rebound based on this law. However, nature is chaotic, and not all physical systems are bound by these symmetries. So-called non-reciprocal interactions show up in unruly systems made up of flocking birds, particles in fluid – and swimming sperm. These motile agents move in ways that display asymmetric interactions with the animals behind them or the fluids that surround them, forming a loophole for equal and opposite forces to skirt Newton's third law. Because birds and cells generate their own energy, which gets added to the system with each flap of their wings or movement of their tails, the system is thrust far from equilibrium, and the same rules don't apply. In their study published in October 2023, Ishimoto and colleagues analyzed experimental data on human sperm and also modeled the motion of green algae, Chlamydomonas. Both swim using thin, bendy flagella that protrude from the cell body and change shape, or deform, to drive the cells forward. Highly viscous fluids would typically dissipate a flagellum's energy, preventing a sperm or single-celled algae from moving much at all. And yet somehow, the elastic flagella can propel these cells along without provoking a response from their surroundings. The researchers found that sperm tails and algal flagella have an 'odd elasticity', which allows these flexible appendages to move about without losing much energy to the surrounding fluid. But this property of odd elasticity didn't fully explain the propulsion from the flagella's wave-like motion. So from their modeling studies, the researchers also derived a new term, an odd elastic modulus, to describe the internal mechanics of flagella. "From solvable simple models to biological flagellar waveforms for Chlamydomonas and sperm cells, we studied the odd-bending modulus to decipher the nonlocal, nonreciprocal inner interactions within the material," the researchers concluded. The findings could help in the design of small, self-assembling robots that mimic living materials, while the modeling methods could be used to better understand the underlying principles of collective behavior, the team said. The study was published in PRX Life. An earlier version of this article was published in October 2023. A Cracked Piece of Metal Self-Healed in Experiment That Stunned Scientists A Fifth Force of Nature May Have Been Discovered Inside Atoms Strange Radio Signals Detected Emanating From Deep Under Antarctic Ice

Hopes of fatherhood: UBC scientists on frontier of high-tech male infertility research
Hopes of fatherhood: UBC scientists on frontier of high-tech male infertility research

CBC

time15-06-2025

  • Health
  • CBC

Hopes of fatherhood: UBC scientists on frontier of high-tech male infertility research

Social Sharing A team of researchers at the University of British Columbia (UBC) is using artificial intelligence in an effort to detect hard-to-find sperm and 3D bioprinting technology with the ultimate goal of growing sperm in the lab — technologies they say could eventually help men with infertility become parents. The research, led by Dr. Ryan Flannigan, a urologist and associate professor at UBC, is aimed at addressing a "severe form" of male infertility called non-obstructive azoospermia (NOA), in which the body produces little to no sperm. It's a condition that affects about one in 100 men, many of whom are survivors of childhood cancer, according to Flannigan. "There's a big problem with infertility: it's so common," he told CBC's The Early Edition. "Something that I see time and time again is just how much of an emotional toll having challenges with infertility is." According to a UBC media release, about two thirds of male pediatric cancer survivors will face infertility in adulthood, due to the effects of radiation or chemotherapy. Globally, one in six couples struggles to conceive, and male infertility, broadly, plays a role in about half of those cases. AI to detect rare sperm Currently, the only treatment for NOA involves surgically extracting testicular tissue and searching for hard-to-find sperm under a microscope — a tedious process, says Flannigan, that can take hours and still might end in failure. "It's ... looking for a needle in a haystack," he says. "Right now, we're able to find sperm about 50 per cent of the time. We ideally need to find at least one sperm per each egg, among millions of other cells, which takes hours." To improve the odds, Flannigan says he and UBC engineering professor Hongshen Ma have developed an AI-powered tool that scans microscopic images to flag viable sperm for use in in vitro fertilization (IVF). The technology is still a long way from being available for people struggling with male infertility — Flannigan expects clinical trials for the AI tool could begin within the next three to five years. Lab-grown sperm for those without options But for people who produce no sperm at all, including children who undergo cancer treatment before puberty and are unable to store sperm, a more experimental avenue is underway: lab-grown sperm. In what the UBC media release calls a world-first, Flannigan and team have bioprinted a model of human testicular tissue using stem cells and a specialized gel-like "bio-ink." The printed structure replicates the tiny tubes in the testes where sperm are normally produced. These bioprinted 'mini testicles' are encased in a special gel filled with specific nutrients and vitamins to help them mature. According to researchers, some of the cells have already begun showing signs consistent with the early stages of puberty — "a time when sperm production starts occurring in the human body." "What we're trying to do with 3D bioprinting is recreate what's happening in a healthy testicle as accurately as we can," said Flannigan. "If we can determine what the cells need to progress through all the phases of sperm production, we can use that knowledge to figure out how to create sperm for a patient with NOA," says Dr. Flannigan. The work is being supported by experts in microfluidics — a system that manipulates a small amount of fluids — and cancer biology at UBC and the University of Victoria, who are helping identify the molecular conditions required for sperm to develop. Still, researchers acknowledge there are significant challenges ahead. According to the UBC release, sperm production is a "highly complicated process" involving multiple cell types, complex anatomical structures, making it a task that demands collaborative, multidisciplinary research. 'Life-changing' potential, but questions remain Laura Spencer, a fertility coach in Vancouver, has experienced the emotional toll of infertility first-hand in her own family. "I've gone through infertility — male factor infertility in particular — and it's devastating," she told CBC News. "There's nothing quite like it." She said this latest development in treating male infertility could potentially be life-changing for many couples. WATCH | An at-home test is in the works to measure male fertility: An at-home test is in the works to measure male fertility 3 months ago Duration 1:46 Researchers at the University of Waterloo are working on an at-home test, which is a cheaper alternative to other tests. It usually involves examining the sperm under a microscope in a lab, but this one will allow people to check right at home. Sushanta Mitra, a professor of mechanical and mechatronics engineering, is one of the researchers behind the study. "This shows a lot of promise for people who might not have the ability to try and conceive … they might actually be able to have a baby." Spencer says male infertility remains a taboo subject, despite being a factor in about half of all couples struggling to conceive. She hopes this research not only opens new medical doors, but also breaks down stigma. "There is a lot of shame and sometimes guilt around that," she said. "I'm always grateful when the conversation turns to infertility and when it's normalized." "There will definitely need to be education around this," she added. "We don't know what the long term consequences are of this technology. Are there any birth defects that are possible? What about when they grow up? Like we don't know. This is just so new." As for concerns about the safety of AI or stem cell-based procedures, Flannigan says the research team is taking a cautious approach.

'There's a huge amount that we don't understand': Why sperm is still so mysterious
'There's a huge amount that we don't understand': Why sperm is still so mysterious

BBC News

time14-06-2025

  • Science
  • BBC News

'There's a huge amount that we don't understand': Why sperm is still so mysterious

How do sperm swim? How do they navigate? What is sperm made of? What does a World War Two codebreaker have to do with it all? The BBC untangles why we know so little about this mysterious cell. With every heartbeat, a man can produce around 1,000 sperm – and during intercourse, more than 50 million of the intrepid swimmers set out to fertilise an egg. Only a few make it to the final destination, before a single sperm wins the race and penetrates the egg. But much about this epic journey – and the microscopic explorers themselves – remains a mystery to science. "How does a sperm swim? How does it find the egg? How does it fertilise the egg?" asks Sarah Martins da Silva, clinical reader of diabetes endocrinology and reproductive biology at the University of Dundee in the UK. Almost 350 years on from the discovery of sperm, many of these questions remain surprisingly open to debate. Using newly developed methods, scientists are now following sperm on their migration – from their genesis in the testes all the way to the fertilisation of the egg in the female body. The results are leading to groundbreaking new discoveries, from how sperm really swim to the surprisingly big changes that occur to them when they reach the female body. "Sperm – or spermatozoa – are 'very, very different' from all other cells on Earth," says Martins da Silva. "They don't handle energy in the same way. They don't have the same sort of cellular metabolism and mechanisms that we would expect to find in all other cells." Due to the huge range of functions demanded of spermatozoa, they require more energy than other cells. Plus sperm need to be flexible, to be able to respond to environmental cues and varying energetic demands during ejaculation and the journey along the female tract, right up until fertilisation. Sperm are also the only human cells which can survive outside the body, Martins da Silva adds. "For that reason, they are extraordinarily specialised." However, due to their size these tiny cells are very difficult to study, she says. "There's a lot we know about reproduction – but there's a huge amount that we don't understand." One fundamental question that remained unanswered over almost 350 years of research: what exactly are sperm? "The sperm is incredibly well-packaged," says Adam Watkins, associate professor in reproductive and developmental physiology at Nottingham University in the UK. "We typically thought of the sperm as a bag of DNA on a tail. But as we've started to realise, it's quite a complex cell – there's a lot of [other] genetic information in there." The science of sperm began in 1677, when Dutch microbiologist Antoni van Leeuwenhoek looked through one of his 500 homemade microscopes and saw what he called "semen animals". He concluded, in 1683, that it wasn't the egg that contained the miniature and entire human, as previously believed, but that man comes "from an animalcule in the masculine seed". By 1685, he had decided that each spermatozoon contains an entire miniature person, complete with its own "living soul". Almost 200 years later, in 1869, Johannes Friedrich Miescher, a Swiss physician and biologist, was studying human white blood cells collected from pus left on soiled hospital bandages when he discovered what he called "nuclein" inside the nuclei. The term "nuclein" was later changed to "nucleic acid" and eventually became "deoxyribonucleic acid" – or "DNA". Aiming to further his studies of DNA, Miescher turned to sperm as his source. Salmon sperm, in particular, were "an excellent and more pleasant source of nuclear material" due to their particularly large nuclei. He worked in freezing temperatures, keeping laboratory windows open, in order to avoid deterioration of salmon sperm. In 1874, he identified a basic component of the sperm cell that he called "protamine". It was the first glimpse of the proteins that make up sperm cells. It took another 150 years, however, for scientists to identify the full protein contents of sperm. Since then, our understanding of sperm has moved on leaps and bounds. But much still remains a mystery, says Watkins. As scientists have started to better understand early embryonic development, he adds, they are realising that sperm doesn't just pass the father's chromosomes on, but also epigenetic information, an extra layer of information that affects how and when the genes should be used. "It can really influence how the embryo develops and potentially the lifelong trajectory of the offspring that those sperm generate," says Watkins. Sperm cells begin to form from puberty onwards, made in vessels within the testicles called seminiferous tubules. "If you look inside the testes where the sperm are made, it starts as just a round cell that looks pretty much like anything else," says Watkins. "Then it undergoes this dramatic change where it becomes a sperm head with a tail. No other cell within the body changes its structure, its shape, in such a unique way." It takes sperm about nine weeks to reach maturity within the male body. Unejaculated sperm cells eventually die and are reabsorbed into the body. But the lucky ones are ejaculated – and then the adventure begins. After ejaculation, each of these tiny cells must propel themselves forward (alongside their 50 million competitors) using their tail-like appendages to swim for the egg. And while you may have seen plenty of videos of tadpole-like sperm swimming around, in fact scientists are only just beginning to understand how sperm really swim. It was previously thought that the sperm's tail – or flagellum – moved side to side like that of a tadpole. But in 2023, researchers at the University of Bristol in the UK found that sperm tails follow the same template for pattern formation discovered by mathematician and World War Two codebreaker Alan Turing. In 1952, Turing realised that chemical reactions can create patterns. He proposed that two biological chemicals moving and reacting with each other could be used to explain some of nature's most intriguing biological pattern formations – including those found in fingerprints, feathers, leaves and ripples in sand – an idea known as his "reaction-diffusion" theory. Using 3D microscopy, the Bristol researchers discovered that a sperm's tail – or flagellum – undulates, generating waves that travel along the tail to drive it forward. This is significant as understanding how sperm move can help scientists to understand male fertility. So, now the sperm are on the move. They travel through the cervix, into the womb and up the oviducts – tubes that eggs travel down to reach the womb, known as the fallopian tubes in human females – in search of the egg. But here we hit another gap in knowledge, because scientists don't fully understand how sperm actually find their way to the egg. Spermatozoa which are healthy and take the right route are rare. Many take a wrong turn in the maze that is the female body – and never even make it near the goal line. For the ones that do find their way to the fallopian tubes, scientists think that they may be guided by chemical signals emitted by the egg. One recent theory is that sperm may use taste receptors to "taste" their way to the egg. Once the sperm find the egg, the challenge is not over. The egg is surrounded by a triplicate coat of armour: the corona radiata, an array of cells; the zona pellucida, a jelly-like cushion made of protein; and finally the egg plasma membrane. The sperm cells have to fight their way through all the layers, using chemicals contained in their acrosome, a cap-like structure on the head of a sperm cell containing enzymes that digest the egg cell coating. However, what prompts the release of these enzymes remains a mystery. Next the sperm use a spike on their "head" to try and break their way in to the egg, thrashing their tails to force themselves forwards. Finally, if one sperm makes contact with the egg membrane, it is engulfed and can complete fertilisation. Human cells are diploid. This means they contain two complete sets of chromosomes, one from each parent. If more than one sperm were to fuse with the egg, a condition called polyspermy would arise. Nondiploid cells – ones with the incorrect number of chromosomes – would develop, a condition lethal to a growing embryo. To prevent this from happening, once a sperm cell has made contact with it, the egg quickly employs two mechanisms. First, its plasma membrane rapidly depolarises – meaning it creates an electrical barrier that further sperm cannot cross. However, this only lasts a short time before returning to normal. This is where the cortical reaction comes in. A sudden release of calcium causes the zona pellucida – the egg's "extracellular coat" – to become hardened, creating an impenetrable barrier. So, of millions of sperm that set out on the journey, only one – at most – gets to do its job. The sperm's epic journey culminates in its fusion with the egg. Today, researchers are still attempting to uncover the identity and role of cell surface proteins that could be responsible for sperm-egg recognition, binding and fusion. In recent years, several proteins have been identified – albeit in mice and fish – as being crucial for this process, but many of the molecules involved remain unknown. So, for now, how the sperm and egg recognise each other, and how they fuse are yet more mysteries that remain unsolved. One way researchers are hoping to shed light on sperm is by studying species other than our own, says Scott Pitnick, a professor of biology at Syracuse University in New York. Human sperm cells are microscopic, so we can't see them with the naked eye. But some fruit fly species produce sperm cells 20 times their own body length. That would be like a man producing sperm the length of a 40m (130ft) python. Pitnick engineers the heads of fruit fly sperm so that they glow. This means he can watch them as they travel through dissected female fly reproductive tracts, revealing new details about fertilisation at the molecular level. "Why do males in some species make a few giant sperm?" asks Pitnick. "The answer, it turns out, is because females have evolved reproductive tracts that favour them." That's "not really much of an answer", he adds, because it's just the redirects the question: why have females evolved this way? "We still don't understand that at all." But it does teach us that sperm as they exist in the male body is only half the story, says Pitnick. "There's a massive sex bias historically in science. There's been this obscenely biased male focus on male traits. But it turns out that what's driving the system is female evolution – and males are just trying to keep up." Sperm, Pitnick says, are the most diverse and rapidly evolving cell type on Earth. Why sperm have undergone such dramatic evolution is a mystery that has stumped biologists for more than a century. "It turns out the female reproductive tract is this incredibly, rapidly evolving environment," says Pitnick, "and we don't know much about what sperm do inside the female. That is the big, hidden world. I think the female reproductive tract is the greatest unexplored frontier for sexual selection, theory and speciation [the process by which new species are formed]." The fruit fly's long-tailed sperm, suggests Pitnick, could be considered an ornament – much like a deer's antlers or a peacock's tail. Ornaments are a "sort of a weapon in evolution", explains Pitnick. More than just a defence from predators, ornaments like antlers and horns often have two roles to play. "A lot of these weapons are about sex, and usually male-male competition. The [fruit fly's] long sperm flagellum really meets the definitional criteria of an ornament. We think the female tract has traits that bias fertilisation in favour of some sperm phenotypes over others." We know a lot about pre-mating sexual selection, Pitnick says. "Say, it's prairie chickens dancing out on a grassland, or a bird of paradise displaying in a rainforest. It's motion, it's colour, it's smells?" Processing this sensory input, explains Pitnick, leads to decision making – whether the pair mate or not. But, Pitnick says, the sexual selection that goes on inside the female after mating – and how this drives the evolution of sperm – largely remains a mystery. "We still understand very little about the genetics of ornaments and preferences," he says. To fully understand sperm, we need to think about how the entire lifecycle of the sperm – and the female body, explains Pitnick, plays a huge role in the sperm's development. "Sperm are not mature when they finish developing in the testes, they're not done developing." Complex – and critical – interactions occur between the sperm and the female reproductive tract, he says. "We're now spending a lot of time studying what we call post-ejaculatory modifications to sperm across the whole animal kingdom." Even as scientists are unravelling the many and varied processes a sperm goes through in order to achieve fertilisation, other research is leading to real concern about the current state of human sperm. Men produce close to a trillion sperm during one lifetime, so it might be hard to imagine that sperm are in trouble. But research suggests sperm counts – the number of sperm in a sample of semen – are tumbling globally and the decline appears to be accelerating. More like this:• How pollution is causing a male fertility crisis• Pre-eclampsia: The deadly mystery scientists can't solve• Fewer than half of IVF cycles are successful. These scientists are trying to change that According to a 2023 report published by the World Health Organisation (WHO), around one in six adults worldwide experience infertility – and male infertility contributes to roughly half of all cases. (It's also worth noting that many people around the world are not having as many children as they want for other reasons too, such as the prohibitive cost of parenthood, as a recent United Nation population Fund report highlighted). Pollution, smoking, alcohol, poor diet, lack of exercise and stress are all thought to impact male infertility. Yet for the majority of men with fertility problems, the cause remains unexplained. (Read more about the decline in sperm quality around the world). "With all those moving parts, there are so many things that could go wrong," says Hannah Morgan, a post-doctoral research associate in maternal and fetal health at the University of Manchester, UK. "It could be a mechanism: it doesn't swim very well, so it can't get to the egg. Or it could be something more intricate within the head of the sperm, or other regions of the sperm. It's so specialised in so many different ways, that lots of little things can go wrong." One way to see if a man may be infertile is to look inside the sperm, says Morgan. "How does the DNA look? How is it packaged? How fragmented is it? To break open the sperm, there's a whole range of stuff you could look at. But what is a good or bad measurement? We don't actually know." Perhaps by unravelling the mystery of sperm and how they function, Morgan says, we might begin to understand male infertility too. -- For trusted insights into better health and wellbeing rooted in science, sign up to the Health Fix newsletter, while The Essential List delivers a handpicked selection of features and insights. For more science, technology, environment and health stories from the BBC, follow us on Facebook, X and Instagram.

Michelle Obama peddles dangerous theory about what REALLY gives babies autism... then immediately regrets it
Michelle Obama peddles dangerous theory about what REALLY gives babies autism... then immediately regrets it

Daily Mail​

time28-05-2025

  • General
  • Daily Mail​

Michelle Obama peddles dangerous theory about what REALLY gives babies autism... then immediately regrets it

Michelle Obama pushed a theory suggesting a correlation between older sperm and autism diagnoses, before immediately backpedaling on the remark. The former first lady made the shocking remark on Wednesday's episode of her podcast IMO with Michelle Obama & Craig Robinson, which she co-hosts with her older brother. The duo were discussing women's health issues with OBGYN Dr. Sharon Malone, when Obama seemingly took aim at President Donald Trump and the vaccine skeptics in his cabinet. Obama asked Malone if there was a 'connection between aging sperm and birth defects', before alleging that Republicans would 'cut out research on that'. Malone replied: 'There is some anecdotal data that says older sperm. 'So we should tell some people, maybe it's the old sperm, maybe it's not the vaccine that's causing the autism, you know? Why don't you look at that?' Obama joined in, joking that 'they'll never let that secret out'. 'That may be the key behind all the defunding everything. Then old men can keep marrying 20-year-olds,' she said, adding: 'It's like, "I'll give you the baby you want".' But she appeared to immediately regret the remark and turned to her production crew to say, 'We don't have to keep that in.' Trump's HHS Secretary Robert F. Kennedy Jr. has been known to peddle many conspiracy theories, including that chemicals in water are making children question their gender identity and that vaccines cause autism. The Centers for Disease Control and Prevention (CDC), however, states that 'studies have shown that there is no link between receiving vaccines and developing autism spectrum disorder'. Obama's commentary appeared to take direct aim at RFK's vaccine beliefs, as well as his age. Kennedy, 71, is married to actress Cheryl Hines, who is 12 years his junior. Although the pair do not share any children together, RFK fathered six children with his two ex-wives. His eldest is 40 and his youngest 23. The remark may have also been aimed at Trump, who became the oldest person to be elected president following his 2024 election victory. Trump, 78, has five children of his own, including 19-year-old Barron Trump, whom he shares with First Lady Melania Trump. Liberal trolls have suggested that Barron, whose father was 60 when he was born, may have autism - a rumor that the first lady quashed in her memoir last year. 'There is nothing shameful about Barron is not autistic,' she wrote. Obama's podcast episode was released just one day after RFK's bombshell announcement that Covid-19 vaccines would no longer be recommended for healthy children and pregnant women. The move reverses previous guidance which recommended the Covid vaccine to everyone aged six months old and over. In a video on X revealing the announcement, RFK Jr said: 'Last year, the Biden administration urged healthy children to get another Covid shot despite the lack of any clinical data to support the repeat booster strategy in children.' RFK Jr said he 'couldn't be more pleased' to make the announcement, adding that it was 'common sense' and 'good science'. The recommendation for the Covid vaccine for young and healthy individuals has long been criticized, given that the groups face a low risk of hospitalization and death from the virus. There are also concerns over side effects linked to the shots, including myocarditis -or heart inflammation - which is rare but more common among young adults. The FDA is also reportedly re-analyzing whether the evidence supports boosting healthy people under 65 against Covid.

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