Tag: Women and Girls

Mayim Bialik Wants the ‘Jeopardy!’ Job. Is She ‘Neutral’ Enough?

Alex Trebek projected impartiality. Bialik has questioned vaccines, endorsed a disputed brain supplement and weighed in on hot-button issues.

After Lives Fraught With Pain, Housing That Says ‘You’re Worthy’

Women who went to prison for killing their abusive partners are starting over at Home Free, an apartment complex created by design volunteers in San Francisco.

Is the Forced Contraception Alleged by Britney Spears Legal?

The United States has a dark history of court-sanctioned sterilization, but more recent rulings and legislation suggest it would violate a basic right.

Among the stunning assertions that the pop star Britney Spears made to a Los Angeles probate judge this week, as she sought to end her protracted conservatorship, was one that shook experts in guardianship law and reproductive rights deeply. She said a team led by her father, who is her conservator, prevented her from having her IUD removed because the team did not want her to have more children.

“Forcing someone to be on birth control against their will is a violation of basic human rights and bodily autonomy, just as forcing someone to become or stay pregnant against their will would be,” said Ruth Dawson, a principal policy associate at the Guttmacher Institute, a research group that supports reproductive rights.

Court-condoned compelled contraception is rare in conservatorship. But the specter it raises — forced sterilization — does have a grim, extensive history in the United States, especially against poor women, women of color and inmates. In the early 20th century, the state-sanctioned practice was upheld by the United States Supreme Court.

Although the court moved away from that position in the 1940s, and consensus arose through the growing canon on informed consent that forced sterilization was inhumane, the practice continued to be quietly tolerated.

Finally, by the end of the 1970s, most states had repealed laws authorizing sterilization, although allegations of forced hysterectomies and tubal ligations on women in immigrant detention centers continue to be raised. It wasn’t until 2014 that California formally banned the sterilization of female inmates without consent.

The scant law on the question in conservatorship indicates what an outlier the Spears case may be. In 1985, the California Supreme Court denied the petition of guardian parents of a 29-year-old woman with Down syndrome who wanted her to undergo a tubal ligation.

Typically, a conservator has temporary control over the finances and even medical care of an incapacitated person. Experts underscored that Ms. Spears’s assertion is unverified. But if it’s accurate, they said, the most likely rationale, however suspect, might be that Jamie Spears, her father, wants to protect her finances from a baby’s father, potentially her boyfriend, who is reportedly at odds with Mr. Spears.

If a guardian fears that a ward will make financially unwise choices, “the remedy is not to say they can’t procreate,” said Sylvia Law, a health law scholar at New York University School of Law. “It’s unspeakable.”

According to experts in trust and estate law, the handful of cases in which a guardian, usually a parent, has asked a court to order contraception involved severely disabled children.

“Such a child would lack the capacity to understand that a penis and vagina could make a baby,” said Bridget J. Crawford, an expert on guardianship law at Pace University law school. “And that certainly is not the Britney Spears case.”

Eugenics was a leading rationale for female sterilization. In the 1927 case Buck v. Bell, the Supreme Court upheld the right to sterilize a “feeble-minded” woman who had been committed to a state mental institution, with Justice Oliver Wendell Holmes infamously writing, “Three generations of imbeciles are enough.”

Although the opinion was never formally overturned, in a 1942 case, Skinner v. Oklahoma, which challenged forced sterilization of certain convicted criminals, Justice William O. Douglas, writing for a unanimous court, said that the right to procreate was fundamental. “Any experiment the state conducts is to his irreparable injury,” he wrote. “He is forever deprived of a basic liberty.”

While Ms. Spears has not been sterilized, Ms. Crawford said, if she is being prevented from getting her IUD removed, that would be a proxy for sterilization, in particular because she testified that she wanted to bear more children.

Melissa Murray, who teaches reproductive rights and constitutional law at N.Y.U. law school, pointed to another unnerving element in the allegation by Ms. Spears, who, at 39, has been under her father’s guardianship for 13 years. Ms. Murray said that Ms. Spears, an adult, appeared to be living a legally constructed childhood.

“It’s unusual that her father is making the kinds of decisions we’d expect a parent to make for a teenager,” she added.

Is the Forced Contraception Alleged by Britney Spears Legal?

The United States has a dark history of court-sanctioned sterilization, but more recent rulings and legislation suggest it would violate a basic right.

Among the stunning assertions that the pop star Britney Spears made to a Los Angeles probate judge this week, as she sought to end her protracted conservatorship, was one that shook experts in guardianship law and reproductive rights deeply. She said a team led by her father, who is her conservator, prevented her from having her IUD removed because the team did not want her to have more children.

“Forcing someone to be on birth control against their will is a violation of basic human rights and bodily autonomy, just as forcing someone to become or stay pregnant against their will would be,” said Ruth Dawson, a principal policy associate at the Guttmacher Institute, a research group that supports reproductive rights.

Court-condoned compelled contraception is rare in conservatorship. But the specter it raises — forced sterilization — does have a grim, extensive history in the United States, especially against poor women, women of color and inmates. In the early 20th century, the state-sanctioned practice was upheld by the United States Supreme Court.

Although the court moved away from that position in the 1940s, and consensus arose through the growing canon on informed consent that forced sterilization was inhumane, the practice continued to be quietly tolerated.

Finally, by the end of the 1970s, most states had repealed laws authorizing sterilization, although allegations of forced hysterectomies and tubal ligations on women in immigrant detention centers continue to be raised. It wasn’t until 2014 that California formally banned the sterilization of female inmates without consent.

The scant law on the question in conservatorship indicates what an outlier the Spears case may be. In 1985, the California Supreme Court denied the petition of guardian parents of a 29-year-old woman with Down syndrome who wanted her to undergo a tubal libation.

Typically, a conservator has temporary control over the finances and even medical care of an incapacitated person. Experts underscored that Ms. Spears’s assertion is unverified. But if it’s accurate, they said, the most likely rationale, however suspect, might be that Jamie Spears, her father, wants to protect her finances from a baby’s father, potentially her boyfriend, who is reportedly at odds with Mr. Spears.

If a guardian fears that a ward will make financially unwise choices, “the remedy is not to say they can’t procreate,” said Sylvia Law, a health law scholar at New York University School of Law. “It’s unspeakable.”

According to experts in trust and estate law, the handful of cases in which a guardian, usually a parent, has asked a court to order contraception involved severely disabled children.

“Such a child would lack the capacity to understand that a penis and vagina could make a baby,” said Bridget J. Crawford, an expert on guardianship law at Pace University law school. “And that certainly is not the Britney Spears case.”

Eugenics was a leading rationale for female sterilization. In the 1927 case Buck v. Bell, the Supreme Court upheld the right to sterilize a “feeble-minded” woman who had been committed to a state mental institution, with Justice Oliver Wendell Holmes infamously writing, “Three generations of imbeciles are enough.”

Although the opinion was never formally overturned, in a 1942 case, Skinner v. Oklahoma, which challenged forced sterilization of certain convicted criminals, Justice William O. Douglas, writing for a unanimous court, said that the right to procreate was fundamental. “Any experiment the state conducts is to his irreparable injury,” he wrote. “He is forever deprived of a basic liberty.”

While Ms. Spears has not been sterilized, Ms. Crawford said, if she is being prevented from getting her IUD removed, that would be a proxy for sterilization, in particular because she testified that she wanted to bear more children.

Melissa Murray, who teaches reproductive rights and constitutional law at N.Y.U. law school, pointed to another unnerving element in the allegation by Ms. Spears, who, at 39, has been under her father’s guardianship for 13 years. Ms. Murray said that Ms. Spears, an adult, appeared to be living a legally constructed childhood.

“It’s unusual that her father is making the kinds of decisions we’d expect a parent to make for a teenager,” she added.

For Younger Women, High Blood Pressure May Carry Heightened Risks

Women, but not men, with even mildly elevated blood pressure in their early 40s were at increased risk for later heart disease and early death.

High blood pressure in younger people may be particularly hazardous for women, a new study suggests. The study found that women — but not men — with even mildly elevated blood pressure in their early 40s may be at substantially increased risk for later coronary disease and death.

In 1992, Norwegian researchers began studying 12,329 men and women whose average age was 41. They tracked their blood pressure and cardiovascular health for an average of 16 years.

At the start, high blood pressure was much less common in women than in men: 25 percent of women and 35 percent of men had stage 1 hypertension, which the American Heart Association defines as a reading of 130/80 to 139/89. (A reading under 120/80 is considered normal.) Fourteen percent of women and 31 percent of men had stage 2 hypertension, defined as 140/90 or higher. The women also had fewer risk factors for heart disease: They tended to have lower B.M.I.s and lower cholesterol levels, and fewer of them were smokers.

During the follow-up period, 1.4 percent of the women and 5.7 percent of the men had been hospitalized with or died from cardiovascular disease.

Compared with women who had normal blood pressure at the start of the study, those with stage 1 hypertension had more than double the risk of heart disease. In men, this association was statistically insignificant. The study, in the European Journal of Preventive Cardiology, controlled for diabetes, B.M.I., cholesterol, smoking and physical activity.

The authors acknowledge that the study had limitations. It was done in a small geographic area in Norway, and the subjects were primarily Caucasian. Moreover, the researchers had no information about hypertension treatment or the use of cholesterol-lowering drugs during the follow-up period.

Still, “the emerging evidence is that hypertension is worse for female hearts than for male hearts,” said the lead author, Dr. Ester Kringeland, an internal medicine specialist at the University of Bergen in Norway, “and the risk starts at a lower blood pressure level in women.”

Dr. Joyce M. Oen-Hsiao, an assistant professor of medicine at Yale who was not involved in the work, said, “It’s a well-designed study. Most of us just look at risk factors, and we never really break it down by gender. That’s the novelty of this paper — that there’s a statistical difference between men and women. And if we can replicate this finding in our more diverse population, it will change primary prevention.”

Current American Heart Association guidelines say that in otherwise healthy people, high blood pressure up to 130/80 can usually be managed with lifestyle changes. For readings from 130/80 to 139/89, the group recommends antihypertensive drugs, but only for people with other cardiovascular disease risk factors. At 140/90 or higher, medication is indicated in almost all cases. But the guidelines make no distinction between men and women.

Dr. Kringeland said that one reading, or a reading with a home blood pressure monitor, is not enough to make a diagnosis. “A doctor has to take three readings, then average the last two. And to diagnose hypertension, you need at least two visits to the doctor.”

The question of whether a healthy woman in her 40s with a reading of 130/80 should be treated with antihypertensive drugs is still not settled.

“In some women — those with diabetes, for example — treatment is indicated even at this level,” Dr. Kringeland said. “But in women who are otherwise healthy? We don’t have the answer yet. Blood pressure medicines have side effects, and you have to look at the risk-benefit ratio. We need more research about cardiac disease in women.”

How Asian Women Are Discovering New Confidence Through Self-Defense Training

On a warm April afternoon in Washington Square Park, I squared off with my friend Noelle, a petite Filipino policy researcher, and shoved her. She slapped the ground as she fell, landing seat-first with a dull thud. Dazed yet grinning, she braced both hands on the ground behind her, lifted her leg, angled her foot and kicked me in the shin. Then she got up, brushed herself off and let me do the same.

This sparring match was part of a private self-defense class I organized for my Asian friends in New York. Reports of vicious attacks on Asians, especially women and older adults, had filled my news feeds since February, when the media began covering anti-Asian hate incidents that rose during the pandemic.

For the first time in 12 years of living comfortably in Manhattan, I became afraid to walk the city’s streets as a Filipino woman. Whenever I stepped outside, I thought of the attacker who shoved an older man to the sidewalk in Oakland or the one who senselessly beat and kicked a Filipino woman near Times Square. I wondered what I would do if it happened to me.

So I organized the class, hoping my friends and I would pick up a few tricks and perhaps emerge feeling less helpless. Psychology researchers have found that self-defense training can increase confidence in women, improve mental health and decrease feelings of vulnerability. But I have since learned that self-defense offers much more than skills and confidence; it can foster a powerful sense of agency.

Michael Salgarolo, a 29-year-old doctoral candidate, clasps hands before jerking them upward to escape the author’s grip (left) on his wrist.Jutharat Pinyodoonyachet for The New York Times
Bea Clemente, a 24-year-old marketing manager, aims a kick at George Ocampo, a 26-year-old creative strategist, from a defensive position on the ground.Jutharat Pinyodoonyachet for The New York Times

Self-defense begins in the body.

There are many self-defense styles out there. Some are based on traditional martial arts like taekwondo, karate and judo, while others combine moves from other fighting systems, including Krav Maga and street combat. But most types of self-defense teach you how to avoid dangerous situations and harm an attacker, so that you can make a quick getaway.

One type, called empowerment self-defense, trains you not only to defend yourself against violence but also to interrupt assaults in their early stages by making confident eye contact and saying things like “Back up, I don’t want any trouble.” If that doesn’t work, it may be time to cause some pain.

An essential step is preparing for the shock of an attack. In promotional videos for an organization called DC Impact Self Defense, students yell at the top of their lungs while hitting pads or instructors in cushioned suits, simulating their reaction to a real-life assault.

During any fight, most people feel incredible fear and anger, which triggers an adrenaline response that makes many freeze, said Jill Cermele, a psychology professor at Drew University in New Jersey, who studies the efficacy of self-defense and teaches empowerment self-defense.

With training, you can harness the adrenaline response to deliver a painful blow or make a quick getaway. And many self-defense skills can often be adapted for older people or those with disabilities. A walking cane, for example, can deliver a nasty blow.

“It’s the practice of doing that tells you, ‘You can do it.’ I know I can do it because I’ve done it before,” said Dr. Cermele.

The author places Mr. Salgarolo in a chokehold. Allie Quinones, the Brazilian jiu-jitsu instructor leading the course, said classes like these “empower other people to feel more confident in themselves — not just for self-defense, but personally.” 
The author places Mr. Salgarolo in a chokehold. Allie Quinones, the Brazilian jiu-jitsu instructor leading the course, said classes like these “empower other people to feel more confident in themselves — not just for self-defense, but personally.” Jutharat Pinyodoonyachet for The New York Times

There is robust evidence that supports the effectiveness of empowerment self-defense, but other approaches may be helpful too, said Jocelyn Hollander, an expert on the prevention of violence against women and a sociologist at the University of Oregon. In late April, I took a class based on a form of street fighting karate that the Chinese Hawaiian Kenpo Academy, in the East Village, offered for free to Asian-Americans over Zoom. The school’s founder, an ex-Marine named Jack Shamburger, taught us how to strike the soft parts of a perpetrator’s face — eyes, nose, ears — with the part of the fist you would slam down on a table, calling it the “hammer fist.”

We kicked an imaginary attacker in the scrotum, a target that could make him vomit, said Mr. Shamburger. He also taught us how to use our cellphone as a weapon, holding it with two hands and thrusting its edge into a person’s throat. I practiced these moves on a make-believe assailant for over an hour, lodging them into my muscle memory. If I ever needed to use them, I would be prepared.

Self-defense is a mindset.

In the weeks following the two classes, I was still afraid of being attacked, but I felt better equipped to protect myself. More than anything, I felt newly aware of my body and its potential.

This confidence, it turns out, is protective. Perpetrators seek out easy targets, like people who scurry around quietly with their head down, said Dr. Cermele. The confidence gained from self-defense, said Tsahi Shemesh, founder and lead instructor of Manhattan-based Krav Maga Experts, is a way to “remove the target from your back.”

A lasting benefit of self-defense training, experts said, is a concept related to confidence called “self-efficacy” — the belief that you can use your own skills to serve you when they’re needed. Some of the instructors I spoke to said that many people, especially women, come into their classes thinking they are incapable of defending themselves, only to discover that they can once they try.

Jonathan Shia, 33-year-old editor-in-chief of Cero Magazine, blocks a strike from Mackenzie Hamilton, a model, using his forearm.Jutharat Pinyodoonyachet for The New York Times

“It’s ‘I have confidence in my competence,’” said Karen Chasen, vice president of Prepare Inc., a violence prevention organization and member of Impact International, a group of organizations that teach empowerment self-defense.

Dr. Cermele was constantly afraid of being assaulted before she attended her first self-defense class in 1998. She felt physically vulnerable as a woman, and the stories that her trauma therapy clients told her filled her with fear. She avoided dark parking lots for fear of assault. In her first experience on the mat, a male instructor in a padded suit asked, “Hey, what time is it?” Dr. Cermele immediately started to cry. Feeling helpless in the face of an imminent assault was paralyzing.

But after just eight hours of training, Dr. Cermele was able to step out of her car in a parking lot at night for the first time without fear.

Self-defense is community defense too.

I wasn’t the only Asian person in the U.S. with the idea to learn how to defend myself this year. Self-defense schools in cities including New York and San Francisco have reported an uptick of Asian enrollment in their classes. Rej Joo, an instructor and program manager at the Center for Antiviolence Education in Brooklyn, said that since February at least half the students in their classes have been Asian women — a sharp rise from previous years, when he estimated they made up only about one in 10.

One reason Asians are learning self-defense is to “help change the stereotype that Asian-Americans won’t fight back or can’t fight back,” said Stanley Sue, an expert on Asian-American mental health and a psychology professor at Palo Alto University and the University of California, Davis. Asian-Americans are often stereotyped as the model minority or the “quiet, unobtrusive Asian,” he explained. These stereotypes may make perpetrators think we are easy targets and that we won’t defend ourselves. But self-defense is a way to flip the script.

Whether they’re held over Zoom, in a classroom or at a park, these classes also foster community. Linda Leu, a self-defense instructor and the executive director of Impact Bay Area, a chapter of Impact International, said it was a big deal for Asian people to be able to open up about their experiences with racism or violence in her classes because they are taught to avoid talking about unpleasant things.

“That can be detrimental to our mental health, our physical health,” she said.

In one lesson in our class, Noelle yanked my ponytail, stopping me in my tracks. Hair pulling, our instructor had told us, is a common attack against women. I reached behind my head with both hands, encircled my fingers around Noelle’s wrist, and stepped back to pull her arm toward my body. At that point, I could have snapped her wrist. Together with the other women in the class, I was astonished at the potency of this move — and that I could execute it.

I never want to be in that position again, or propped up by my hands on the sidewalk, about to deliver a kick. But if I need to, I’ll be ready to stick it where it hurts.


Yasmin Tayag is a science journalist and editor.

The Sperm-Count ‘Crisis’ Doesn’t Add Up

Reports of a decline in male fertility rely on flawed assumptions, a new study contends.

Male scientists have long waxed poetic on the contents of their testes. “Sperm is a drop of brain,” wrote the ancient Greek writer Diogenes Laërtius. Leonardo da Vinci drew the penis with a sperm duct that connected directly to the spinal cord. The 17th-century microscopist Antonie van Leeuwenhoek claimed that each sperm cell contained within it a folded-up human being waiting patiently to unfurl.

For nearly as long, scientists have fretted about sperm’s seemingly inevitable decline. Most recently, a series of alarming headlines — as well as a new book by an epidemiologist at Mount Sinai Medical Center in New York — warned that falling sperm counts might threaten the future of the human race. “It’s a global existential crisis,” said Shanna H. Swan, author of the book “Count Down.

Most of these headlines can be traced to an influential 2017 meta-analysis by Dr. Swan and others, which found that sperm counts in Europe, North America, Australia and New Zealand had plummeted by nearly 60 percent since 1973. The authors screened 7,500 sperm-count studies from around the world, weeded out most of them and ultimately analyzed 185 studies on 43,000 men worldwide.

They called the decline a “canary in the coal mine” for waning male reproductive health worldwide. Today, the authors would revise that statement. “There is clear and present alarm now,” said Dr. Hagai Levine, an epidemiologist at Hebrew University-Hadassah School of Public Health and a co-author on the 2017 review, in an email. “The canary is in trouble now.” Dr. Swan, in the same email, agreed.

Now a group of interdisciplinary researchers from Harvard and the Massachusetts Institute of Technology contend that fears of an impending Spermageddon have been vastly overstated. In a study published in May in the journal Human Fertility, they re-evaluated the 2017 review and found that it relied on flawed assumptions and failed to consider alternate explanations for the apparent decline of sperm.

In an interview, Sarah Richardson, a Harvard scholar on gender and science and the senior author on the new study, called the conclusion of the 2017 review “an astonishing and terrifying claim that, were it to be true, would justify the apocalyptic tenor of some of the writing.” Fortunately, she and her co-authors argue, there is little evidence that this is the case.

The 2017 authors were “methodologically rigorous” when it came to screening sperm-count studies for quality and consistency, Dr. Richardson and her colleagues write. However, even the data that passed muster was geographically sparse and uneven and often lacked basic criteria like the age of the men. Moreover, its authors took for granted that a single metric — sperm count — was an accurate predictor of male fertility and overall health.

The connection sounds logical: Without sperm, there can be no conception. That’s why sperm count is one of the first metrics that fertility specialists measure to try to determine the cause of infertility in a couple. But beyond that truism, the science of sperm count is surprisingly slippery.

For starters, no one knows what an “optimal” sperm count is. The World Health Organization sets a range of “normal” sperm count as from 15 to 250 million sperm per milliliter. (Men produce about 2 to 5 milliliters per ejaculation.) But it isn’t clear that more is better. Above a certain threshold — 40 million per milliliter, according to the W.H.O. — a higher sperm count does not mean a man is more fertile.

“Doubling your sperm count from 25 to 50 million doesn’t double your chances,” said Allan Pacey, an andrologist at the University of Sheffield and the editor of Human Fertility. “Doubling it from 100 to 200 million doesn’t double your chances — in fact it flattens off, if anything. So this relationship between sperm count and fertility is weak.”

Frozen sperm samples in the Cryos International Sperm Bank in Aarhus, Denmark. Although the male-fertility crisis is overstated, scientists say, the science of men’s health has long been neglected. 
Frozen sperm samples in the Cryos International Sperm Bank in Aarhus, Denmark. Although the male-fertility crisis is overstated, scientists say, the science of men’s health has long been neglected. Thomas Fredberg/Science Source

Germaine M. Buck Louis, a reproductive epidemiologist at George Mason University who studies environmental influences on human fertility, agreed that sperm count is a poor indicator of fertility. “We don’t see it predicting much of anything, especially in the context of a partner with a healthy female pelvis,” said Dr. Buck Louis, who was not involved in the sperm-count studies.

The authors of the 2017 study inferred that lower sperm counts equated to lower fertility — even though the sperm-count declines they documented all took place within the “normal” range, Dr. Richardson noted. “It’s similar to the whole conversation around testosterone — more is better, and more is manlier,” she said. “That’s really a point we make, that there is no known normal or baseline for average population sperm counts.”

Sperm count has other limitations as a metric. It takes around two months for stem cells in the testes to develop into new sperm, meaning that any single count is merely a snapshot of an evolving landscape.

“Something that’s going on in a man’s body one month may be totally different from what’s happening the next month, and the effects on sperm count might be changing also,” said Meredith Reiches, an author on the 2021 paper and a biological anthropologist at the University of Massachusetts, Boston

It also overlooks a vital piece of the infertility puzzle: women. Focusing only on the male metric leaves out key interactions between sperm, the female reproductive tract and the egg. “It’s very important, actually, to look at the couple,” said Dr. Bradley D. Anawalt, a reproductive endocrinologist at the University of Washington School of Medicine.

In her book, Dr. Swan suggests that sperm counts have plummeted largely due to the rise of endocrine disruptors, a class of hormone-mimicking chemicals found in everything from shampoo to TV-dinner packaging. (She also cites lifestyle factors like obesity, alcohol, and smoking.) Dr. Swan has shown in previous studies that exposure to these chemicals in utero can alter male and female sexual development.

Dr. Richardson and her co-authors suggested an alternative explanation: Perhaps sperm levels naturally rise and fall over time and within populations. The question has not been explored by reproductive researchers and cannot be answered easily, as global sperm counts before 1970 are largely unknown.

There are other possible explanations, as well. Sperm-counting is a tricky business and notoriously prone to human error, Dr. Pacey said. (“I say it from the point of view of someone who spent 30 years counting sperm and knows how difficult it is,” he added.) In a 2013 review article, he noted that as methodologies for counting had improved and been standardized since the 1980s, sperm counts had appeared to fall. In other words, it may simply be that earlier scientists were overcounting sperm.

Dr. Swan and Dr. Levine agreed that exploring these alternative hypotheses was important, so that threats to reproductive health could be established and prevented. “We showed evidence for decline, and raised alarm,” Dr. Levine wrote in an email. “We need to study the causes, including the unlikely possibility of non-pathological decline.”

There was one point that every author agreed on: Men’s reproductive health matters. And until now, it has been surprisingly neglected.

Male infertility contributes to at least half of all cases of infertility worldwide. Yet historically, women have shouldered most of the blame for the inability to conceive. And with the rise of reproductive technologies like in vitro fertilization, women’s bodies are the ones that have been meticulously measured and tracked by reproductive medicine.

As a result, science still lacks basic knowledge when it comes to sperm, said Rene Almeling, a sociologist of medicine and author of “GUYnecology: The Missing Science of Men’s Reproductive Health.” For instance, just this year, researchers reported for the first time that sperm swim in a corkscrew motion, rather than undulating like eels.

“We have built up such a medical infrastructure around the fertility and reproductivity of women’s bodies that we haven’t asked some of the basic questions about men’s reproductive health,” Dr. Almeling said. “There is just so, so much basic research still to be done about sperm.”

The main qualities of sperm that infertility specialists look at nowadays — how many, what shape and how they swim — have not changed in the past 40 years, said Dr. Abraham Morgentaler, a urologist and founder of Men’s Health Boston.

Dr. Morgentaler, who worked at a semen analysis lab at Beth Israel Deaconess Medical Center in the 1980s, attributes this stagnation to the rise of I.V.F. and other reproductive technologies, which have become frontline treatments for almost any male factor fertility problem. “It almost doesn’t even matter what’s wrong with the sperm,” he said.

These knowledge gaps radiate out to all bodies. In fact, Dr. Swan said part of her motivation for writing the book was that she wanted to see the public — men and women — become more proactive about their reproductive health.

“It’s invisible,” she said. “People don’t talk about it. You talk about, ‘Oh, I’ve got a high cholesterol measure,’ or ‘My blood pressure’s up.’ But you never would say, ‘My egg count is down,’ or ‘My sperm count is down.’”

Dr. Richardson agreed that the impact of reproductive toxins on fertility deserved further investigation. “To say that we think these are alarmist and apocalyptic claims, and they’re not well founded, is not to say that we think it isn’t an important research agenda,” she said. “There is a need to center on men’s reproductive health and understand their bodies as reproductive and as porous to the environment as anyone’s bodies.”