Half the Man His Father Was?

Charlotte Brody

Studies are showing dramatic drops in sperm counts and rising rates of reproductive health problems for men throughout industrialized countries. Are environmental contaminants partially to blame?

Studies are showing dramatic drops in sperm counts and rising rates of male reproductive health problems for men throughout industrialized countries. Are environmental contaminants partially to blame?

To answer that question, we have to start with another: what actually makes a man a man? We all learn in science class that a person’s biological sex starts with genes. The mother’s egg carries an X chromosome. If the father’s sperm carries a Y chromosome, the resulting embryo will be a boy. If the sperm carries an X, it will be a girl. Together, mother and father sex chromosomes form an embryo, either XY (boy) or XX (girl).

But gender is more complicated than genes. After sperm and egg become acquainted, the embryo’s reproductive tissues begin to develop. For about five weeks this process is identical in both males and females. Then, if the embryo is male, certain cells begin to grow and release testosterone, initiating development of the entire male reproductive system – including the prostate gland, penis, urethra and scrotum. At this time the brain is wired to set the stage for further maturation during puberty, and in the last two months of fetal development, testosterone signals the testes to descend into the scrotum.

Testosterone-induced development continues in boys throughout the first few years of life. Then things get quiet for a while until puberty, when the hormone raging begins again. It’s hard to imagine how just a handful of hormones — testosterone, estrogen, thyroid and a few other natural chemicals produced inside the body — orchestrate, through a complex and delicate balance of hormone signaling, the growth and development of all tissues and organs, including the reproductive system. It is even harder to grasp how significant changes in development and health can come from absolutely infinitesimal amounts of these natural chemicals.

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So when tiny amounts of hormonally active synthetic chemicals get into our bodies from the food we eat, the air we breathe, the water we drink and the products we use every day, they too can cause major health impacts, even at very low doses. They can disrupt the sensitive hormone balance by blocking natural messages or sending their own misleading signals that fool the body into doing the wrong thing at the wrong time.

Thousands of peer-reviewed, published studies (mostly animal studies) suggest that certain human reproductive health problems are tied to synthetic or industrial chemical exposures. In males, these problems include two common birth defects: cryptochordism (undescended testicles) and hypospadias (a deformity of the penis), both of which have also been linked to low sperm counts and testicular cancer later in life. All four of these conditions, collectively called testicular dysgenesis syndrome (TDS), can arise from the same origin – disrupted hormone signaling in the womb during critical stages of male reproductive system development.

Animal studies have demonstrated time and time again that prenatal exposures to chemicals – including vinclozolin (a widely used fungicide), phthalates (found in PVC plastic and personal care products), bisphenol A (found in polycarbonate bottles and the linings of canned foods and beverages), and the banned but still present industrial chemicals DDT and PCBs – can cause TDS.

Statistical analysis shows that TDS conditions are on the rise in humans, particularly the incidence of low sperm counts in most highly developed countries. In several industrial regions, sperm counts have dropped fifty percent over the last 50 years, and several new studies suggest that testosterone levels may have declined 1% per year for the past 40-50 years. In the United States alone, testicular cancer has dramatically increased since the 1970s, with a reported 60% increase among whites and Asians, and 40% increase in blacks.

So what can men and their families do, to protect their ability to become fathers, and increase their chances of living a long and healthy life? Green purchasing helps. Buying products that are free of phthalates, pesticides, bisphenol A and other chemicals gives us a way to protect ourselves and contributes to the broader effort to shift markets and move the economy in a healthy direction. Many resources exist that can help guide families, communities, and institutions to greener products.

Green policies help even more. A few cities, several states and the federal government are all currently considering bills that would restrict the use of phthalates, bisphenol A and other environmental contaminants; put research dollars into green solutions; and require companies to prove that chemicals are safe before they are put into products and released on the market. Those bills and the elected officials that support them deserve our support. Chemical and product manufacturers continue to argue that animal studies should not be used to determine human health policies, but the U.S. Food and Drug Administration (FDA), tasked with protecting public health by regulating food and drugs, routinely relies on animal studies to decide which chemicals are too dangerous to be used as pharmaceuticals. Why shouldn’t they do the same for the wide variety of other chemicals that impact our health?

Most importantly, we need to give our fathers, our sons and ourselves a greener future. That can happen once we come to collectively understand how our families’ health is connected to the health of everything and everyone else. Anything we can do to reduce harm and prevent unnecessary chemical exposures will protect the health of all men and future generations to come. What better gift could a father ask for?

Learn More!

A new report, “Shaping Our Legacy: Reproductive Health and the Environment,” will be available in the coming weeks at here. The report comprehensively outlines the science behind environmental influences to male reproductive health, and points the reader to many available resources for what you can do.

Check out the Collaborative on Health and the Environment website, and the Commonweal website.

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Roundups Sexual Health

This Week in Sex: A Reason to Celebrate on Tax Day?

Martha Kempner

Same-sex married couples get a long-awaited policy change (but maybe not a tax break), there’s encouraging news about the development of a male contraceptive method, and the month of April brings some much-needed attention to sexually transmitted diseases.

This Week in Sex is a summary of news and research related to sexual behavior, sexuality education, contraception, STIs, and more.

Tax Day 2016: A Reason to Celebrate for Same-Sex Couples

Many in the United States dread this time of year because it means dealing with the Internal Revenue Service (IRS). But there is something to celebrate this time around: 2016 is the first year that every married same-sex couple can file both federal and state taxes together.

After the U.S. Supreme Court ruling striking down part of the Defense of Marriage Act in 2013, the IRS changed its rules to allow legally married same-sex couples to be treated as married for federal tax purposes. While this was a step forward for equality, it actually made tax filing far more complicated for some couples, as NPR explains. Those who lived in a state where same-sex marriage was not recognized would have to file federal taxes as a married couple, but state taxes as individuals. To make matters trickier, state taxes are often based on your federal tax return; some couples had to create mock individual federal returns just to figure out what they owed their state.

This all changed in June 2015, when the Supreme Court ruled in Obergefell v. Hodges that no state can prevent same-sex couples from marrying and all must recognize their unions, effectively legalizing marriage equality nationwide. So this makes Tax Day 2016 the first day that all married couples—regardless of gender—will be treated equally.

While many are celebrating the symbolic victory, some couples may be shocked to find out that they actually owe more taxes as a married couple.

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Another Step Toward Male Contraception

Over the last few decades, researchers have developed numerous ways to prevent pregnancy, from hormonal pills that block ovulation to IUDs that slow the movement of sperm through the reproductive tract. Up until now, male contraception has been limited to one barrier method, condoms, and one permanent one, vasectomies. Now, a new study lends some proof of concept for possible reversible male contraception methods.

As Rewire has reported, one method in development, known as Vasalgel, is intended to be injected into the vas deferens and create a physical barrier preventing sperm from leaving the testicles. Scientists behind Vasalgel say they intend for it to be reversible with another injection. This could be on the market as soon as 2018. But scientists are still looking for other ways to temporarily render males infertile—possibly ones that do not involve an injection into the testicles.

A new study suggests new chances for one such method. University of Virginia researchers are focused on an enzyme known as TSSK2, which helps make sperm motile. They think this enzyme could be the key to a contraceptive method because it is only found in the testicles and only involved in the very last state of sperm production. In theory, this means that blocking this enzyme could produce nonswimming sperm without causing side effects in the rest of the body. They have found a way to mass produce this enzyme in a laboratory, and their next step is to test existing drugs to see if any can bond only to TSSK2 in the testicles without affecting the rest of the body.

Clearly, they are years away from an actual male birth control pill based on this concept. But this is not the only idea for a male birth control pill under development. As Rewire reported last year, other scientists are working with existing drugs to block a protein called calcineurin and have successfully rendered mice infertile by doing so.

While men wait—though it’s still unclear if many are really interested in their own pill—we should all remember that between condoms, pills, patches, rings, and IUDs, there are many methods couple can rely on for preventing pregnancy.

April is STD Awareness Month

With so many months and even weeks dedicated to disease, causes, or remembrances, it can be easy to let them pass unrecognized. But we here at Rewire thought it was important to remind our readers that April is STD Awareness Month, because the epidemic in this country is growing out of control. For the first time in a decade, cases of chlamydia, gonorrhea, and syphilis are all on the rise.

Syphilis—a disease that not long ago, we thought could be eradicated—has increased by 40 percent between 2010 and 2014. While much of this increase is seen in men who have sex with men, rates among women are increasing as well. There has also been an increase in cases of ocular syphilis, which infects the eyes and can cause permanent blindness.

Along with this, we have seen a rise in the rate of congenital syphilis, which occurs when an infected woman passes the bacteria to her infant. As Rewire reported, the rate of congenital syphilis increased 38 percent between 2012 and 2014. Congenital syphilis can cause miscarriage, stillbirth, severe illness in the infant, and even early infant death. There were 438 nationwide cases of congenital syphilis in 2014, which led to 25 stillbirths and eight deaths within 30 days of birth.

Rewire has also been reporting on the possibility of antibiotic-resistant strains of gonorrhea that could turn a once easy-to-treat bacterial infection into a very dangerous disease.

We really do need to be aware of STDs and take steps to prevent them in ourselves and our communities. The CDC has given us all three easy tasks for this month—Talk, Test, Treat. So, for April, let’s talk openly about STDs with our friends, relatives, and partners; get tested if we’ve been exposed to any risk; and of course, seek treatment if necessary.

Roundups Sexual Health

This Week in Sex: News From the HIV Epidemic

Martha Kempner

This week in sex: Scientists report the first case of HIV transmission to a patient adhering to PrEP protocols, two studies show a new vaginal ring can help women prevent HIV, and young people still aren't getting tested for the virus.

This Week in Sex is a weekly summary of news and research related to sexual behavior, sexuality education, contraception, STIs, and more.

With the death of Nancy Reagan, the 1980s AIDS crisis is back in the national spotlight. But, of course, HIV and AIDS are still ongoing problems that affect millions of people. This week in sex, we review scientists reporting the first case of HIV transmission to a patient adhering to PrEP protocols, two studies showing a new vaginal ring can help women prevent HIV, and evidence that young people still aren’t getting tested for the virus.

First Case of HIV Transmission While on Truvada

Last week, Canadian scientists reported on what they believe to be the first HIV infection in a patient who was following a PreP (Pre-Exposure Prophylaxis) regimen.

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PrEP is a method of HIV prevention. By taking a daily pill that contains two HIV medicines, sold under the name Truvada, individuals who are HIV-negative but considered to be at high risk of contracting the virus can prevent infection. Studies have found that PrEP is very effective—the Centers for Disease Control and Prevention estimates that people who take the medication every day can reduce their risk of infection by more than 90 percent from sex and by more than 70 percent from injection drug use. One study of men taking PrEP found no infections over a two-and-a-half-year period.

PrEP is less effective when not taken regularly, but the new case of reported PrEP failure involves a 43-year-old man who said that he took his medication daily. His pharmacy records back up that assertion. The man’s partner has HIV, but is on a drug regimen and has an undetectable viral load. The man did report other sexual encounters without condoms with casual partners in the weeks leading up to his diagnosis.

Dr. David Knox, the lead author of this case study, notes that it is difficult to know if a patient really did adhere to the drug regimen, but the evidence in this case suggests that he did. He concluded, “Failure of PrEP in this case was likely due to the transmission of a PrEP-resistant, multi-class resistant strain of HIV 1.”

Experts say, however, that they never expected PrEP to be infallible. As Richard Harrigan of the British Columbia Center for Excellence in HIV/AIDS told Pink News, “I certainly don’t think that this is a situation which calls for panic …. It is an example that demonstrates that PrEP can sometimes be ineffective in the face of drug resistant virus, in the same way that treatment itself can sometimes be ineffective in the face of drug resistant virus.”

Still, some fear that the new study will add to the ongoing debate and apathy that seem to surround PrEP. While some experts see it as a must-have prevention tool, others worry that it will encourage men who have sex with men to forgo using condoms and perhaps increase their risk for other sexually transmitted infections. Still, only 30,000 people in the United States are taking the drug—an estimated one-twentieth of those who could benefit from it.

A New Vaginal Ring Could Help Women Prevent HIV Infection

Researchers have announced promising results from two studies looking at new technology that could help women prevent HIV. The dapivirine ring, named after the drug it contains, was developed by the International Partnership for Microbicides. It looks like the contraceptive ring, Nuvaring, and is similarly inserted high up into the vagina for a month at a time. Instead of releasing hormones to prevent ovulation, however, this ring releases an antiretroviral drug to prevent HIV from reproducing in healthy cells. (A ring that could prevent both pregnancy and HIV is being developed.)

The two studies of the ring are being conducted in Africa. One study recruited about 2,600 women in Malawi, South Africa, Uganda, and Zimbabwe. It found that the ring reduced HIV infection by 27 percent overall and 61 percent for women over age 25. The other study, which is still underway, involves just under 2,000 women in seven sites in South Africa and Uganda. Early results suggest that the ring reduced infection by 31 percent overall when compared to the placebo.

Both studies found that the ring provided little protection to women ages 18-to-21. Researchers are now working to determine how adherence and other biological factors may have impacted such an outcome.

Young People Not Getting Tested for HIV

A study in the February issue of Pediatrics found that HIV testing rates among young people have not increased in the last decade. The researchers looked at data from the Youth Risk Behavior Survey (YRBS), which asks current high school students about sexual behaviors in addition to questions about drugs and alcohol, violence, nutrition, and personal safety (such as using bike helmets and seat belts). Specifically, the YRBS asks students if they’ve ever been tested for HIV.

Using YRBS data collected between 2005 and 2013, the researchers estimated that 22 percent of teens who had ever had sex had been tested for HIV. The percent who had received HIV tests was higher (34 percent) among those who reported four or more lifetime partners. Overall, male teens (17 percent) were less likely than their female peers (27 percent) to have been tested.

Researchers also looked at data from the Behavioral Risk Factor Surveillance System, which asks similar questions to young adults ages 18 to 24. Among people in this age group, between the years of 2011 to 2013, an average of 33 percent had ever been tested. This review of data also found that the percentage of young women who get tested for HIV has been decreasing in recent years—from 42.4 percent in 2011 to 39.5 percent in 2013.

The authors simply conclude, “HIV testing programs do not appear to be successfully reaching high school students and young adults.” They go on to suggest, “Multipronged testing strategies, including provider education, system-level interventions in clinical settings, adolescent-friendly testing services, and sexual health education will likely be needed to increase testing and reduce the percentage of adolescents and young adults living with HIV infection.”


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