Gender Bending EDCs

As the wise biologist and sex researcher Alfred C. Kinsey once said in 1948, "The living world is a continuum in each and every one of its aspects. The sooner we learn this concerning human sexual behavior, the sooner we shall reach a sound understanding of the realities of sex." These words still hold true today as we navigate the complexities of human sexuality.

When it comes to scientific questions about gender identity and sexual orientation, the answers are far from simple. The interplay of genetic and environmental factors makes these inquiries both complex and intriguing. In therapy, it's often observed that individuals who identify as gay often wonder about the reasons behind their sexual orientation, while heterosexual individuals rarely seek such explanations.

The existence of a "gay gene" has been a topic of heated debate for years. However, as Siddhartha Mukherjee, MD, explains in his book The Gene: An Intimate History, the reality is not as straightforward as a single gene determining one's sexual orientation. Geneticists have discovered specific locations on chromosomes associated with same-sex attraction, but it's not necessarily a single gene. It could be a stretch of DNA that regulates a nearby gene or even influences a gene located far away. The intricacies of genetic influences on sexual orientation are still being unraveled, but there's no denying that genetics play a role.

In 2011, Lady Gaga's empowering song "Born This Way" became a powerful anthem for LGBTQ rights and acceptance. However, the concept of being "born this way" doesn't fully encompass the experiences of individuals whose sexuality and/or gender are fluid. This diverse population is continuously expanding. According to a 2017 Gallup poll of over 340,000 adults in the United States, there has been a significant increase in the percentage of individuals identifying as LGBT, primarily driven by millennials born between 1980 and 1999. In 2017, 8.1 percent of this group identified as LGBT, compared to 5.8 percent in 2012.

It's becoming increasingly recognized that sexuality exists on a spectrum, with many individuals not exclusively attracted to one gender or the other. Similarly, gender is also a complex and nuanced concept. It's important to differentiate between gender and sex, as they are not the same, although they are often mistakenly interchanged. Sex is determined by biology, including chromosomes, hormones, and reproductive organs at birth. On the other hand, gender is deeply rooted in one's inner sense of self, encompassing feelings, behaviors, and attitudes.

The notion of a gender continuum, which suggests variations between the traditional categories of male and female, has gained acceptance. However, some experts challenge this concept, as it fails to account for the vast array of possibilities in establishing one's personal gender. Diane Ehrensaft, PhD, author of "Gender Born, Gender Made," prefers the term "gender web," emphasizing the intricate pathways that individuals navigate in three dimensions.

For some transgender individuals, gender identity may not align consistently. As Jacob Tobia, a gender-nonconforming writer, shares in their memoir, "Sissy: A Coming of Gender Story," their gender was not a fixed aspect of their identity. Tobia beautifully describes their gender as an onion with multiple layers but no distinct core.

Gender fluidity generally refers to a blending or mixture of cultural notions of masculinity and femininity. The degree of fluidity varies from person to person. Some individuals experience shifts in their gender over the course of their lives, while for others, it can change more frequently, even daily or hourly. The triggers for these changes remain unclear—whether they are biological, psychological, environmental, or a combination thereof.

While it seems that more people are identifying as gender fluid, it's uncertain whether this is an actual increase or simply a result of greater recognition and acceptance of this construct. Nevertheless, individuals grappling with gender identity face unique challenges. Gender dysphoria, a condition where one's emotional and psychological identity does not align with their assigned biological sex, can cause significant distress. This dysphoria can manifest in early childhood or arise during puberty when the body undergoes significant changes.

It's crucial to differentiate gender identity from sexual orientation, as they are distinct aspects of a person's identity. Gender identity can change without affecting sexual attraction, while for others, both gender identity and sexual attraction may fluctuate. Additionally, those who identify as binary—either male or female—can have consistent attraction to the opposite or same sex, or even be attracted to both sexes (bisexual). Gender identity and sexual orientation can be mix-and-match propositions, with a wide range of possibilities that can evolve over time.

The terminology used to describe gender is vast and ever-evolving. The lexicon surrounding gender identity continues to expand as our understanding deepens.

While I'm not an expert in this particular field, I do possess expertise in how environmental influences impact sexual and reproductive development. Therefore, I can provide insights into that aspect.

Scientists and mental health experts have been exploring various questions regarding gender identity issues. They are particularly interested in understanding the influence of changing social attitudes, greater acceptance of individuals' true selves, and the potential role of biological factors. Another intriguing question that has arisen is whether environmental chemicals could be impacting human sexuality and gender identity development.

In a thought-provoking Psychology Today article from 2019, Dr. Robert Hedaya, a clinical professor of psychiatry at Georgetown University School of Medicine, highlighted the influence of endocrine disrupting chemicals (EDCs) as a potential cause for the blurred lines in understanding human gender. This perspective has also intrigued many other clinicians and researchers, but it remains a difficult topic to address openly. One theory proposes that exposure to EDCs, particularly phthalates, during prenatal development may affect a fetus's testosterone levels, potentially contributing to gender dysphoria. Notably, these same chemicals have been associated with an increased risk of autism spectrum disorders (ASDs) in males, and there is a higher occurrence of ASD and gender dysphoria together than expected.

Another hypothesis suggests that EDCs could interfere with complex biochemical pathways in the brain, influencing an individual's association with their assigned sex at birth or their gender expression through behavior. Either of these effects could lead to gender dysphoria.

Recent research has also shed light on the impact of acetaminophen (Tylenol) on gender-related brain development. The default brain during development is female, so when an expectant mother is exposed to antiandrogenic chemicals (those that lower testosterone) during pregnancy, her male baby may have a slightly less "male-typical" brain and exhibit behavior more commonly associated with females. Studies have shown that exposure to hormone-mimicking chemicals during pregnancy can diminish some of the typical gender differences observed in brain development between boys and girls. For instance, boys usually exhibit more language delays than girls by thirty months of age, but when expectant mothers have low exposure to antiandrogenic phthalates or avoid using Tylenol during pregnancy, the gender difference in language delay becomes more pronounced. This suggests that these chemical exposures can blur the distinctions between genders in various aspects of development.

Understanding the impact of EDCs on gender identity is challenging. Animal studies cannot provide conclusive evidence since changes in sexual behavior or biology in animals do not directly reflect gender identity, which requires self-awareness. Humans, being self-aware beings, present a different scenario. However, it is nearly impossible and ethically problematic to conduct controlled clinical trials where identical twins, with almost identical genetic profiles, are intentionally exposed to high levels of EDCs during their formative years to observe potential effects on their sexuality and gender identity. Even if such a study were feasible, it may not yield informative results if the critical period for the development of sexuality and gender identity occurs during pregnancy, when the genitals and brain undergo significant development.

Furthermore, determining the appropriate endpoints to measure and at what ages is challenging. Should it focus on brain function, social behavior, self-concept, or other factors? Surveys often rely on binary definitions of gender (male or female), but gender identity is a deeply personal and individual experience.

To address these complexities, some researchers advocate for the use of scales that assess gradations of femininity and masculinity to capture individuals' gender identification. Stanford University researchers conducted a national survey involving over fifteen hundred adults, asking them to rate their gender identification based on self-perception and others' perception. Surprisingly, fewer than one-third of respondents rated themselves at the highest level of their assigned sex's typical identification scale. Moreover, 76 percent of respondents reported overlapping characteristics of femininity and masculinity in their gender profiles. The open-ended feedback provided by respondents revealed that they considered various factors, including appearance, and personality.

The question of what defines someone as male or female, beyond the basic anatomical differences, remains unresolved even from a biological standpoint. Is it determined by the presence or absence of specific reproductive organs? Or does it relate to secondary sex characteristics like a deeper voice, increased hair, or greater muscle mass? Perhaps it hinges on the balance of estrogen and testosterone in an individual's body. While estrogen is generally associated with females and testosterone with males, both sexes possess these hormones, albeit in varying proportions. If a woman's body produces higher levels of testosterone than the average female due to a genetic anomaly or heightened sensitivity to the hormone, she may develop male secondary sex characteristics such as increased muscle mass, facial and body hair, or even an enlarged clitoris.

This ongoing debate has particularly troubled the realm of elite sports. Some women who excel as competitive athletes naturally possess higher testosterone levels and greater muscle mass than the average woman, just as some men have higher levels than others. In response, sports authorities have often resorted to gender-verification testing. The chromosome test, introduced by the International Olympic Committee in 1968, involved taking cells from an athlete's mouth using a cheek swab and testing for the XX chromosome pattern typically found in females. The chromosome test was considered a significant improvement over previous verification practices that subjected female athletes to naked parades before a panel of physicians, mandatory genital checks, or invasive physical examinations.

These tests have always been controversial, with geneticists and endocrinologists criticizing the chromosome test for oversimplifying the complex interplay of genetic, hormonal, and physiological factors that determine an individual's sex. It is worth noting that men have never been subjected to similar measures to prove or verify their masculinity. Nevertheless, the crucial point is that significant variation exists among both men and women concerning their anatomy, hormone levels, body composition, and other physiological factors. Thus, one underlying concern with athletic decisions is whether banning women with naturally elevated testosterone levels from competing in women's events creates a slippery slope that may lead to prohibiting athletes with other physiological anomalies.

This issue is incredibly intricate, involving not only questions of gender identity but also human rights, privacy, and the right of individuals to compete based on their innate characteristics. After all, elite athletes possess natural, and possibly genetic, attributes that give them a competitive advantage. Consider the exceptional long legs of Jamaican sprinter Usain Bolt, an eight-time Olympic gold medalist, or the remarkable wingspan (eighty inches from fingertip to fingertip) of competitive swimmer Michael Phelps, the most successful Olympian in history with twenty-eight medals. Should individuals like them be disqualified from competition due to their biological advantages? Should men be excluded from events based on their testosterone levels, whether unusually high or low? Determining where to draw the gender boundaries in competitive sports is undeniably challenging.

The development of a person's gender identity typically occurs in early childhood, usually by the age of three, although their ability to label and comprehend gender differences may not emerge until around eighteen to twenty-four months. Research suggests that babies can differentiate between male and female in their first year of life. Concrete associations between gender and physical appearances or activities start to form during this period. A real-life example illustrates this process. Tracy's son, Aiden, at the age of three, requested a baby brother. When baby Barry arrived, Aiden's wish appeared to come true. However, before Barry's third birthday, he developed an affinity for wearing his mother's clothes, a fascination with the color pink, and a preference for dolls over traditional boy toys. Barry declared to Tracy, "I'm a girl like Mommy!" He became anxious about his anatomy and even questioned his mother about the absence of a penis. Tracy, a thirty-four-year-old graphic designer, embraced Barry's desires and began referring to Barry as "she," while still retaining the original name. Even Aiden introduced Barry as his sister. Tracy noticed a remarkable transformation in Barry, who exhibited changes in speech, posture, and behavior when wearing girl's clothing. Barry became happier, more expressive, and shed social reservations. Barry, now four years old, attends preschool, enjoys playing with friends, and partakes in tea parties. Tracy and her family wholeheartedly accept Barry, but she acknowledges the challenges her child may face in a world that may not be as accepting.

In contrast to individuals like Barry, clinicians have recently observed a phenomenon known as rapid-onset gender dysphoria (ROGD) in teenagers, where gender dysphoria emerges suddenly or rapidly during or after puberty. Social media has played a significant role in providing support and connection for teenagers grappling with gender identity or gender dysphoria. However, concerns have been raised about the potential negative impact of online influences, suggesting that some individuals may be influenced to experience dysphoria through social contagion.

A controversial 2018 online survey invited parents who believed their children displayed signs of rapid-onset gender dysphoria to share their observations by answering ninety questions. The survey included 256 parents recruited from three websites. Among the participants, 83 percent of the children were assigned female at birth, 41 percent had identified as nonheterosexual before identifying as a different gender, and 63 percent had been diagnosed with a mental health or neurodevelopmental condition before the recognition of their gender dysphoria. However, criticism has been directed towards the methodology of this study, as it relied on parents' perspectives rather than the experiences of the children themselves. Furthermore, concerns have been raised about the potential influence of social contagion on these reported cases. Some experts argue that multiple factors, including mental health conditions, traumatic experiences, and family stressors, contribute to the development of gender dysphoria. However, this pathologizing framework has drawn criticism from transgender activists, who believe it further stigmatizes gender-nonconforming youth.

Another aspect to consider is the phenomenon of desistance, where some prepubescent children who initially present as transgender may no longer experience gender dysphoria in adolescence and may identify as cisgender. The term "desistance" is loaded because it carries associations with the cessation of offensive or antisocial behavior in the field of criminology. The persistence of a transgender identity is often higher among individuals who undergo hormone treatment and social transition. It is unclear whether this is because these actions allow individuals to express their authentic selves or because they feel compelled to conform to a binary identity.

Ben's journey to self-discovery regarding his gender identity was a long and complex one. Feeling different from a young age, Ben struggled to fit in and engaged in activities that defied traditional gender norms. After failed attempts at pregnancy and a series of relationships, Ben sought therapy to explore his gender identity. Hormonal treatments, such as taking testosterone, played a significant role in Ben's realization that he was transgender. Undergoing surgery to remove his breasts and uterus, Ben found peace and happiness in his identity as a gay man. He now works as a counselor and educator in New York City and reflects on his journey with gratitude and contentment.

Defining gender and sexuality is undoubtedly a complex challenge, encompassing various nuances and aspects, including physical ones. Recent research suggests that, alongside fish, frogs, and reptiles, an increasing number of children are being born with intersex variations, including ambiguous genitalia. The term "hermaphrodite" is considered demeaning, which led to the introduction of the term "intersex" as a replacement. More recently, "disorders of sex development" (DSD) has become the preferred medical term.

However, obtaining reliable statistics on the prevalence of intersex variations is challenging due to disagreements among researchers regarding the definition of intersex in human beings. Generally, the term is used to describe a range of conditions where individuals are born with reproductive or sexual anatomy that does not conform to the typical definitions of male or female. Yet, these anomalies can involve abnormalities of the external genitals, internal reproductive organs, a mismatch between external genitals and internal reproductive organs, sex-chromosome abnormalities, or other uncommon conditions.

For instance, individuals born with genitals that fall between typical male and female anatomy, such as an unusually large clitoris or the absence of a vaginal opening in someone assigned female at birth, or a very small penis or divided scrotum resembling labia in someone assigned male at birth, could be considered intersex. The category also includes individuals who appear female externally but have primarily male anatomy internally, as well as those with variations in their cells, ranging from XX chromosomes to XY chromosomes. It also encompasses individuals born with congenital adrenal hyperplasia (CAH), an inherited disorder resulting in low levels of the stress hormone cortisol and high levels of androgens (male hormones), leading to masculinization of the genitals in female infants and early puberty in both boys and girls. Some individuals may not discover their intersex anatomy until puberty or when they learn of their infertility. According to the Intersex Society of North America, some people may live and die with intersex anatomy without anyone, including themselves, ever knowing.

Defining intersex is challenging, let alone determining the prevalence of these conditions. The incidence of visibly atypical genitalia in newborns, as reported by doctors in medical centers, is estimated to be around one in fifteen hundred births. However, many other babies may have subtler variations in their sex anatomy that go undiagnosed. Experts at Children's National Health System suggest that some form of DSD affects approximately one in a hundred newborns. At this point, estimating the prevalence of these conditions remains somewhat speculative.

Nevertheless, researchers are exploring the potential influence of endocrine-disrupting chemicals (EDCs) and other environmental factors on intersex variations. Studies have found associations between high prenatal exposure to EDCs, such as occupational exposure to pesticides or phthalates, and an increased risk of external genital malformations in male newborns. Researchers at the University of North Texas have investigated the physiological pathways through which EDCs can impact sexual differentiation in humans.

Studies on animals have demonstrated that hormone exposure in utero affects sex-related physical and neural development. For example, the sexual behavior of rodents is influenced by the sex of their immediate neighbors in the womb. Female pups developing between two male pups receive small additional doses of testosterone from each neighbor, resulting in somewhat more masculine genitals and an increased likelihood of mounting other females and reduced attraction to males during sexual activity. In another study, male monkeys exposed to bisphenol A (BPA) in the womb exhibited more female-typed behaviors, such as clinging to their mothers and engaging in social exploration, after birth. Whether hormones come from chemicals or occur naturally, these changes in genital development and gender-specific behavior can occur in utero.

Regarding humans, there are still many unknowns about the potential effects of in utero chemical exposure on individuals' gender identity as they grow up. However, it is known that prenatal exposure to endocrine-disrupting chemicals appears to influence boys' play behavior. In a study, mothers were asked about their four- to seven-year-old children's play behavior using a standardized questionnaire. Boys who had higher levels of prenatal exposure to the potent chemical di-2-ethylhexyl phthalate (DEHP), which can lower fetal testosterone levels, scored significantly lower on the "masculine scale." In other words, they were more likely to play with dolls and less likely to engage with trucks and guns. Similarly, a study from the Netherlands in 2014 used the same questionnaire and found that exposure to dioxins and PCBs was associated with more feminine behavior in boys, whereas in girls, exposure to these chemicals was associated with less feminine play behavior.

Research on females born with CAH, who are exposed to high levels of androgens during their early years, has revealed that despite being raised as girls, they often exhibit behavior that is somewhat more male-typed. They are not as masculine as "typical" males but are more so than "typical" females. During free-play sessions, girls with CAH, aged two and a half to twelve, showed a greater preference for boys' toys, particularly trucks, compared to girls without CAH. They also displayed less interest in traditionally feminine toys such as dolls. Additionally, they are slightly more likely to experience gender dysphoria or identify as less female. However, it is important to note that the majority of girls with CAH still identify as girls.

So where does that leave us? Gender ideology remains a highly debated topic in popular culture. However, in our pursuit of progress and what we perceive as right, we often overlook the need for retrospection to understand how we arrived at this point. It is important to acknowledge that endocrine-disrupting chemicals (EDCs) do have an impact on gender fluidity. This raises an important question: should we normalize this dysfunction or recognize its effect on human health and work towards implementing policies and education to raise awareness about this issue globally?

It is crucial to emphasize that transgender individuals themselves are not the problem. However, it is worth considering the argument: would we find ourselves in this situation if EDCs were not present?

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