Mr. Patriot, Science can still determine with precision whether the child is male or female in spite of such anomalies, and I quote "The infants who have ambiguous genitals are examined carefully to determine their actual sex. Often blood tests are necessary. Since males have XY pattern and females have XX pattern of chromosomes, the blood test to determine the chromosomal make-up correctly detects the sex of the infants."
Neonatal Genital Defects (Male And Female Defects) - You Ask MD Answers
The author you are quoting is oversimplifying the biology of sex, in a couple of ways. First: it's not always true that a person will have entirely either XY or XX chromosomes. Some intersex people are both with a mix of both, i.e. some cells contain XX and others XY. Some people are born with an extra sex chromosome. Those conditions are rare,
but not unheard of.
Secondly, the biology of sex involves more than just chromosomes. There is in general a complicated relationship between genetics and phenotype, where gene expression depends on environmental conditions in a great many complicated ways. A lot of sexual development depends on various hormones, and hormone levels in early development rely on more than just X and Y chromosomes. That's how you end up with ambiguity in genitalia, but there's also some evidence of brain differences between people
who identify as transgender and those who do not.
"Male and female brains are, on average, slightly different in structure, although there is tremendous individual variability. Several studies have looked for signs that transgender people have brains more similar to their experienced gender. Spanish investigators—led by psychobiologist Antonio Guillamon of the National Distance Education University in Madrid and neuropsychologist Carme Junqu Plaja of the University of Barcelona—used MRI to examine the brains of 24 female-to-males and 18 male-to-females—both before and after treatment with cross-sex hormones. Their results, published in 2013, showed that even before treatment the brain structures of the trans people were more similar in some respects to the brains of their experienced gender than those of their natal gender. For example, the female-to-male subjects had relatively thin subcortical areas (these areas tend to be thinner in men than in women). Male-to-female subjects tended to have thinner cortical regions in the right hemisphere, which is characteristic of a female brain. (Such differences became more pronounced after treatment.)"
Obviously the topic is complicated. It's not really surprising that medical doctors (who may not be specialists in this area), speaking to clients who tend to expect their children to either be male or female, will try to provide them with answers that fit their expectations. And it's true that biologically humans are
nearly sexually dimorphic. A large majority of people are unambiguously male or female, and do not experience any gender dysphoria. Just like a large majority of people are heterosexual. So it's understandable that
gender categories (social norms, values, expectations tied to biological sex) tend towards being dichotomous. But the absoluteness with which some people treat those categories does not exist neatly in the underlying biology. Maybe only 1-5% of people will have any intersex traits, and some of those traits (like the brain differences) will not be readily apparent. The biology is not even well understood yet. But that 1-5% of people do exist.
My view is that it's understandable that we make
gender as a social category -- distinct from biological sex but based in it -- an absolute, admitting only male and female. Although other cultures exist which do not do this (cf. Hijras in India and Pakistan). But it's something like a reasonable first-order approximation of the underlying biology. The whole "50 genders" thing is mostly a straw-man; very few people even on the left hold such a view. But the flaw with that idea is that it mistakes
social construction for
individual construction. It misunderstands the sociology of gender. Society collectively determines what categories are legitimate (in large part based on the above approximate dimorphism), and individuals don't really have the power to confer legitimacy on their own unique understanding of themselves.
But, that in itself explains the conundrum that transgender people find themselves in. Imagine that you experience extreme gender dysphoria from a young age -- a phenomena that very likely is rooted in some biologically intersex characteristics. What can you do? Your socialization tells you very strongly that you must either be male or female. Those are the legitimate options. So you try to adapt yourself to fit one of them, because it's very hard to develop a normal and positive self-image if you can't see yourself as belonging to a legitimate category. But clearly trying to accommodate transgender people simply by treating them as members of their self-identified sex is also culturally problematic, as evidenced by the uproar over bathrooms and locker-rooms. It seems to me that recognizing that sexual dimorphism is not absolute is the first step towards resolving the dilemma. You can't actually define transgender people out of existence. If social pressure were enough, there would already be no transgender people, just as there would be no gay people if social stigma were enough to discourage it. Maybe it doesn't always make sense to always see an MtF transgender person as being identical to a cisgender female person, whether biologically or in terms of their experience of the world. Recognizing that sexual dimorphism is only
nearly dimorphic, rather than being absolutely dimorphic, might allow us to come up with better ways, as a culture, to accommodate the existence of transgender people, by allowing us to recognize that our gender categories are also not absolute.