The Fetal Environment
The Embryo - Introduction
The Germ Cells
Germ Line and Somatic Mutations
Conception and Development.
The SRY Gene.
Genetic Errors of Metabolism.
The Fetal Environment.
New Babies Whose Sex is Unknown
For many years, during the period when the social learning school held centre-stage, the accepted principle was that of John Money(1) that gender identity is determined by the sex of rearing. (A principle that has always been criticised by Diamond(2) )
More recently the pendulum has swung the other way with many claiming that gender behaviour is determined in the womb, and this wholly determines gender identity.
Although this, the so-called 'nature vs nurture' debate has extreme political overtones. it will be apparent by the end of this article that the debate is more than an abstract theoretical argument. It has serious consequences for many people.
All the organs within the fetus are most at risk from influences within, or from outside the womb, at the times when they are developing most rapidly. In the case of the brain, or, more accurately, the central nervous system, this is from the third to the fifth week, with a somewhat lower vulnerability from then on. Since testosterone levels are falling, it is the beginning of the sixth week that some workers label as the sensitive period for 'masculinisation'.
Much has been made of the effect of prescribed drugs on development in the womb. Clearly, the mother's environment, whatever she eats or drinks, and her state of well-being or anxiety, affects the fetus. Also important is the intensity and duration of the effect. However, only in extreme conditions is the buffering effect of the placenta overcome sufficiently to affect development seriously. Moreover, fetuses differ in the same way as any individuals do, and may be more or less vulnerable.
The whole picture is the organism matching itself to its individual environment for the best fit. It may be that we notice gender effects because we are looking for them. It may be that our criteria of 'normal' development are too rigid.
The main debate centres on the effects of androgens and estrogens during fetal development. There is said to be a distinction between what are called the 'organising effects' where development may sensitise receptors preferentially for a particular later behaviour, and the 'activation' effect, where the hormone either triggers or facilitates the occurrence of the behaviour. For instance, testosterone, in most mammals, organises development to produce male bodily sexual characteristics. At the appropriate time, it is associated with male behaviour patterns. However its central role may have been overemphasised, producing a sort of 'cult of testosterone.' Many writers seem to have confused correlation with causation. Moreover, the actual process, and the degree of its effect, varies greatly between one species and another.
Many reports focus on Androgen Insensitivity Syndrome. The sheer quantity makes it impractical to review them all here. Some individuals develop in a feminine direction, are reared as female and are said to acquire a sense of identity as female. Others have a degree of masculinisation of the genitals, are brought up as males, and are said to be happy to be so. The variability of this syndrome is at once its interest and a demonstration of the flaws in the theory. The children's upbringing is based on judgments about their genitals, with arbitrary criteria for penis or clitoral length.
They were brought up as girls, but were much more inclined to rough-and-tumble play as they grew up. The theory is that the administration of the hormone had altered the development of their fetal brains.
These latter studies have been fiercely criticised, not least by Fausto-Sterling(3) and Bleier.(4) Among other criticisms is that the comparison was with other 'normal' boys and girls. It might well have been better to compare them with daughters of pregnancies that threatened to miscarry, but had not been prescribed hormones.
More importantly, because of their altered genitalia, their parents might have treated them differently. Particularly, if their doctor had warned of a possible effect, or a psychologist had taken an interest in the case, they might have labelled aspects of behaviour as boyish, rather than tomboyish. The child might well come to label their behaviour in the same way.
It should be noted that, though these children exhibit behaviours not considered appropriate for their gender, they are said to almost always remain in the female role. The CAH girls, in particular, are exposed to excess androgens throughout their time in the womb, yet very few choose to live out their lives as males.
The questions asked by many writers is that, although the conditions described can give valuable insight into influences on gender identity, can one draw rigid rules that then apply to people who appear to have have developed normally? What we are looking at here, in effect, is sexual dimorphism rather than gender.
Moreover, most of the conditions described, show considerable variation in effect from one individual to another. To quote specific cases, we have seen that the hermaphrodite Mr. Blackwell and many XXY people have no doubt of their gender status. The most that can be said at this point is that the environment of the fetus can affect future behaviour in subtle ways, but how people regard themselves depends on how they are regarded.
Many babies are born each year with genitals that are hard to characterise. Yet there is immense pressure to complete a birth certificate, for which the criterion is whether the baby has a penis or not. In any case, it is something the parents want to know. We are told that, because of environmental pollution, such babies are becoming more common.
Corrective surgery is frequently performed on the child when it is too young to give its informed consent.
Because of the problems associated with effective penile surgery, it has become routine to operate on boys who are seriously affected and reassign them as girls. The rationale is that provided by Money, suggesting that gender identity is determined by the sex of rearing. Such children are said to be happy to become boys and girls, later men and women, though they might feel it wise not to discuss their feelings. However, a considerable number of people have raised their voices in recent years bitterly resenting this procedure, notably the Intersex Society of North America, with support of Diamond and others. The issues involved are discussed in more detail by Fausto-Sterling(5) and Dreger(6) and we have tried to give a flavour of them in the next section, Development.
A number of women who have had clitoral correction in childhood have expressed resentment about the loss of sensation. Given that they were otherwise perfectly capable of living a successful life, growing up and raising a family, one might consider intersexuality to be, at least partly, a clinical artifact.
The situation is less clear for young men who have surgery, usually for hypospadias, a condition where the urethra does not terminate at the tip of the penis. One man, at least, who has not had surgery, is refusing it. He points out that having grown up with it, he has learned to manage effectively without.
A major problem with far too many studies is that they are based on unstructured subjective personal reports or, at best, questionnaires that 'lead' the respondent. Moreover our view is biassed by inflammatory headlines and documentaries.
Those who were happy in the role assigned to them might well just disappear from view, while others might well have avoided clinics as far as possible, or said whatever would create the least fuss. One feels that the debate would be more balanced if we heard from those for whom the procedures had been a success.
Nevertheless, it would seem that, particularly in cases like these, the future sexual identity of a child can not be predicted with certainty.
Bibliography and Good Reading
Bland, J., (2001) About Gender: The Fetal Environment
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Derby TV/TS Group. Text copyright Jed Bland.
30.06.00 Last amended 11.11.01