Variations of sex development: The first German interdisciplinary consensus paper

Neurological Considerations for "Nerve-Sparing" Cosmetic Genital Surgeries Performed on Children with XX Chromosomes Diagnosed with 21-Hydroxylase Congenital Adrenal Hyperplasia and Clitoromegaly

Congenital adrenal hyperplasia (CAH) is most often caused by adrenal deficiency of 21-hydroxylase (21-OH). The resulting increase in androgens can cause clitoromegaly in fetuses with XX chromosomes. 21-OH CAH is the most common reason for cosmetic clitoroplasty in childhood. "Nerve-sparing" (NS) clitoral reduction surgeries are described as offering optimal cosmesis, while sparing sensation and nerve function. The methods used to demonstrate NS surgery efficacy, however, such as electromyography and optical coherence tomography, do not evaluate the small-fiber axons that comprise the majority of axons in the clitoris and that transduce sexual pleasure. Although some data show sparing of a portion of the main dorsal nerve trunk of the clitoris, the overall neurobiological consequences of elective clitoral reductions have received little attention. NS surgeries remove dorsal nerve branches that transduce sexual sensation, as well as the corpora cavernosa and cavernous nerve, which provide clitoral autonomic function. While most outcome studies focus on surgeons' perceptions of cosmetic results, studies that assess small-fiber function indicate significant nervous system and sexual impairment. Studies assessing children's clitoral function after surgery with vibrational testing have been ethically condemned. Decades of advocacy against medically unnecessary childhood genital surgeries have highlighted the subsequent physical and psychological harm. Recent studies with CAH patients indicate gender diversity and a lower prevalence of female gender identification than is often cited to justify feminizing surgery. The most effective and ethical NS technique for CAH may be acceptance of gender, sexual, and genital diversity as the infant develops into childhood, adolescence, and adulthood.

Privacy and ethical challenges of the Amelogenin sex test in forensic paternity/kinship analysis: Insights from a 13-year case history

The Amelogenin sex test included in forensic DNA typing kits has the potential to identify congenital conditions such as differences/disorders of sex development (DSD). It can also reveal mismatches between genotypic sex and gender marker in identity documents of transgender persons who obtained legal gender recognition. In a 13-year case history of paternity/kinship tests, involving n = 962 females and n = 1001 males, two mismatches between Amelogenin sex test (male) and gender marker (female), and three cases of chromosomal DSD (Klinefelter syndrome) were observed. The concrete risk of observing Amelogenin anomalies, their potential causes, and the context in which they occur (forensic, i.e. non-medical) mean that laboratory operators are called to strike a complex balance between privacy interests and individual health rights when providing preliminary information and reporting Amelogenin incidental findings. This case history argues for the need of a more responsible approach towards the Amelogenin sex test in the forensic community.

Contexts of care for people with differences of sex development: Diversity is still missing in the laboratory routine

The 2006 Chicago consensus statement of management of disorders/difference of sex development (DSD) has achieved advantages in clinical care and diagnosis for patients and families affect by DSD. This article provides a brief overview of contexts of care for physicians, and points out specific challenges in clinical practice that have arisen from the transformations of the sex/gender system in recent years. We focus on the impact of diagnosis and laboratory measurements. Both laboratory measurements and hormonal therapies still depend on the binary system. One problem is the lack of reference intervals for the different forms of DSD, which means that diversity is often neglected. In the following, we will give a brief insight into this complex topic.

Standards of Care for the Health of Transgender and Gender Diverse People, Version 8

Background: Transgender healthcare is a rapidly evolving interdisciplinary field. In the last decade, there has been an unprecedented increase in the number and visibility of transgender and gender diverse (TGD) people seeking support and gender-affirming medical treatment in parallel with a significant rise in the scientific literature in this area. The World Professional Association for Transgender Health (WPATH) is an international, multidisciplinary, professional association whose mission is to promote evidence-based care, education, research, public policy, and respect in transgender health. One of the main functions of WPATH is to promote the highest standards of health care for TGD people through the Standards of Care (SOC). The SOC was initially developed in 1979 and the last version (SOC-7) was published in 2012. In view of the increasing scientific evidence, WPATH commissioned a new version of the Standards of Care, the SOC-8. Aim: The overall goal of SOC-8 is to provide health care professionals (HCPs) with clinical guidance to assist TGD people in accessing safe and effective pathways to achieving lasting personal comfort with their gendered selves with the aim of optimizing their overall physical health, psychological well-being, and self-fulfillment. Methods: The SOC-8 is based on the best available science and expert professional consensus in transgender health. International professionals and stakeholders were selected to serve on the SOC-8 committee. Recommendation statements were developed based on data derived from independent systematic literature reviews, where available, background reviews and expert opinions. Grading of recommendations was based on the available evidence supporting interventions, a discussion of risks and harms, as well as the feasibility and acceptability within different contexts and country settings. Results: A total of 18 chapters were developed as part of the SOC-8. They contain recommendations for health care professionals who provide care and treatment for TGD people. Each of the recommendations is followed by explanatory text with relevant references. General areas related to transgender health are covered in the chapters Terminology, Global Applicability, Population Estimates, and Education. The chapters developed for the diverse population of TGD people include Assessment of Adults, Adolescents, Children, Nonbinary, Eunuchs, and Intersex Individuals, and people living in Institutional Environments. Finally, the chapters related to gender-affirming treatment are Hormone Therapy, Surgery and Postoperative Care, Voice and Communication, Primary Care, Reproductive Health, Sexual Health, and Mental Health. Conclusions: The SOC-8 guidelines are intended to be flexible to meet the diverse health care needs of TGD people globally. While adaptable, they offer standards for promoting optimal health care and guidance for the treatment of people experiencing gender incongruence. As in all previous versions of the SOC, the criteria set forth in this document for gender-affirming medical interventions are clinical guidelines; individual health care professionals and programs may modify these in consultation with the TGD person.

Diagnosis of DSD in Children—Development of New Tools for a Structured Diagnostic and Information Management Program within the Empower-DSD Study

Background: Current recommendations define a structured diagnostic process, transparent information, and psychosocial support by a specialized, multi-professional team as central in the care for children and adolescents with genital variations and a suspected difference of sex development (DSD). The active involvement of the child and their parents in shared decision-making should result in an individualized care plan. So far, this process has not been standardized. Methods: Within the Empower-DSD study, a team of professionals and representatives of patient advocacy groups developed a new diagnostic and information management program based on current recommendations and existing patient information. Results: The information management defines and standardizes generic care elements for the first weeks after a suspected DSD diagnosis. Three different tools were developed: a guideline for the specialized multiprofessional team, a personal health record and information kit for the child with DSD and their family, and a booklet for medical staff not specialized in DSD. Conclusions: The new information management offers guidance for patients and professionals during the first weeks after a DSD diagnosis is suspected. The developed tools’ evaluation will provide further insight into the diagnostic and information-sharing process as well as into all of the involved stakeholders’ needs.

Surgical Practice in Girls with Congenital Adrenal Hyperplasia: An International Registry Study

In this article international trends in surgical practice in girls with congenital adrenal hyperplasia (CAH) are evaluated. All cases that had been classified in the I-CAH/I-DSD registry as 46,XX CAH and who were born prior to 2017 were identified. Centers were approached to obtain information on surgical decision making. Of the 330 included participants, 208 (63.0%) presented within the first month of life, and 326 (98.8%) cases were assigned female. Genital surgery had been performed in 250 (75.8%). A total of 64.3, 89.2, and 96.8% of cases residing in Europe, South America and Asia, respectively, had at least one surgery. In a logistic regression model for the probability of surgery before the second birthday (early surgery) over time an increase of probability for early vaginal surgery could be identified, but not for clitoral surgery or both surgeries combined. Genitoplasty in girls with CAH remains controversial. This large international study provides a snapshot of current practice and reveals geographical and temporal differences. Fewer surgeries were reported for Europe, and there seems to be a significant trend towards aiming for vaginal surgery within the first 2 years of life.

Cholesterol Contributes to Male Sex Differentiation Through Its Developmental Role in Androgen Synthesis and Hedgehog Signaling

Two specialized functions of cholesterol during fetal development include serving as a precursor to androgen synthesis and supporting hedgehog (HH) signaling activity. Androgens are produced by the testes to facilitate masculinization of the fetus. Recent evidence shows that intricate interactions between the HH and androgen signaling pathways are required for optimal male sex differentiation and defects of either can cause birth anomalies indicative of 46,XY male variations of sex development (VSD). Further, perturbations in cholesterol synthesis can cause developmental defects, including VSD, that phenocopy those caused by disrupted androgen or HH signaling, highlighting the functional role of cholesterol in promoting male sex differentiation. In this review, we focus on the role of cholesterol in systemic androgen and local HH signaling events during fetal masculinization and their collective contributions to pediatric VSD.

The Health Care of Adults with Differences in Sex Development or Intersex Traits Is Changing: Time to Prepare Clinicians and Health Systems

Historically, the majority of differences in sex development or intersex trait (dsd/I)-specific medical care has been provided by pediatric clinicians, leading to a dearth of adult clinicians qualified to care for this vulnerable population, and pediatricians reticent to transition patients to adult care. Recent changes in routine care of children and infants with dsd/I, including reconsidering the role of early genital surgeries, highlight the critical need to address the gaps in adult dsd/I health care. In this perspective, we describe three key educational and research approaches that can be implemented to build competency to care for adults with dsd/I and improve care across the lifespan.

Self- and proxy-reported outcomes after surgery in people with disorders/differences of sex development (DSD) in Europe (dsd-LIFE)

BACKGROUND

Surgery is performed in many individuals with disorders/differences of sex development (DSD). Irreversibility of some surgical procedures, lack of information about the procedures, and lack of follow-up care for physical and psychological outcomes, lead to wish for more knowledge from both surgeons and patients. After the consensus conference in 2006, multidisciplinary care is provided to a higher degree with psychological support and more restricted surgical procedures. Outcome studies after genital surgery often lack of patient's perspective.

OBJECTIVE

To describe surgical procedures in relation to diagnosis, to evaluate the outcomes of surgery through genital examination, and through patient's and observer's satisfaction with the anatomical and functional result after genital surgery.

STUDY DESIGN

In a cross-sectional clinical study performed in six European countries in 2014/15, we have included 500 participants where surgery was performed, from a total of 1040 adolescents (≥16years) and adults with a DSD. Diagnoses included Turner syndrome (n = 301), mixed gonadal dysgenesis (45,XO/46,XY; n = 45), Klinefelter syndrome (n = 218), XYY (n = 1), 46, XY DSD (n = 222) and 46, XX DSD (n = 253). Study protocol included clinical report files, an optional gynecological or urological examination, patient reported outcomes including received surgical interventions, satisfaction with appearance and function after surgery, and impact of the surgical procedure on life.

RESULTS

Five hundred participants had received genital or breast surgery, with the highest rate in 46, XY DSD and the lowest in Turner syndrome. Altogether; 240 participants had feminizing surgery, 112 had masculinizing surgery, and 217 underwent gonadectomy. Physicians evaluated anatomical appearance at genital examination as poor in less than 10%. Dissatisfaction with anatomical appearance was reported by 22% of the participants, dissatisfaction with function by 20%. Being (very) dissatisfied with anatomical appearance and function was reported by 13% of the study participants. Most participants reported no impact, or positive impact, of the surgical procedures on their lives, but 29% experienced a negative effect of gonadectomy on their life.

DISCUSSION

There might be a selection bias and/or a recall bias for participating in our studies. Due to poor data quality about surgical procedures performed in the past, we also relied on participants memory about surgical procedures in their past. Ideally, patient reported outcomes should be evaluated both before and after surgical procedures.

CONCLUSION

A vast majority are satisfied with appearance and function, but still genital or breast surgery have a long-lasting effect on patient's life. Self-reported satisfaction is usually lower than the observer's evaluation regarding both appearance and function.

Intersex care in the United States and international standards of human rights

ABSTRACTDeeply rooted on human rights principles, there is a growing international agreement to prohibit non-consensual medical interventions to intersex persons. In contrast, medical protocols for intersex care in the United States are guided by clinical wisdom and guidelines that are not legally binding. But as the medical profession is called to respect and to champion the right to health within human rights principles, expert opinion in the United States has become unsettled when confronted with current standards of intersex care. In this study, we tracked the human rights arguments by international institutions that effectively impacted clinical standards for the care of intersex persons around the globe during this decade, and we studied the use of rhetoric by key policy stakeholders that seek to uphold intersex medical care in the United States to these international standards. We conclude that the medical establishment in the United States does not meet international standards of human rights as it enforces an outdated definition of 'sex'.

The role of androgens in clitorophallus development and possible applications to transgender patients

BACKGROUND

The clitorophallus, or glans, is a critical structure in sexual development and plays an important role in how gender is conceptualized across the life span. This can be seen in both the evaluation and treatment of intersex individuals and the use of gender-affirming masculinizing therapies to help those born with a clitoris (small clitorophallus with separate urethra) enlarge or alter the function of that structure.

OBJECTIVES

To review the role of testosterone in clitorophallus development from embryo to adulthood, including how exogenous testosterone is used to stimulate clitorophallus enlargement in masculinizing gender-affirming therapy.

MATERIALS AND METHODS

Relevant English-language literature was identified and evaluated for data regarding clitorophallus development in endosex and intersex individuals and the utilization of hormonal and surgical masculinizing therapies on the clitorophallus. Studies included evaluated the spectrum of terms regarding the clitorophallus (genital tubercle, clitoris, micropenis, penis).

RESULTS

Endogenous testosterone, and its more active metabolite dihydrotestosterone, plays an important role in the development of the genital tubercle into the clitorophallus, primarily during the prenatal and early postnatal periods and then again during puberty. Androgens contribute to not only growth but also the inclusion of a urethra on the ventral aspect. Exogenous testosterone can be used to enlarge the small clitorophallus (clitoris or micropenis) as part of both intersex and gender-affirming care (in transmasculine patients, up to 2 cm of additional growth). Where testosterone is insufficient to provide the degree of masculinization desired, surgical options including phalloplasty and metoidioplasty are available.

DISCUSSION AND CONCLUSION

Endogenous testosterone plays an important role in clitorophallus development, and there are circumstances where exogenous testosterone may be useful for masculinization. Surgical options may also help some patients reach their personal goals. As masculinizing gender-affirming care advances, the options available for clitorophallus modifications will likely continue to expand and improve.

'That decision really was mine…'. Insider perspectives on health care controversies about intersex/diverse sex development

After 20 years of debate on intersex care, there has been a slight movement away from the paradigm of 'optimal gender' including early genital modification to conform to predicted gender identity towards a paradigm of 'full consent' including the provision of full information about the risks, benefits and alternatives to interventions and the postponement of irreversible interventions on minors too young to give informed consent. However, controversy continues. Against this background, the aim of this study was to analyse core aspects of current debates in intersex care. Focus was placed on controversies about surgery on external genitalia; gonadectomies; the expressed wishes of patients under the age of consent; and how to deal with intersex within the family. Eight guideline-based interviews were conducted with two people with intersex/diverse sex development conditions who had been subjected to surgery, two parents of children with an intersex/dsd condition, two medical doctors, and two psychologists. Data were analysed thematically. Findings indicate that while 'full consent' influenced actions and debate, the persons involved held differing opinions about how this policy can or should be achieved. In addition, the data illustrated how concepts such as normalcy, identity and sexuality are relevant when dealing with intersex issues.

Participant- and Clinician-Reported Long-Term Outcomes After Surgery in Individuals with Complete Androgen Insensitivity Syndrome

STUDY OBJECTIVE

To evaluate the outcomes of genital surgery through participant's and observer's satisfaction with the anatomical and functional result.

DESIGN AND SETTING

Multicenter cross-sectional study in 14 clinics in 6 European countries in 2014-2015.

PARTICIPANTS

Seventy-one individuals with complete androgen insensitivity syndrome (≥16 years old).

INTERVENTIONS

Data from clinical report files, an optional gynecological examination, patient-reported outcomes on received surgical interventions, satisfaction with appearance and function after surgery, and effect of the surgical procedure on life.

MAIN OUTCOME MEASURES

Outcomes were calculated per different surgical treatments. Linear regression models were used for associations with vaginal satisfaction.

RESULTS

Sixty-three participants had received surgery: 62 gonadectomies, 12 vaginal surgeries with or without vaginal dilations, 9 vaginal dilations only, and 2 breast enlargements. More than half of the participants took part in the gynecological examination. Vaginal length was similar in those without (60 mm) and with (67 mm) vaginoplasty and/or vaginal dilations. Participant- and observer-reported appearance of the genitals were generally satisfactory to good. Sexual complaints (pain or bleeding during/after intercourse) were common. Vaginal satisfaction was strongly associated with satisfaction with sex life in general, whereas vaginal interventions and number of surgeries were not. Many participants reported a negative effect of gonadectomy on their life.

CONCLUSION

Despite good genital appearance, functional problems are commonly reported, across the different nonsurgical and surgical regimens. Patient-reported outcomes should be evaluated before and after surgical procedures. Because of the negative effect on life and the low risk of malignancy, gonadectomy should be deferred to adulthood with regular follow-up.

Psychosocial care and support in the field of intersex/diverse sex development (dsd): counselling experiences, localisation and needed improvements

From different sides, there is a call for better psychosocial care and counselling in the field of diverse sex development (dsd). However, studies on the specific demands, deficits and needed improvements regarding those services are rare. This exploratory online study aimed at investigating counselling experiences and the ideas that different groups of participants have concerning the localisation of counselling structures and improving care. Quantitative and qualitative data (N = 630) were analysed within a mixed methods framework. The participants included experts of experience resp. patients with different intersex/dsd conditions (n = 40), parents of children with dsd (n = 27), professional psychosocial counsellors (n = 321) and experts in the field including medical practitioners, psychologists, natural and social scientists as well as others involved, e.g., students or relatives (n = 56). The results show a gap between receiving psychosocial and medical care in the group of adult lived-experience experts, who had received less psychosocial care than medical interventions. The findings also reveal important tasks of psychosocial care. A focus was set on parental experiences. Helpful aspects reported were talking with other parents of children with intersex/dsd, aspects missed were assistance in supporting the individual development of their children. The majority of all participants (58%) held the view that, apart from multidisciplinary competence centres, there also have to be easily accessible counselling services which offer support in everyday life. The participants named increasing quality and quantity as necessary improvements in counselling structures for children and adults with intersex/dsd and their families. Implications are drawn for the specific tasks and target groups of psychosocial care and needed research in intersex healthcare over life span.

[Disorders of sex differentiation: state of the problem 15 years after the Chicago consensus]

It is well known that the nomenclature and classification were changed in 2005 at the international consensus conference on intersex disorders, held in Chicago, where, among others, the following recommendations were proposed: (1) all children should be assigned a gender identity, and this should be done as quickly as possible, taking into account the time required for the examination. (2) all infants with congenital adrenal hyperplasia and 46,XX karyotype, including those with pronounced masculinization, must be raised as women. (3) Surgical treatment should be performed early and in cases of feminizing genitoplasty, clitoral reduction should be performed simultaneously with reconstruction of the urogenital sinus (separation of the vagina and urethra). An analysis of contemporary literature shows that all these theories, proposed 15 years ago at the Chicago meeting, failed to stand the test of time. New nomenclature and classification are constantly being revised. Currently, many groups of patients want to abolish the term «sexual maturity disorders.» Recommendations regarding gender reassignment and appropriate early surgical treatment have been completely ignored in some countries. All this was largely facilitated by the confrontational activities of a number of support groups.

Dealing With Uncertainty and Lack of Knowledge in Diverse Sex Development: Controversies on Early Surgery and Questions of Consent

INTRODUCTION

Diverse sex development (dsd) is an umbrella term for different congenital conditions with incongruence of chromosomal, gonadal, and phenotypic sex characteristics. These are accompanied by various uncertainties concerning health-related, medical, psychosocial, and legal issues that raise controversial discussion.

AIM

The aim of this exploratory study was to investigate 3 questions: What are the most controversial and disputed issues in the context of intersex/dsd? Which issues are associated with the biggest knowledge gaps? Which issues involve the greatest difficulty or uncertainty in decision-making? A further aim was to investigate whether the group of persons concerned, the parents of intersex children, and the group of experts in the field had differing views regarding these questions.

METHODS

A self-developed questionnaire was distributed among persons concerned, parents of children with intersex/dsd, and experts in the field. It contained open and multiple-choice questions. The answers from 29 participants were entered into data analysis. A mixed-method approach was applied. Quantitative data were analysed descriptively. Qualitative data were analysed according to the principles of qualitative content analysis.

MAIN OUTCOME MEASURE

Participants answered questions on the most controversial and disputed issues, issues associated with the biggest knowledge gaps, and issues associated with the most difficulty or uncertainty in decision-making.

RESULTS

The findings indicate that controversial issues and uncertainties mainly revolve around surgical interventions but also around the question of how to adequately consider the consent of minors and how to deal with intersex in the family. Significant differences were found between persons concerned and parents vs academic experts in the field regarding the perceptions of procedure of diagnostic investigation and/or treatment in adulthood, on legal questions concerning marriage/registered civil partnerships, and on lack of psychosocial counseling close to place of residence.

CONCLUSION

The necessity of irreversible gonadal and genital surgery in early childhood is still a matter of strong controversy. To ensure the improvement in well-being of intersex persons, including a sexual health perspective, the positive acceptance of bodily variance is an important prerequisite. Psychosocial support regarding one-time decisions as well as ongoing and changing issues of everyday life appears to be an important means in reaching overall quality of life. Lampalzer U, Briken P, Schweizer K. Dealing With Uncertainty and Lack of Knowledge in Diverse Sex Development: Controversies on Early Surgery and Questions of Consent-A Pilot Study. Sex Med 2020;8:472-489.

Under-reported aspects of diagnosis and treatment addressed in the Dutch-Flemish guideline for comprehensive diagnostics in disorders/differences of sex development

We present key points from the updated Dutch-Flemish guideline on comprehensive diagnostics in disorders/differences of sex development (DSD) that have not been widely addressed in the current (inter)national literature. These points are of interest to physicians working in DSD (expert) centres and to professionals who come across persons with a DSD but have no (or limited) experience in this area. The Dutch-Flemish guideline is based on internationally accepted principles. Recent initiatives striving for uniform high-quality care across Europe, and beyond, such as the completed COST action 1303 and the European Reference Network for rare endocrine conditions (EndoERN), have generated several excellent papers covering nearly all aspects of DSD. The Dutch-Flemish guideline follows these international consensus papers and covers a number of other topics relevant to daily practice. For instance, although next-generation sequencing (NGS)-based molecular diagnostics are becoming the gold standard for genetic evaluation, it can be difficult to prove variant causality or relate the genotype to the clinical presentation. Network formation and centralisation are essential to promote functional studies that assess the effects of genetic variants and to the correct histological assessment of gonadal material from DSD patients, as well as allowing for maximisation of expertise and possible cost reductions. The Dutch-Flemish guidelines uniquely address three aspects of DSD. First, we propose an algorithm for counselling and diagnostic evaluation when a DSD is suspected prenatally, a clinical situation that is becoming more common. Referral to ultrasound sonographers and obstetricians who are part of a DSD team is increasingly important here. Second, we pay special attention to healthcare professionals not working within a DSD centre as they are often the first to diagnose or suspect a DSD, but are not regularly exposed to DSDs and may have limited experience. Their thoughtful communication to patients, carers and colleagues, and the accessibility of protocols for first-line management and efficient referral are essential. Careful communication in the prenatal to neonatal period and the adolescent to adult transition are equally important and relatively under-reported in the literature. Third, we discuss the timing of (NGS-based) molecular diagnostics in the initial workup of new patients and in people with a diagnosis made solely on clinical grounds or those who had earlier genetic testing that is not compatible with current state-of-the-art diagnostics.

46,XX DSD due to Androgen Excess in Monogenic Disorders of Steroidogenesis: Genetic, Biochemical, and Clinical Features

The term 'differences of sex development' (DSD) refers to a group of congenital conditions that are associated with atypical development of chromosomal, gonadal, or anatomical sex. Disorders of steroidogenesis comprise autosomal recessive conditions that affect adrenal and gonadal enzymes and are responsible for some conditions of 46,XX DSD where hyperandrogenism interferes with chromosomal and gonadal sex development. Congenital adrenal hyperplasias (CAHs) are disorders of steroidogenesis that mainly involve the adrenals (21-hydroxylase and 11-hydroxylase deficiencies) and sometimes the gonads (3-beta-hydroxysteroidodehydrogenase and P450-oxidoreductase); in contrast, aromatase deficiency mainly involves the steroidogenetic activity of the gonads. This review describes the main genetic, biochemical, and clinical features that apply to the abovementioned conditions. The activities of the steroidogenetic enzymes are modulated by post-translational modifications and cofactors, particularly electron-donating redox partners. The incidences of the rare forms of CAH vary with ethnicity and geography. The elucidation of the precise roles of these enzymes and cofactors has been significantly facilitated by the identification of the genetic bases of rare disorders of steroidogenesis. Understanding steroidogenesis is important to our comprehension of differences in sexual development and other processes that are related to human reproduction and fertility, particularly those that involve androgen excess as consequence of their impairment.