Fetal endocrine therapy for congenital adrenal hyperplasia should not be done

Pregnancy and Prenatal Management of Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive diseases that may cause cortisol insufficiency together with other hormonal alterations. The most common form is 21-hydroxylase deficiency, in which the lack of pituitary negative feedback causes an increase in ACTH and adrenal androgens. Classical forms of CAHs can lead to severe adrenal failure and female virilization. To date, the appropriate management of pregnant CAH patients is still debated regarding appropriate maternal therapy modifications during pregnancy and the risks and benefits of prenatal treatment of the fetus. We conducted a literature search of relevant papers to collect current evidence and experiences on the topic. The most recent and significant articles were selected, and current international guidelines were consulted to update current recommendations and guide clinical practice. Given the lack of randomized clinical trials and other high-quality scientific evidence, the issue is still debated, and great heterogeneity exists in current practice in terms of risk/benefit evaluation and pharmacological choices for pregnancy and prenatal treatment. Glucocorticoid therapy is advised not only in classical CAH patients but also in non-classical, milder forms. The choice of which glucocorticoid to use, and the safety and benefits of dexamethasone therapy aimed at preventing genital virilization are still debated issues. Several advances, however, have been made, especially in terms of fertility and reproduction. This review aims to present the most recent scientific and real-world updates on pregnancy and prenatal management of CAH, with the presentation of various clinical scenarios and specific case-by-case recommendations.

First Trimester Dexamethasone Treatment Is Not Associated With Alteration in Resting-state Connectivity at Adolescent or Adult Age

CONTEXT

Prenatal treatment with dexamethasone (DEX) has been used to prevent virilization in females at risk of congenital adrenal hyperplasia (CAH). Both affected and unaffected girls, as well boys, are treated until the genotype and sex of the fetus is known (gestational weeks 10-12). After that, only affected girls are treated until term. Exposure to a high synthetic glucocorticoid dosage may alter the developmental trajectory of the brain, with alterations in resting-state functional connectivity of the brain at adult age.

OBJECTIVE

To investigate resting-state functional connectivity in subjects at risk of having CAH, exposed to DEX treatment during the first trimester of fetal life, both in the whole brain and in 3 regions of interest (amygdala, hippocampus, and superior frontal gyrus).

DESIGN, SETTING, AND PARTICIPANTS

Eighteen participants (8 females) at risk of having CAH, exposed to DEX treatment, and 38 controls (24 females), age range 16 to 26 years, from a single research institute, underwent functional magnetic resonance imaging of the brain during rest. We used 2 different approaches: an exploratory whole-brain analysis and seed-based analysis. For seed-based analysis, we chose 3 different brain regions (amygdala, hippocampus, and superior frontal gyrus) based on our previous findings and literature evidence.

RESULTS

We did not observe any differences in functional connectivity during rest, either in the whole brain nor in seed-based connectivity analyses at this adolescent and young adult age.

CONCLUSIONS

Our results are reassuring; however, future studies on larger samples and with more sensitive methodologies are needed to confirm these findings.

Ambulatory Blood Pressure Monitoring in Children and Adults Prenatally Exposed to Dexamethasone Treatment

CONTEXT

The clinical use of dexamethasone (DEX) prenatally to reduce virilization of external genitalia in female fetuses with congenital adrenal hyperplasia (CAH) is efficient but still controversial. It remains challenging to prevent the excessive exposure of DEX in unborn healthy babies during the first trimester of pregnancy.

OBJECTIVE

Since endogenous glucocorticoids contribute to the maintenance of blood pressure (BP) and since events during fetal life may program the fetus and affect future metabolic health, the aim of this study was to analyze ambulatory BP measurements in CAH-unaffected children and adults that were prenatally exposed to DEX treatment.

METHODS

Ambulatory BP measurements were analyzed in 33 (16 female) DEX-treated participants aged 5.1 to 26.3 years (19 participants aged ≤ 18 years) and in 54 (28 female) age- and sex-matched apparently healthy controls aged 5.5 to 25.3 years (27 participants aged ≤ 18 years) with ambulatory normotension.

RESULTS

Participants' age, height, weight, and body mass index were similar between the DEX-treated group and the control group. Heart rate, 24-hour BP, pulse pressure, and nighttime dipping did not statistically significantly differ between DEX-treated participants and controls.

CONCLUSION

Our study suggests that prenatal DEX treatment in CAH-unaffected children and adults does not appear to adversely affect ambulatory BP later in life. Our observations need to be confirmed in larger studies.

Prenatal dexamethasone treatment for classic 21-hydroxylase deficiency in Europe

OBJECTIVE

To assess the current medical practice in Europe regarding prenatal dexamethasone (Pdex) treatment of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency.

DESIGN AND METHODS

A questionnaire was designed and distributed, including 17 questions collecting quantitative and qualitative data. Thirty-six medical centres from 14 European countries responded and 30 out of 36 centres were reference centres of the European Reference Network on Rare Endocrine Conditions, EndoERN.

RESULTS

Pdex treatment is currently provided by 36% of the surveyed centres. The treatment is initiated by different specialties, that is paediatricians, endocrinologists, gynaecologists or geneticists. Regarding the starting point of Pdex, 23% stated to initiate therapy at 4-5 weeks postconception (wpc), 31% at 6 wpc and 46 % as early as pregnancy is confirmed and before 7 wpc at the latest. A dose of 20 µg/kg/day is used. Dose distribution among the centres varies from once to thrice daily. Prenatal diagnostics for treated cases are conducted in 72% of the responding centres. Cases treated per country and year vary between 0.5 and 8.25. Registries for long-term follow-up are only available at 46% of the centres that are using Pdex treatment. National registries are only available in Sweden and France.

CONCLUSIONS

This study reveals a high international variability and discrepancy in the use of Pdex treatment across Europe. It highlights the importance of a European cooperation initiative for a joint international prospective trial to establish evidence-based guidelines on prenatal diagnostics, treatment and follow-up of pregnancies at risk for CAH.

Congenital Adrenal Hyperplasia-Current Insights in Pathophysiology, Diagnostics, and Management

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders affecting cortisol biosynthesis. Reduced activity of an enzyme required for cortisol production leads to chronic overstimulation of the adrenal cortex and accumulation of precursors proximal to the blocked enzymatic step. The most common form of CAH is caused by steroid 21-hydroxylase deficiency due to mutations in CYP21A2. Since the last publication summarizing CAH in Endocrine Reviews in 2000, there have been numerous new developments. These include more detailed understanding of steroidogenic pathways, refinements in neonatal screening, improved diagnostic measurements utilizing chromatography and mass spectrometry coupled with steroid profiling, and improved genotyping methods. Clinical trials of alternative medications and modes of delivery have been recently completed or are under way. Genetic and cell-based treatments are being explored. A large body of data concerning long-term outcomes in patients affected by CAH, including psychosexual well-being, has been enhanced by the establishment of disease registries. This review provides the reader with current insights in CAH with special attention to these new developments.

First Trimester DEX Treatment Is Not Associated with Altered Brain Activity During Working Memory Performance in Adults

CONTEXT

Prenatal dexamethasone (DEX) treatment is sometimes used in pregnancies at risk for congenital adrenal hyperplasia (CAH) to prevent virilization in female fetuses with CAH. In boys and in fetuses not having CAH, there is no benefit of early DEX treatment and the risks of this therapy must be thoroughly investigated. High doses of prenatal glucocorticoid might alter the developmental trajectory of the brain into adulthood, even for CAH unaffected subjects treated with DEX for a short term during the first trimester.

OBJECTIVE

The present study investigated brain activation during working memory performance in DEX-treated subjects compared with controls.

DESIGN, SETTING, AND PARTICIPANTS

We tested 18 participants who were exposed to DEX during the first trimester of fetal life but did not have CAH (8 females; mean age 20.78 [standard deviation (SD), 2.67] years) and 40 control participants (24 females; mean age 20.53 [SD, 2.64]) from a single research institute. Participants underwent functional magnetic resonance imaging on a 3T scanner during a verbal and visuospatial working memory task.

RESULTS

We did not observe any differences in brain activity during working memory performance. However, DEX-treated subjects responded faster during the experimental condition of the verbal WM task.

CONCLUSIONS

First trimester DEX treatment did not seem to result in altered working memory-related brain activity at adult age. Our findings contribute to the risk-benefit assessment of prenatal DEX treatment in the context of CAH.

First-Trimester Prenatal Dexamethasone Treatment Is Associated With Alterations in Brain Structure at Adult Age

CONTEXT

Prenatal treatment of human disease is rare. Dexamethasone (DEX) is used in pregnancies at risk for congenital adrenal hyperplasia (CAH) to prevent virilization in an affected female fetus. The safety and long-term consequences of prenatal DEX exposure on the brain are largely unknown.

OBJECTIVE

We investigate whether first-trimester prenatal DEX treatment is associated with alterations in brain structure at adult age, and if these alterations are associated with DNA methylation, mood, and cognitive abilities.

DESIGN, SETTING, AND PARTICIPANTS

T1-weighted and diffusion-weighted imaging scans, from a single research institute, are compared between 19 (9 women) first-trimester DEX-treated individuals, at risk of CAH but not having CAH, and 43 (26 women) controls (age range, 16.0-26.4 years).

RESULTS

DEX-treated participants showed bilateral enlargement of the amygdala, increased surface area and volume of the left superior frontal gyrus, and widespread increased radial, mean, and axial diffusivity of white matter, in particular in the superior longitudinal fasciculi and corticospinal tracts. In the DEX-treated group, increased mean and radial diffusivity correlated with increased methylation of the promotor region of the FKBP5 gene. There were no group differences in cognition or in scales assessing depression or anxiety, and the relationship between brain structure and cognition did not differ between DEX-treated and controls.

CONCLUSIONS

First-trimester prenatal DEX treatment is associated with structural alterations of the brain at adult age, with an accompanying change in gene methylation. The findings add to the safety concerns of prenatal DEX treatment in the context of CAH.

EMQN best practice guidelines for molecular genetic testing and reporting of 21-hydroxylase deficiency

Molecular genetic testing for congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD) is offered worldwide and is of importance for differential diagnosis, carrier detection and adequate genetic counseling, particularly for family planning. In 2008 the European Molecular Genetics Quality Network (EMQN) for the first time offered a European-wide external quality assessment scheme for CAH (due to 21-OH deficiency). The interest was great and over the last years at about 60 laboratories from Europe, USA and Australia regularly participated in that scheme. These best practice guidelines were drafted on the basis of the extensive knowledge and experience got from those annually organized CAH-schemes. In order to obtain the widest possible consultation with practicing laboratories the draft was therefore circulated twice by EMQN to all laboratories participating in the EQA-scheme for CAH genotyping and was updated by that input. The present guidelines address quality requirements for diagnostic molecular genetic laboratories, as well as criteria for CYP21A2 genotyping (including carrier-testing and prenatal diagnosis). A key aspect of that article is the use of appropriate methodologies (e.g., sequencing methods, MLPA (multiplex ligation dependent probe amplification), mutation specific assays) and respective limitations and analytical accuracy. Moreover, these guidelines focus on classification of variants, and the interpretation and standardization of the reporting of CYP21A2 genotyping results. In addition, the article provides a comprehensive list of common as well as so far unreported CYP21A2-variants.

Good overall behavioural adjustment in children and adolescents with classic congenital adrenal hyperplasia

PURPOSE

Patients with classic congenital adrenal hyperplasia (CAH) are treated postnatally with life-long glucocorticoid (GC) replacement therapy. Although prolonged exposure to GCs may have a negative impact on behaviour, few studies have studied this issue. We therefore investigated behavioural outcomes in male and female children and adolescents with CAH.

METHODS

An observational study in which Swedish and Italian children and adolescents with CAH identified through neonatal screening for CAH (n = 57, age range 7-17 years) were compared with healthy population controls matched for age and sex (n = 72, age range 7-17 years). Thirteen (eight females) of the fifty-seven children and adolescents with CAH had been treated prenatally with dexamethasone (DEX). Standardised questionnaires for parents and self-report scales for children/adolescents were used to assess behavioural and emotional problems, social anxiety, temperament and scholastic competence.

RESULTS

There were no statistically significant differences between CAH patients (not prenatally treated with DEX) and controls on most of the scales measuring adaptive functioning or behavioural problems. However, children with CAH were rated by their parents to have more social problems than controls (Child Behaviour Checklist, CBCL social problems, p = 0.032). In the small group (n = 13) of prenatally DEX-treated cases parents rated their children/adolescents to have more mood problems compared with non-DEX-treated children/adolescents with CAH (CBCL-withdrawn/depressed, p = 0.019).

CONCLUSION

Children/adolescents with CAH showed good overall adjustment. The clinical significance of the parentally perceived increase in social problems in children/adolescents with CAH requires further investigation. The findings underline the importance of psychological support for children/adolescents with a chronic condition.

Cognitive Function of Children and Adolescents With Congenital Adrenal Hyperplasia: Importance of Early Diagnosis

CONTEXT

Patients with classic congenital adrenal hyperplasia (CAH) are treated postnatally with lifelong glucocorticoid (GC) replacement therapy. Previous results on general cognitive ability in individuals with CAH have been conflicting.

OBJECTIVE

To evaluate long-term cognitive effects of GC replacement therapy and the impact of early diagnosis in children with CAH.

DESIGN AND SETTING

Observational study with patients from a single research institute.

PATIENTS

32 children with CAH (mean age 11.5 years) identified through the Swedish national neonatal screening program for CAH and 52 matched population controls (mean age 10.7 years). Eleven (6 female) children with CAH who were treated prenatally with dexamethasone (DEX), (CAH-DEX) (mean age 11.7 years).

INTERVENTION

GC replacement therapy, neonatal screening for CAH.

MEASURES

Cognitive abilities assessed with standardized neuropsychological tests (Wechsler scales, Span Board Test, Stroop Interference Test, NEPSY list learning).

RESULTS

Children with CAH (not prenatally treated) performed equally well as population controls on a series of tests assessing general intellectual ability and executive functions. No significant differences were observed in cognitive performance between patients with different genotypes (null, non-null). Patients with salt-wasting CAH performed poorer than patients with simple virilizing CAH in a test assessing visuo-spatial working memory (P = 0.039), although the performance was within the normal range for the population. Prenatally DEX-treated girls with CAH had lower verbal intellectual ability compared with CAH girls not exposed to prenatal treatment (P = 0.037).

CONCLUSION

Children and adolescents with CAH who were diagnosed early via a neonatal screening program and treated with hydrocortisone had normal psychometric intelligence and executive functions.

Exposure to Glucocorticoids in the First Part of Fetal Life is Associated with Insulin Secretory Defect in Adult Humans

OBJECTIVE

High glucocorticoid levels in rodents inhibit development of beta cells during fetal life and lead to insulin deficiency in adulthood. To test whether similar phenomena occur in humans, we compared beta-cell function in adults who were exposed to glucocorticoids during the first part of fetal life with that of nonexposed subjects.

RESEARCH DESIGN AND METHODS

The study was conducted in 16 adult participants exposed to glucocorticoids during the first part of fetal life and in 16 nonexposed healthy participants with normal glucose tolerance who were matched for age, sex, and body mass index (BMI). Exposed participants had been born to mothers who were treated with dexamethasone 1 to 1.5 mg/day from the sixth gestational week (GW) to prevent genital virilization in children at risk of 21-hydroxylase deficiency. We selected offspring of mothers who stopped dexamethasone before the 18th GW following negative genotyping of the fetus. Insulin and glucagon secretion were measured during an oral glucose tolerance test (OGTT) and graded intravenous (IV) glucose and arginine tests. Insulin sensitivity was measured by hyperinsulinemic-euglycemic-clamp.

RESULTS

Age, BMI, and anthropometric characteristics were similar in the 2 groups. Insulinogenic index during OGTT and insulin sensitivity during the clamp were similar in the 2 groups. In exposed subjects, insulin secretion during graded IV glucose infusion and after arginine administration decreased by 17% (P = 0.02) and 22% (P = 0.002), respectively, while glucagon secretion after arginine increased.

CONCLUSION

Overexposure to glucocorticoids during the first part of fetal life is associated with lower insulin secretion at adult age, which may lead to abnormal glucose tolerance later in life.

Pregnancy in Congenital Adrenal Hyperplasia

Fertility rates in classic congenital adrenal hyperplasia caused by 21-hydroxylase deficiency are substantially decreased for various reasons, including hormonal, anatomic, psychosocial, and psychosexual causes. However, fecundity is comparable with the general population. Under optimal hormone replacement, the course and outcome of pregnancies is also good. This article summarizes successful gestational management, including preconceptional considerations, adjustment of hormone replacement during pregnancy, delivery and lactation, as well as the prevention of adrenal crises. In nonclassic 21-hydroxylase deficiency, preconceptional low-dose hydrocortisone replacement normalizes the otherwise increased miscarriage rate. Pregnancy reports in rarer forms of congenital adrenal hyperplasia are summarized as well.

Prenatal Treatment of Congenital Adrenal Hyperplasia: Long-Term Effects of Excess Glucocorticoid Exposure

Prenatal treatment of congenital adrenal hyperplasia with dexamethasone (DEX) has been in use since the mid-1980s and has proven effective at reducing virilization of external genitalia in affected girls. However, multiple experimental studies on animals and clinical studies on humans show that prenatal administration of glucocorticoids may cause unwanted adverse effects which have raised concerns about the long-term safety of the treatment. The long-term outcome of prenatal DEX treatment on cognition has been investigated, but the results are still conflicting. Overall, most of the evidence points towards a negative effect on executive functions where girls seem to be more susceptible than boys. Some effects on social behavior have been observed, but results are still contradictory and treated children are mostly well adapted. Cardiovascular, renal, and metabolic function are still areas to be investigated. Larger studies are warranted to investigate areas other than cognition and behavior and to be able to draw more definitive conclusions about prenatal DEX treatment.

Evaluation of behavioral problems after prenatal dexamethasone treatment in Swedish children and adolescents at risk of congenital adrenal hyperplasia

Prenatal dexamethasone (DEX) treatment in congenital adrenal hyperplasia (CAH) is effective in reducing virilization in affected girls, but potential long-term adverse effects are largely unknown. In this report we intended to explore potential side effects of DEX therapy to enhance the adequacy of future risk benefit analyses of DEX treatment. We investigated the long-term effects of first trimester prenatal DEX treatment on behavioral problems and temperament in children and adolescents aged 7-17 years. The study included 34 children and adolescents, without CAH, who had been exposed to DEX during the first trimester and 67 untreated controls. Standardized parent-completed questionnaires were used to evaluate adaptive functioning and behavioral/emotional problems (CBCL), social anxiety (SPAI-C-P), and temperament (EAS) in the child. Self-reports were used to assess the children's perception of social anxiety (SASC-R). No statistically significant differences were found between DEX-treated and control children and adolescents, suggesting that, in general, healthy children treated with DEX during early fetal life are well adjusted.

Nouveautés dans l’hyperplasie congénitale des surrénales

Congenital adrenal hyperplasia is an autosomal recessive disease due to functional abnormalities of adrenal steroid enzymes. The most common form of the disease is due to a 21-hydroxylase deficiency. The classical forms (most severe) are characterized by a deficiency in cortisol and sometimes in aldosterone, which may compromise the vital prognosis of neonates, and by an increase in androgen synthesis, leading to the virilization of girls' external genitalia at birth, followed by clinical signs of hyperandrogenism during childhood and adolescence. Neonatal screening has improved management and reduced morbidity and mortality in the neonatal period, but its performance could be broadly optimised by adjusting the assay techniques or the biomarkers used. The genetic diagnosis is difficult owing to the large genetic heterogeneity of the 6p21.3 region, which contains the CYP21A2 gene, especially with respect to the use of new-generation techniques of sequencing. Prenatal diagnosis is now possible as early as 6 weeks of gestation, but prenatal treatment remains controversial, awaiting results from prospective cohorts evaluating its long-term impact. Since conventional therapies have limitations, new therapies are currently being developed to allow better control of androgen synthesis and a substitutive treatment that respects the physiological rhythm of cortisol secretion, which would limit the development of long-term complications.

MANAGEMENT OF ENDOCRINE DISEASE: Congenital adrenal hyperplasia due to 21-hydroxylase deficiency: update on the management of adult patients and prenatal treatment

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is characterized by cortisol and in some cases aldosterone deficiency associated with androgen excess. Goals of treatment are to replace deficient hormones and control androgen excess, while avoiding the adverse effects of exogenous glucocorticoid. Over the last 5 years, cohorts of adults with CAH due to 21-hydroxylase deficiency from Europe and the United States have been described, allowing us to have a better knowledge of long-term complications of the disease and its treatment. Patients with CAH have increased mortality, morbidity and risk for infertility and metabolic disorders. These comorbidities are due in part to the drawbacks of the currently available glucocorticoid therapy. Consequently, novel therapies are being developed and studied in an attempt to improve patient outcomes. New management strategies in the care of pregnancies at risk for congenital adrenal hyperplasia using fetal sex determination and dexamethasone have also been described, but remain a subject of debate. We focused the present overview on the data published in the last 5 years, concentrating on studies dealing with cardiovascular risk, fertility, treatment and prenatal management in adults with classic CAH to provide the reader with an updated review on this rapidly evolving field of knowledge.

Steroid 21-hydroxylase deficiency in congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) refers to a group of inherited genetic disorders involving deficiencies in enzymes that convert cholesterol to cortisol within the adrenal cortex. There are five key enzymes involved in the production of cortisol. Of these key enzymes, deficiency of 21-hydroxylase is the most commonly defective enzyme leading to CAH representing more than 90% of cases. The low adrenal cortisol levels associated with CAH affects the hypothalamic-pituitary-adrenal negative feedback system leading to increased pituitary adrenocorticotropic hormone (ACTH) production, which overstimulates the adrenal cortex in an attempt to increase cortisol production resulting in a hyperplastic adrenal cortex. The deficiency of enzyme 21-hydroxylase results from mutations or deletions in the CYP21A2 gene found on chromosome 6p. The disorder is transmitted as an autosomal recessive pattern and specific mutations may be correlated to enzymatic compromise of varying degrees, leading to the clinical manifestation of 21-hydroxylase deficiency (21-OHD) CAH.

RETRACTED: Evaluation of behavioral problems after prenatal dexamethasone treatment in Swedish adolescents at risk of CAH

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors due to technical errors that have called into question the reliability of the data used to inform the author's conclusions. All data on cognitive and behavioral outcomes in CAH and non–CAH cases, treated or not treated with DEX prenatally, were put into a single Excel database. The authors had in total four different patient groups for each age group (5–6 y, 7–17 y and 18-35 y). The database consisted of 237 cases in total and there were multiple columns for the different outcome measures. When the behavioral data for the sub-cohort described in this paper (first trimester treated non-CAH cases and healthy population controls, age 7–17 y) were copied to another sheet and compressed/modified in preparation for statistical analysis in SPSS, an error occurred. This technological issue caused rows to shift and the data from the different groups got mixed up. In particular, the non–CAH group versus the control group were "contaminated" with cases from the wrong patient group. The authors discovered this mistake when they started to analyse the data from the other sub–groups of patients, the CAH cases and the adult cohort, which was after their original results had already been published in Hormones and Behavior in this manuscript "Evaluation of behavioral problems after prenatal dexamethasone treatment in Swedish adolescents at risk of CAH". It then became apparent that the entire data set was unreliable and needed to be re–analysed which is what has motivated the retraction of this article. The authors have recently completed this re–analysis and the results have been published here: https://www.sciencedirect.com/science/article/pii/S0018506X17300752

Preventing female virilisation in congenital adrenal hyperplasia: The controversial role of antenatal dexamethasone

Congenital adrenal hyperplasia (CAH) refers to a group of recessively inherited disorders of cortisol production, which in the classical form results in virilisation of female fetuses. Since the 1980s, antenatal treatment with dexamethasone has been recommended in high-risk pregnancies to minimise the risk of virilising the female genitalia of affected fetuses. To be effective, this treatment requires implementation in early pregnancy, prior to the commencement of autonomous fetal adrenal androgen synthesis. Using this approach, seven of eight high-risk pregnancies are treated unnecessarily, prior to establishing the fetal gender or the confirmed diagnosis of a genetically affected pregnancy. In the face of ongoing concerns regarding potential adverse maternal-fetal effects of antenatal dexamethasone exposure, a review of this practice has been advocated by expert advisory groups. In this review, we summarise current controversies, potential improvements and future directions in the management of pregnancies at risk of CAH. In high-risk families, recent genomic advances include early prenatal diagnosis utilising noninvasive genetic techniques to minimise unnecessary dexamethasone exposure to unaffected fetuses. In affected pregnancies when families elect for antenatal treatment, optimal antenatal dosing regimens need to be defined and a standardised treatment and follow-up protocol are recommended. Establishment of a national registry with standardised follow-up will allow future families to be better informed of the risks and benefits of both treated and untreated fetal CAH.

Overview of genetics of disorders of sexual development

PURPOSE OF REVIEW

Disorders of sexual development (DSD) are a genetic and phenotypic heterogeneous group of congenital disorders. This review focuses on the genetics of DSD and aims to recognize and contextualize, in a systematic way, based on the classification and the genetic mechanisms, the latest developments in the field of DSD diagnostics.

RECENT FINDINGS

Due to the current diagnostic armamentarium, during the past decade, the field of DSD diagnostics has changed dramatically from the recognition of few genes and cytogenetic abnormalities, to the identification of multiple genes and a wide arrange of genetic mechanisms involved in the genesis of DSD. In addition, the phenotypes associated with the genetic mechanism have expanded tremendously.

SUMMARY

Despite the current diagnostic limitations, the landscape for genetics of DSD is encouraging due to discovery of new genes, their interactions, and the recognition of the variety of mechanisms involved.