Counseling parents before prenatal diagnosis: Do we need to say more about the sex chromosome aneuploidies?

Parental questions about sex chromosome aneuploidies regarding sex, gender, and sexual orientation as reported by genetic counselors in a prenatal setting

The introduction of cell-free DNA screening has resulted in increased prenatal identification of sex chromosome aneuploidies (SCAs). This study aimed to evaluate genetic counselor experiences disclosing SCAs positive prenatal screening or testing results and genetic counselor-reported parental questions regarding sex, gender, and sexual orientation. Forty-eight prenatal genetic counselors completed the survey. When asked to quantify their experiences, 97.9% of counselors reported disclosing a SCAs positive screen result within the previous year, and 81.3% disclosed a diagnostic result. Of those counselors, 53.8% reported always or often receiving parental questions about sex, 33% always or often about gender, and 25% always or often regarding sexual orientation. Counselors were asked to share examples of parental questions following a positive screen or diagnostic testing for SCAs. Parental questions were stratified by karyotype and content analysis revealed questions about the fetus' sex, anatomy, reproduction, being cisgender, gender expression, behavior, being transgender, and sexual orientation. The examples of parental questions provided by genetic counselors suggested some parents may have misconceptions about the intersection of SCAs with sex, gender, and sexual orientation following prenatal screening or diagnostic testing. The majority of counselors (83.3%) agreed to some extent that they desired further education on responding to parental questions about SCAs. Findings from this research suggest a need for genetic counseling strategies that accurately and respectfully discuss SCAs in the context of sex, gender, and sexual orientation with prenatal patients.

The emotional journey of adapting to prenatally identified trisomy X

There is a paucity of research on the experiences of parents of children with trisomy X (47,XXX). Increased prenatal diagnoses associated with advances in noninvasive prenatal screening necessitate a better understanding of how trisomy X impacts family systems. This qualitative investigation aimed to describe the lived experience of parents of young daughters with prenatally identified trisomy X to guide genetic counseling. Semi-structured qualitative interviews were conducted via teleconferencing with parents (n = 11) of girls with trisomy X, ages 6-44 months. A descriptive phenomenological approach was used to code transcripts for significant statements and reduce data into themes describing the experience of receiving a diagnosis of trisomy X and the experience of early parenting in this population. Participants described an emotional journey of adapting to prenatally identified trisomy X. Four descriptive themes included two related, yet distinct, life stages: Negative Diagnostic Experience and a Hopeful Early Childhood, as well as two ongoing experiences: Persistent Ambiguity and Coping with and Adapting to Uncertainty. Results suggest providers should carefully consider word choice and timing in delivery of diagnosis, and genetic counseling should provide expectant parents with current research specific to trisomy X, facilitate connections with other parents of young girls with trisomy X, introduce developmental monitoring approaches, and be prepared to support families with a range of emotional responses to the diagnosis and decisions regarding disclosure.

Ethical issues associated with prenatal screening using non-invasive prenatal testing for sex chromosome aneuploidy

Prenatal screening for sex chromosome aneuploidies (SCAs) is increasingly available through expanded non-invasive prenatal testing (NIPT). NIPT for SCAs raises complex ethical issues for clinical providers, prospective parents and future children. This paper discusses the ethical issues that arise around NIPT for SCAs and current guidelines and protocols for management. The first section outlines current practice and the limitations of NIPT for SCAs. It then outlines key guidelines before discussing the ethical issues raised by this use of NIPT. We conclude that while screening for SCAs should be made available for people seeking to use NIPT, its implementation requires careful consideration of what, when and how information is provided to users.

Noninvasive prenatal screening (NIPS) results for participants of the eXtraordinarY babies study: Screening, counseling, diagnosis, and discordance

Sex chromosome aneuploidies (SCAs), including 47,XXY, 47,XXX, 47,XYY, and supernumerary variants, occur collectively in approximately one of 500 live births. Clinical phenotypes are highly variable resulting in previous ascertainment rates estimated to be only 10%-25% during a lifetime. Historically, prenatal SCA diagnoses were incidental findings, accounting for ≤10% of cases, with the majority of diagnoses occurring postnatally during evaluations for neurodevelopmental, medical, or infertility concerns. The initiation of noninvasive prenatal screening (NIPS) in 2012 and adoption into standardized obstetric care provides a unique opportunity to significantly increase prenatal ascertainment of SCAs. However, the impact NIPS has had on ascertainment of SCAs is understudied, particularly for those who may defer diagnostic testing until after birth. This study evaluates the timing of diagnostic testing following positive NIPS in 152 infants with SCAs and potential factors influencing this decision. Eighty-seven (57%) elected to defer diagnostic testing after a positive NIPS until birth, and 8% (7/87) of those confirmed after birth were found to have discordant results on postnatal diagnostic testing, most of which would have influenced genetic counseling.

Non-Invasive Prenatal Screening: The First Report of Pentasomy X Detected by Plasma Cell-Free DNA and Karyotype Analysis

Pentasomy X is a sex chromosome anomaly caused by the presence of three extra X chromosomes in females (49,XXXXX instead of 46,XX) and is probably due to a nondisjunction during the meiosis. So far, only five cases prenatally diagnosed were described. The main features in 49,XXXXX karyotype include severe intellectual disability with delayed speech development, short stature, facial dysmorphisms, osseous and articular abnormalities, congenital heart malformations, and skeletal and limb abnormalities. Prenatal diagnosis is often difficult due to the lack of a clear echographic sign like nuchal translucency (NT), and mostly cases were postnatally described. We report the first case of a 49,XXXXX female that was detected by non-invasive prenatal screening (NIPS), quantitative fluorescence polymerase chain reaction (QF-PCR) and a fetal karyotype.

Cell-Free DNA Screening for Sex Chromosome Abnormalities and Pregnancy Outcomes, 2018-2020: A Retrospective Analysis

To evaluate the efficacy of non-invasive prenatal screening (NIPT) for detecting fetal sex chromosome abnormalities, a total of 639 women carrying sex chromosome abnormalities were selected from 222,107 pregnant women who participated in free NIPT from April 2018 to December 2020. The clinical data, prenatal diagnosis results, and follow-up pregnancy outcomes of participants were collected. The positive predictive value (PPV) was used to analyze the performance of NIPT. Around 235 cases were confirmed with sex chromosome abnormalities, including 229 cases with sex chromosome aneuploidy (45, X (n = 37), 47, XXX (n = 37), 47, XXY (n = 110), 47, XYY (n = 42)) and 6 cases with structural abnormalities. The total incidence rate was 0.11% (235/222,107). The PPV of NIPT was 45.37% (235/518). NIPT accuracy for detecting sex chromosome polysomes was higher than that for sex chromosome monomers. The termination of pregnancy rate for fetal diagnosis of 45, X, and 47, XXY was higher than that of 47, XXX, and 47, XYY. The detection rate of fetal sex chromosome abnormalities was higher in 2018–2020 than in 2010–2012 (χ² = 69.708, P < 2.2 × 10⁻¹⁶), indicating that NIPT is greatly efficient to detect fetal sex chromosome abnormalities.

An assessment of the analytical performance of non-invasive prenatal testing (NIPT) in detecting sex chromosome aneuploidies: 34,717-patient sample in a single prenatal diagnosis Centre in China

OBJECTIVE

The present study aimed to evaluate the efficacy of a non-invasive prenatal test (NIPT) in the detection of the sex chromosome aneuploidies (SCAs) at our prenatal diagnosis centre.

METHODS

Among a cohort of 34,717 pregnancies, maternal plasma samples from our prenatal diagnosis centre were subject to analysis of SCAs using NIPT detection. Pregnant women with NIPT positive results of SCAs were recommended to undergo an invasive prenatal diagnosis (i.e. karyotyping and fluorescence in situ hybridization) to validate the prediction value of NIPT.

RESULTS

From 34,717 clinical pregnancies, 229 (0.66%) pregnancies were identified with SCAs. Of these, 78 (34.1%) cases were positive for 45,X and 151 (65.9%) cases comprised a sex chromosome trisomy. Of the 229 positive NIPT results, 193 (84.3%) cases had accepted an invasive diagnosis involving karyotyping analysis of the amniotic fluid, which confirmed 67 cases (34.7%) as true positive, as well as 126 cases (65.3%) as false positive. The positive predictive values were 23.07%, 50%, 36% and 27.27% respectively. The remaining 36 (15.7%) cases declined a prenatal diagnosis. The termination rates of 45,X, 47,XXY, 47,XXX and 47,XYY were 20.5%,46%,12.9% and 11.5% respectively.

CONCLUSIONS

NIPT demonstrated a lower accuracy in predicting monosomy X than sex chromosome trisomies. After invasive testing, the fetal chromosome with 45,X and 47,XXY were terminated more often than those with 47,XXX, 47,XYY. Because NIPT is a screening test, false positive/negative cases exist, and pre- and post-test counselling is essential for informing patients about the benefits and limitations of the test. Confirmatory testing of abnormal results is recommended prenatally or after birth, and the importance of confirmatory testing and benefits of early diagnosis should be addressed.

Noninvasive prenatal screening for fetal sex chromosome aneuploidies

INTRODUCTION

Sex chromosome aneuploidies (SCAs) are among the most common chromosome abnormalities observed in humans. Manifestations include low fertility, infertility, delayed language development, and dysfunction in motor development. Noninvasive prenatal screening (NIPS) based on cell-free fetal DNA from the peripheral blood of pregnant women is increasingly used for the screening of fetal chromosome abnormalities, including screening for fetal gender and fetal sex chromosome aneuploidy. A systematic review of the literature about NIPS for SCAs is needed.

AREAS COVERED

This review evaluated a vast array of published studies focusing on the clinical significance, detection methods, performance of NIPS for SCAs, and the management of positive SCA results following screening with the aim of facilitating a comprehensive and systematic understanding of NIPS for SCAs.

EXPERT COMMENTARY

Looking forward, NIPS is expected to become the primary screening test for common aneuploidies as well as other chromosome abnormalities, including some micro-deletions and micro-duplications, with the potential to transition from a screening test to a prenatal diagnosis method. Ultimately, the goal is to provide a safe and accurate method for increasing early diagnosis to improve long-term outcomes for the SCA patients and families by well- informed health care providers.

Family experiences and attitudes about receiving the diagnosis of sex chromosome aneuploidy in a child

The most common sex chromosome aneuploidies (SCA) (47, XXY; 47, XYY; 47, XXX) frequently result in a milder phenotype than autosomal aneuploidies. Nevertheless, these conditions are highly variable and more symptomatic phenotypes may require significant clinical involvement, including specialty care. While historically most individuals with mild phenotypes remained undiagnosed during their lifetime, the increasing use of genetic testing in clinical care has increased the prenatal and postnatal diagnosis of SCAs. These genetic tests are frequently ordered by nongenetic providers who are also responsible for delivering the diagnosis. We surveyed parents of children (n = 308) to evaluate their experience of receiving a diagnosis and their support needs. The majority (73.3%) received the diagnosis from a nongenetic medical provider. Following a prenatal diagnosis parents reported experiencing depression, anxiety, and less optimism than those receiving a postnatal diagnosis. Few parents reported receiving materials explaining their child's condition that they found to be up-to-date, accurate, and unbiased. The frequently negative reported experiences of parents at time of diagnosis suggests more educational opportunities should be provided for nongenetic providers in order to become more informed about these conditions and communicate the diagnosis in a way parents experience as supportive.

Cognitive Profile, Emotional-Behavioral Features, and Parental Stress in Boys With 47,XYY Syndrome

OBJECTIVE

To describe (a) the observed cognitive, emotional, and behavioral phenotype in a cohort of male children with 47,XYY syndrome and (b) stress levels in their parents.

METHODS

We conducted a cross-sectional observational study of 11 boys diagnosed with 47,XYY syndrome and compared them with 11 age-matched boys with normal karyotype (46,XY). The participants performed standardized assessments of cognitive function, emotional state, and behavioral features; the parents completed a questionnaire evaluating parental stress. All data were analyzed using parametric and nonparametric statistical methods.

RESULTS

All of the boys exhibited a normal cognitive profile. However, emotional-behavioral profiling revealed that internalizing and externalizing problems were more prevalent in the 47,XYY group. In addition, the stress levels of the parents of the 47,XYY group were reportedly higher than those of the parents of the 46,XY group. We also found that the time of the diagnosis had an effect on the mothers' stress levels; that is, postnatal fetal 47,XYY diagnosis was associated with higher maternal stress, whereas prenatal fetal 47,XYY diagnosis was not.

CONCLUSIONS

Generally, 47,XYY syndrome is associated with certain cognitive, emotional, and behavioral features. High stress levels have been reported by the mothers of 47,XYY boys who had been diagnosed postnatally because of unexpected developmental delay and/or learning difficulties. The present study highlights the need to better define the neuropsychiatric phenotype of 47,XYY children; namely, the effect of the chromosomal abnormality on their cognitive function and emotional-behavioral (internalizing and externalizing) features. This study could improve prenatal counseling and pediatric surveillance.

Screening, prenatal diagnosis, and prenatal decision for sex chromosome aneuploidy

Objective: To assess the performance of non-invasive prenatal testing (NIPT) in screening sex chromosome aneuploidy (SCA), and explore prenatal decision-making in NIPT positive cases. Methods: The study retrospectively analyses singleton pregnancies who underwent NIPT screening. Clinical data, diagnostic results, and pregnancy outcomes were also collected. Results: There were 140 positive screens for SCA, including 62 cases of 45,X, 29 cases with 47,XXX, 28 cases of 47,XXY, 20 cases of 47,XYY, and one case of lower X chromosome. Karyotypic information was available in 103 cases. The positive predictive value was 26.09% for 45,X, 85.00% for 47,XXX, 85.00% for 47,XXY, and 68.75% for 47,XYY. The termination rates of 45,X, 47,XXX, 47,XXY, 47,XYY were 83.33%, 26.67%, 82.35%, and 54.54%, respectively (not including mosaic cases). Conclusion: Our findings demonstrated that the NIPT performed better in predicting sex chromosome trisomies than monosomy X even though false-positive cases do exist in NIPT. For prenatal decisions, pregnancies with diagnoses of fetal 45,X and 47,XXY were terminated more often than those with 47,XXX, 47,XYY. To better guide positive screening pregnancies, pre- and post-test counseling are essential in telling patients the benefits and limitations of the test, comforting their anxiety and giving them the choice for further diagnosis and pregnancy decision.

Delivering the Diagnosis of Sex Chromosome Aneuploidy: Experiences and Preferences of Parents and Individuals

Increased prenatal diagnoses of sex chromosome aneuploidies (SCAs) amid limited knowledge of their prognoses heighten the need to understand how families contend with the implications of an SCA. To explore the experiences of parents and individuals who received a genetic diagnosis of an SCA (excluding Turner syndrome), we conducted semistructured qualitative telephone interviews with 43 participants affected by these conditions. Parents (n = 35) and individuals (n = 8) expressed almost unanimous interest in more optimistic portrayals of their condition from their providers, even when the prognosis is uncertain. While some participants reported success in receiving accurate information from their provider and identifying supportive resources, numerous families received outdated or misleading information about their condition and lacked direction in accessing follow-up care and support. Parents desire greater coordination of their child's medical care and access to care that approaches an SCA holistically. Opportunities remain to improve the diagnosis and care of individuals with SCAs.

Klinefelter syndrome: more than hypogonadism

Klinefelter syndrome (KS) is the most frequent chromosome disorder in males (1:650 newborn males), defined by 47,XXY karyotype. The classical phenotype is that of a tall male with relatively long legs, small, firm testes and gynecomastia. Azoospermia and infertility are almost inevitably present, but may be overcome by TESE and ICSI. Nevertheless, a broad spectrum of phenotypes has been described and more than 70% of the actually existing KS men may remain undiagnosed throughout their lifespan. Accordingly, hypogonadism is usually not evident until early adulthood and progresses with ageing. KS patients present a series of comorbidities that increase morbidity and mortality by 40%. Such disturbances are the impaired metabolic profile (obesity, dyslipidemia, insulin resistance) and a tendency to thrombosis, which all favor cardiovascular disease. They also present susceptibility for specific neoplasias (breast cancer, extragonadal germ cell tumors), autoimmune diseases as well as osteoporosis and bone fractures. Moreover, KS has been associated with verbal processing and attention deficits as well as social skill impairments, leading KS individuals to academic and professional achievements inferior to those of their peers of comparable socio-economic status. Nevertheless, the majority fall within the average range regarding their intellectual abilities and adaptive functioning. Testosterone replacement therapy (TRT) is the mainstay of treatment in hypogonadal KS patients; however, randomized trials are needed to determine optimal therapeutic regimens and follow-up schedules.

The Impact of Living with Klinefelter Syndrome: A Qualitative Exploration of Adolescents and Adults

Klinefelter syndrome (XXY) is a common yet significantly underdiagnosed condition with considerable medical, psychological and social implications. Many health care providers lack familiarity with XXY, resulting in medical management challenges and a limited understanding of the personal impact of the condition. Genetic counselors benefit from understanding the challenges adolescents and men with XXY face to effectively address their medical and psychosocial needs. The purpose of this study was to understand the impact of living with XXY as an adolescent or an adult. Individuals aged 14 to 75 years with self-reported XXY were recruited from online support networks to complete a web-based survey that included open-ended questions. Open-ended responses were coded and analyzed thematically (n = 169 to 210 for each open-ended question). Over half of respondents to the open-ended questions reported challenges in finding health care providers who are knowledgeable about XXY, with many describing an extensive diagnostic odyssey and relief when receiving a diagnosis. Individuals sought support coping with the challenges they face and acknowledgement of the positive aspects of XXY. Recommendations are made for how genetic counseling can enhance quality of life for individuals living with XXY.

Expanding the phenotype of Triple X syndrome: A comparison of prenatal versus postnatal diagnosis

Triple X syndrome (47, XXX) occurs in approximately 1:1,000 female births and has a variable phenotype of physical and psychological features. Prenatal diagnosis rates of 47, XXX are increasing due to non-invasive prenatal genetic testing. Previous studies suggest that prenatal diagnosed females have better neurodevelopmental outcomes. This cross-sectional study describes diagnosis, physical features, medical problems, and neurodevelopmental features in a large cohort of females with 47, XXX. Evaluation included review of medical and developmental history, physical exam, cognitive, and adaptive testing. Medical and developmental features were compared between the prenatal and postnatal diagnosis groups using rate calculations and Fisher's exact test. Cognitive and adaptive tests scores were compared using t-tests. Seventy-four females age 6 months-24 years (mean 8.3 years) participated. Forty-four (59.5%) females were in the prenatal diagnosis group. Mean age of postnatal diagnosis was 5.9 years; developmental delay was the most common indication for postnatal genetic testing. Common physical features included hypertelorism, epicanthal folds, clinodactyly, and hypotonia. Medical problems included dental disorders (44.4%), seizure disorders (16.2%), genitourinary malformations (12.2%). The prenatal diagnosis group had higher verbal (P < 0.001), general ability index (P = 0.004), and adaptive functioning scores (P < 0.001). Rates of ADHD (52.2% vs. 45.5%, P = 0.77) and learning disabilities (39.1% vs. 36.3%, P = 1.00) were similar between the two groups. These findings expand on the phenotypic features in females with Triple X syndrome and support that prenatally ascertained females have better cognitive and functional outcomes. However, prenatally diagnosed females are still at risk for neurodevelopmental disorders. Genetic counseling and treatment recommendations are summarized. © 2016 Wiley Periodicals, Inc.