Maternal age-specific rates of fetal chromosomal abnormalities in Korean pregnant women of advanced maternal age

Application of Chromosomal Karyotype Analysis Combined With Chromosomal Microarray Analysis in the Amniotic Fluid of Advanced Maternal Age

OBJECTIVE

To explore the application and value of chromosomal karyotype analysis combined with Chromosomal Microarray Analysis (CMA) in the amniotic fluid of advanced maternal age.

METHODS

A total of 817 advanced maternal age (AMA) who underwent amniocentesis at the Prenatal Diagnosis Center of Huizhou Central People's Hospital between January 2018 and July 2024 were enrolled in this study. The women were grouped based on different age ranges and prenatal diagnosis factors. These groups were used to compare the detection rates and differences between chromosomal karyotype analysis and CMA.

RESULT

The overall chromosomal abnormality rates detected by karyotype analysis in the 35-39 years age group and the ≥ 40 years age group were 8.81% and 13.79%, respectively, with a statistically significant difference (p < 0.05). For CMA, the overall abnormality rates in the same age groups were 10.79% and 15.33%, respectively, but the difference was not statistically significant (p > 0.05). The non-solely advanced-age group (those with additional factors beyond just advanced age) had higher overall chromosomal abnormality rates, aneuploidy rates, structural abnormality rates, and mosaicism rates compared to the solely advanced-age group, with statistically significant differences (p < 0.05). Additionally, the non-solely advanced-age group had a higher overall abnormality rate detected by CMA compared to the solely advanced-age group, with a statistically significant difference (p < 0.05). However, there were no statistically significant differences between the two groups in terms of the detection of pathogenic, likely pathogenic, and variants of uncertain significance (p > 0.05). In this study, a total of 68 cases were identified where the results of karyotype analysis and CMA were inconsistent.

CONCLUSION

The overall abnormal rate of chromosomal karyotype analysis increases with maternal age, while the overall abnormal rate of CMA shows no significant correlation with maternal age. The abnormal rates are significantly higher in AMA with additional factors. The combination of chromosomal karyotype analysis and CMA can validate and complement each other, thereby improving the detection rates of chromosomal abnormalities in amniotic fluid samples of AMA. This provides a diagnostic basis for subsequent pregnancy choices, which effectively reduces the birth of fetuses with chromosomal abnormalities and enhances population quality.

Fetal karyotyping in adolescent pregnancies: a population-based cohort study on outcomes of invasive prenatal testing

Background

Adolescent pregnancies present unique challenges in prenatal diagnostics, yet data on the prevalence and types of chromosomal abnormalities in this population remain limited.

Objective

This study aimed to assess the prevalence and spectrum of chromosomal abnormalities and evaluate the effectiveness of invasive prenatal diagnostic procedures.

Methods

A retrospective cohort study analyzed data from invasive prenatal diagnostic procedures (amniocentesis and transabdominal chorionic villus sampling) and fetal karyotyping in adolescent pregnancies, comparing them with data obtained from pregnancies in older women.

Results

Abnormal karyotype prevalence varied by age. Trisomies were least frequent in adolescents (5.9%) vs. women 20-34 (9.3%) and ≥35 years (12.1%). Turner syndrome was more common in adolescents (4.6%) than in women 20-34 (2.8%) or ≥35 years (0.1%). Adolescents had a higher risk of unspecified fetal sex (RR = 2.25, 95% CI: 1.16-4.35) and culture failure (RR = 4.32, 95% CI: 2.07-9.00). Ultrasound abnormalities were the main reason for invasive testing (86.3%, p < 0.001). More chorionic villus sampling procedures were needed per abnormal karyotype in adolescents (3.25) vs. women 20-34 (2.42) or ≥35 years (2.19), while fewer amniocenteses were required (6.68 vs. 7.37 and 8.44).

Conclusion

Adolescents show unique chromosomal abnormalities, underscoring the need for tailored prenatal counseling and diagnostics.

WES-based screening of 7,000 newborns: A pilot study in Russia

The effective implementation of whole-exome sequencing- and whole-genome sequencing-based diagnostics in the management of children affected with genetic diseases and the rapid decrease in the cost of next-generation sequencing (NGS) enables the expansion of this method to newborn genetic screening programs. Such NGS-based screening greatly increases the number of diseases that can be detected compared to conventional newborn screening, as the latter is aimed at early detection of a limited number of inborn diseases. Moreover, genetic testing provides new possibilities for family members of the proband, as many variants responsible for adult-onset conditions are inherited from the parents. However, the idea of NGS-based screening in healthy children raises issues of medical and ethical integrity as well as technical questions, including interpretation of the observed variants. Pilot studies have shown that both parents and medical professionals have moved forward and are enthused about these new possibilities. However, either the number of participants or the number of genes studied in previous investigations thus far has been limited to a few hundred, restricting the scope of potential findings. Our current study (NCT05325749) includes 7,000 apparently healthy infants born at our center between February 2021 and May 2023, who were screened for pathogenic variants in 2,350 genes. Clinically significant variants associated with early-onset diseases that can be treated, prevented, or where symptoms can be alleviated with timely introduced symptomatic therapy, were observed in 0.9% of phenotypically normal infants, 2.1% of the screened newborns were found to carry variants associated with reduced penetrance or monogenic diseases of adult-onset and/or variable expressivity, and 0.3% had chromosomal abnormalities. Here, we report our results and address questions regarding the interpretation of variants in newborns who were presumed to be healthy.

Reproductive Ageing: Metabolic contribution to age-related chromosome missegregation in mammalian oocytes

In brief

Chromosome missegregation and declining energy metabolism are considered to be unrelated features of oocyte ageing that contribute to poor reproductive outcomes. Given the bioenergetic cost of chromosome segregation, we propose here that altered energy metabolism during ageing may be an underlying cause of age-related chromosome missegregation and aneuploidy.

Abstract

Advanced reproductive age in women is a major cause of infertility, miscarriage and congenital abnormalities. This is principally caused by a decrease in oocyte quality and developmental competence with age. Oocyte ageing is characterised by an increase in chromosome missegregation and aneuploidy. However, the underlying mechanisms of age-related aneuploidy have not been fully elucidated and are still under active investigation. In addition to chromosome missegregation, oocyte ageing is also accompanied by metabolic dysfunction. In this review, we integrate old and new perspectives on oocyte ageing, chromosome segregation and metabolism in mammalian oocytes and make direct links between these processes. We consider age-related alterations to chromosome segregation machinery, including the loss of cohesion, microtubule stability and the integrity of the spindle assembly checkpoint. We focus on how metabolic dysfunction in the ageing oocyte disrupts chromosome segregation machinery to contribute to and exacerbate age-related aneuploidy. More specifically, we discuss how mitochondrial function, ATP production and the generation of free radicals are altered during ageing. We also explore recent developments in oocyte metabolic ageing, including altered redox reactions (NAD+ metabolism) and the interactions between oocytes and their somatic nurse cells. Throughout the review, we integrate the mechanisms by which changes in oocyte metabolism influence age-related chromosome missegregation.

Smoking and recurrent pregnancy loss: A cohort study of 2829 women

Smoking during pregnancy is associated with negative reproductive outcome. Less is known about the impact of smoking or previous smoking in women with recurrent pregnancy loss (RPL) which this study aimed to investigate. We included all women <42 years (n=2829) referred to a RPL unit at Copenhagen University Hospital between January 2000 and December 2021 in the cohort with follow-up until June 2022. Patients were categorized as 'smokers at time of referral', 'never-smokers' or 'former smokers'. The main outcomes were pregnancy history prior to referral, prospective pregnancy rate, live birth rate, rates of ectopic pregnancy, and stillbirth. At referral, smokers (n=373) were on average 2.0 years younger (P<0.001) and had experienced significantly more pregnancy losses (P<0.001), and stillbirths (P=0.01) compared to never-smokers (n=2100). Former smokers had a higher risk of stillbirth prior to referral compared to never-smokers but no differences in pregnancy rate or other outcomes. Prospective pregnancy rates were lower for smokers compared with never-smokers (71.8% vs. 77.5%, P=0.02). Live birth rate was 58.0% for the 243 women who smoked at referral compared to 61.4% for the 1488 never-smokers (P=0.32). Stillbirth and ectopic pregnancies were significantly more common for smokers (2.8% vs. 0.4%, P=0.01; 6.0% vs. 2.0%, P<0.008). Women with RPL who smoked at referral were referred younger with a higher number of previous pregnancy losses and stillbirths compared with never-smokers. Fewer smokers achieved a pregnancy after referral but those who did had a similar live birth rate compared to never-smokers, although stillbirths and ectopic pregnancies were more common.

The influence of advanced maternal age on congenital malformations, short- and long-term outcomes in offspring of nulligravida: a Korean National Cohort Study over 15 years

OBJECTIVE

To assess the influence of advanced maternal age on congenital malformations, short- and long-term outcomes in offspring of nulligravida.

METHODS

A retrospective study was conducted using the Korean National Health Insurance Service database spanning from January 2005 to December 2019. All live-born offspring of nulligravida (n=3,685,817) were included. The maternal age was subdivided into the following subgroups: <25 years (n=153,818), 25-29 years (n=845,355), 30-34 years (n=1,738,299), 35-39 years (n=787,530), 40-44 years (n=151,519), and >44 years (n=9,296). Outcomes were assessed based on International Classification of Diseases-10 codes. Adjusted odds ratios (aOR) were calculated with the group of 25-29 years as a reference.

RESULT

Most congenital malformations showed an age dependent increase, but cleft lip and abdominal wall defect exhibited a U-shape curve, indicating an increase even in those <25 years old. Similarly, various disorders included in the neonatal composite outcomes from short-term outcomes showed aged dependent escalation. However, the preterm birth from the short-term outcome and most of the long-term developmental outcomes, except for motor developmental delay and Tics, showed a U-shaped pattern. The aOR of autism and cerebral palsy, showing the most obvious U-shaped curved in the long-term outcomes, was 1.50 (95% confidence interval [CI], 1.24-1.82) and 1.54 (95% CI, 1.17-2.03), respectively in the group >44 years old and 1.18 (95% CI, 1.11-1.25) and 1.19 (95% CI, 1.09-1.30) in <25 years old group.

CONCLUSION

Overall, an advanced maternal age has an age-dependent correlation with most congenital malformations and shortand long-term outcomes of neonates.

An extra X chromosome among adult women in the Million Veteran Program: A more benign perspective of trisomy X

Despite affecting in 1 in every 1000 females, remarkably little is known about trisomy X syndrome (47,XXX), especially among older adults who are undiagnosed. In this study, we aimed to determine the prevalence of 47,XXX among females enrolled in the Million Veterans Program (MVP; mean age 50.2 ± 13.6 years), and compare broad health outcomes between females with 47,XXX and 46,XX matched controls. We identified 61 females with an additional X chromosome, corresponding to a prevalence of 103 per 100,000 females; 27.9% had been clinically diagnosed. Females with 47,XXX had taller stature (+6.1 cm, p < 0.001), greater rate of outpatient encounters (p = 0.026), higher odds of kidney disease (odds ratio [OR] = 12.3; 95% confidence interval [CI] 2.9-51.8), glaucoma (OR = 5.1; 95% CI 1.5-13.9), and congestive heart failure (OR = 5.6; 95% CI 1.4-24.2), and were more likely to be unemployed (p = 0.008) with lower annual income (p = 0.021) when compared with 46,XX controls of the same age and genetic ancestry. However, there were no differences in the rates of other encounter types, Charlson Comorbidity Index, all other medical and psychological diagnoses, military service history or quality of life metrics. In conclusion, in this aging and predominately undiagnosed sample, 47,XXX conferred few differences when compared with matched controls, offering a more reassuring perspective to the trisomy X literature.

Maternal age and the risk of fetal aneuploidy: A nationwide cohort study of more than 500 000 singleton pregnancies in Denmark from 2008 to 2017

INTRODUCTION

In this register-based study of pregnancies in Denmark, we assessed the associations between maternal age and the risk of fetal aneuploidies (trisomy 21, trisomy 18, trisomy 13, triploidy, monosomy X and other sex chromosome aberrations). Additionally, we aimed to disentangle the maternal age-related effect on fetal aneuploidies by cases with translocation trisomies and mosaicisms.

MATERIAL AND METHODS

We followed a nationwide cohort of 542 375 singleton-pregnant women attending first trimester screening in Denmark between 2008 and 2017 until delivery, miscarriage or termination of pregnancy. We used six maternal age categories and retrieved information on genetically confirmed aneuploidies of the fetus and infant from the national cytogenetic register.

RESULTS

We confirmed the known associations between advanced maternal age and higher risk of trisomy 21, 18, 13 and other sex chromosome aberrations, especially in women aged ≥35 years, whereas we found no age-related associations with triploidy or monosomy X. Cases with translocation trisomies and mosaicisms did not influence the overall reported association between maternal age and aneuploidies.

CONCLUSION

This study provides insight into the accurate risk of fetal aneuploidies that pregnant women of advanced ages encounter.

Prospective prenatal cell-free DNA screening for genetic conditions of heterogenous etiologies

Prenatal cell-free DNA (cfDNA) screening uses extracellular fetal DNA circulating in the peripheral blood of pregnant women to detect prevalent fetal chromosomal anomalies. However, numerous severe conditions with underlying single-gene defects are not included in current prenatal cfDNA screening. In this prospective, multicenter and observational study, pregnant women at elevated risk for fetal genetic conditions were enrolled for a cfDNA screening test based on coordinative allele-aware target enrichment sequencing. This test encompasses the following three of the most frequent pathogenic genetic variations: aneuploidies, microdeletions and monogenic variants. The cfDNA screening results were compared to invasive prenatal or postnatal diagnostic test results for 1,090 qualified participants. The comprehensive cfDNA screening detected a genetic alteration in 135 pregnancies with 98.5% sensitivity and 99.3% specificity relative to standard diagnostics. Of 876 fetuses with suspected structural anomalies on ultrasound examination, comprehensive cfDNA screening identified 55 (56.1%) aneuploidies, 6 (6.1%) microdeletions and 37 (37.8%) single-gene pathogenic variants. The inclusion of targeted monogenic conditions alongside chromosomal aberrations led to a 60.7% increase (from 61 to 98) in the detection rate. Overall, these data provide preliminary evidence that a comprehensive cfDNA screening test can accurately identify fetal pathogenic variants at both the chromosome and single-gene levels in high-risk pregnancies through a noninvasive approach, which has the potential to improve prenatal evaluation of fetal risks for severe genetic conditions arising from heterogenous molecular etiologies. ClinicalTrials.gov registration: ChiCTR2100045739 .

The association between parental age differences and perinatal outcomes

STUDY QUESTION

Are there significant associations existing between parental age differences and adverse perinatal outcomes?

SUMMARY ANSWER

Large differences in parental age are associated with adverse perinatal outcomes, particularly with older mothers paired with younger fathers.

WHAT IS KNOWN ALREADY

The association between advanced maternal age and perinatal outcomes is well-documented with women over 35 years showing an increased risk of several adverse outcomes. Other studies have identified potential associations between advanced paternal age and adverse perinatal outcomes.

STUDY DESIGN, SIZE, DURATION

A historical (retrospective) cohort analysis was performed utilizing a multivariable logistic regression model to evaluate the association between varying differences in parental age and adverse perinatal outcomes while controlling for demographic and health-related covariates. Data were compiled from the National Vital Statistics System for 20 613 704 births between 2012 and 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Parental age differences, categorized into eleven 4-year intervals, were stratified by seven maternal age categories and evaluated for their associations with adverse perinatal outcomes. Main outcome measures included low birth weight, very low birth weight, preterm birth, very preterm birth, small size for gestational age, low 5-min appearance, pulse, grimace, activity, and respiration score, congenital defects, and chromosomal anomalies.

MAIN RESULTS AND THE ROLE OF CHANCE

Increased parental age differences, in either direction, were associated with significant risks for all adverse outcomes, aside from congenital defects, even when controlling for maternal age. Restricting maternal age to the reference range of 25-29 years, infants born to fathers aged 9-12 years younger (n = 3773) had 27% (odds ratio (OR) 1.27, 95% CI, 1.17-1.37) higher odds of having any adverse perinatal outcome. Infants born to fathers aged >16 years older (n = 98 555) had 14% (OR 1.14, 95% CI, 1.12-1.16) higher odds of having any adverse perinatal outcome.

LIMITATIONS, REASONS FOR CAUTION

Data extracted from US birth certificates may be compromised by errors in reporting or documentation. Information regarding the mother's socioeconomic status was estimated using proxy variables and may be susceptible to uncontrolled factors. Use of a pre-compiled dataset may potentially exclude additional maternal comorbidities that could impact perinatal outcomes.

WIDER IMPLICATIONS OF FINDINGS

Older mothers paired with younger fathers demonstrated the highest risk, even when maternal age was below the threshold of 35 years. For the clinical setting, parental age differences should be considered alongside maternal and paternal age when assessing risks of adverse perinatal outcomes for potential parents. This is particularly relevant for older women with younger male partners as this may exacerbate the impact of advanced maternal age.

STUDY FUNDING/COMPETING INTEREST(S)

This research was funded by the NIH Research Fellowship T35 Training Grant. There are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Effect of noninvasive embryo viability testing versus conventional IVF on the live birth rate in IVF/ICSI patients: a study protocol for a double-blind, multicenter, randomized controlled trial

BACKGROUND

Preimplantation genetic testing for aneuploidy (PGT-A) was demonstrated to be superior to conventional IVF in reducing the incidence of miscarriage and abnormal offspring after the first embryo transfer (ET). PGT-A requires several embryo trophectoderm cells, but its negative impacts on embryo development and long-term influence on the health conditions of conceived children have always been a concern. As an alternative, noninvasive PGT-A (niPGT-A) approaches using spent blastocyst culture medium (SBCM) achieved comparable accuracy with PGT-A in several pilot studies. The main objective of this study is to determine whether noninvasive embryo viability testing (niEVT) results in better clinical outcomes than conventional IVF after the first embryo transfer. Furthermore, we further investigated whether niEVT results in higher the live birth rate between women with advanced maternal age (AMA, > 35 years old) and young women or among patients for whom different fertilization protocols are adopted.

METHODS

This study will be a double-blind, multicenter, randomized controlled trial (RCT) studying patients of different ages (20-43 years) undergoing different fertilization protocols (in vitro fertilization [IVF] or intracytoplasmic sperm injection [ICSI]). We will enroll 1140 patients at eight reproductive medical centers over 24 months. Eligible patients should have at least two good-quality blastocysts (better than grade 4 CB). The primary outcome will be the live birth rate of the first embryo transfer (ET). Secondary outcomes will include the clinical pregnancy rate, ongoing pregnancy rate, miscarriage rate, cumulative live birth rate, ectopic pregnancy rate, and time to pregnancy.

DISCUSSION

In this study, patients who undergo noninvasive embryo viability testing (niEVT) will be compared to women treated by conventional IVF. We will determine the effects on the pregnancy rate, miscarriage rate, and live birth rate and adverse events. We will also investigate whether there is any difference in clinical outcomes among patients with different ages and fertilization protocols (IVF/ICSI). This trial will provide clinical evidence of the effect of noninvasive embryo viability testing on the clinical outcomes of the first embryo transfer.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR) Identifier: ChiCTR2100051408. 9 September 2021.

Expansion of non-invasive prenatal screening to the screening of 10 types of chromosomal anomalies: a cost-effectiveness analysis

OBJECTIVES

To determine the cost-effectiveness of the addition of chromosomal anomalies detectable by non-invasive prenatal screening (NIPS), in a prenatal screening programme targeting common aneuploidies.

DESIGN, SETTING AND PARTICIPANTS

A simulation study was conducted to study the addition of chromosomal anomalies detectable by NIPS (sex chromosome aneuploidies, 22q11.2 deletion syndrome, large deletion/duplication >7 Mb and rare autosomal trisomies) to five basic strategies currently aiming the common trisomies: three strategies currently offered by the public healthcare systems in Canada, whose first-tier test is performed with biochemical markers, and two programmes whose first-tier test consists of NIPS-based methods.

OUTCOME MEASURES

The total number of cases of chromosomal anomalies detected and the costs related to the consumption of medical services.

RESULTS

The most effective and the most cost-effective option in almost all prenatal screening strategies is the option that includes all targeted additional conditions. In the strategies where NIPS is used as first-tier testing, the cost per additional case detected by adding all possible additional anomalies to a programme that currently targets only common trisomies is $C25 710 (95% CI $C25 489 to $C25 934) for massively parallel shotgun sequencing and $C57 711 (95% CI $C57 141 to $C58 292) for targeted massively parallel sequencing, respectively. The acceptability curves show that at a willingness-to-pay of $C50 000 per one additional case detected, the expansion of NIPS-based methods for the detection of all possible additional conditions has a 90% probability of being cost-effective.

CONCLUSION

From an economic perspective, in strategies that use NIPS as a first-tier screening test, expanding the programmes to detect any considered chromosomal anomalies other than the three common trisomies would be cost-effective. However, the potential expansion of prenatal screening programmes also requires consideration of societal issues, including ethical ones.

The impact of working hours on pregnancy intention in childbearing-age women in Korea, the country with the world's lowest fertility rate

This study aimed to assess factors affecting pregnancy intention among women of reproductive age in Korea. We analyzed data from the Korean National Health and Nutrition Examination Survey (KNHANES), a population-based survey that included 22,731 women aged 15-49. As age was associated with birth year and was found to be a confounding factor in the analysis of participants' characteristics, we used propensity score matching to assess the characteristics of pregnant women compared with non-pregnant women of the same age and birth year. We also employed the XGBoost machine learning model to identify the most important factors related to pregnancy intentions. Our feature importance analysis showed that weekly working hours were the most significant factor affecting pregnancy intentions. Additionally, we performed cluster analysis and logistic regression models to determine optimal weekly working hours. Cluster analysis identified participants into three distinct groups based on their characteristics, indicating that the group with an average of 34.4±12.9 hours per week had the highest likelihood of becoming pregnant. Logistic regression was used to analyze the odds of pregnancy for every 5-hour increase in weekly working hours. The results of logistic regression indicated that women who worked between 35-45 hours per week had higher odds of pregnancy, with significant odds ratios of 2.009 (95% confidence interval: 1.581-2.547, p < .001) for 40-45 hours per week and 1.450 (95% confidence interval: 1.001-2.040, p < .05) for 35-40 hours per week, compared to women working other hours. In Korea, the standard workweek is typically 40 hours; however, Koreans often work considerably longer hours, with the second-highest number of working hours among OECD countries in 2022. This study suggests that strict monitoring of working hours and expansion of telecommuting for childbearing-age women are important factors in increasing the fertility rate in Korea.

Cytogenetic status of patients with congenital malformations or suspected chromosomal abnormalities in Turkey: a comprehensive cytogenetic survey of 11,420 patients

Cytogenetic analysis is helpful in diagnostic workup of patients having prenatal or early postnatal medical problems and provides a basis for genetic counseling or deciding on clinical treatment options. Chromosomal abnormalities (CAs) constitute one of the most important category of genetic defects which have the potential to cause irreversible disorders. In this study, chromosome analysis results of 11,420 patients having congenital malformations or suspected of having chromosomal abnormalities, who were referred to Çukurova University Research and Training Hospital Cytogenetic Laboratory over a 16-year period, were investigated, retrospectively. Of all patients analyzed, CAs were found in 1768 cases, accounting for 15.5% of all cases. It was observed that 1175 (15.5%) of CAs were numerical (10.3%) and 593 (5.2%) were structural chromosome abnormalities. Among numerical CAs, Down syndrome (DS), Turner syndrome (TS) and Klinefelter syndrome (KS) constituted common categories which were observed in 7, 1.1 and 0.9% of all cases, respectively. Among the structural CAs, translocations, inversions, fragilities, deletions,, and others were the most common categories and constituted 2.2, 0.9, 0.9, 0.7, 0.3, and 0.3% of all cases, respectively. The sex ratio (male/female) of all cases was 1.01 and of DS cases was 1.6. Our results further confirmed that cytogenetic analysis is necessary in terms of making definite diagnosis of genetic disorders, providing proper genetic counseling and clinical treatment, assessing the recurrence risk, and preventing the hereditary genetic diseases and disorders. Besides, such studies will greatly assist in constituting national and international databases or records of genetic disorders.

Prenatal cytogenetic diagnosis: results obtained in the specialized laboratory of Clínica Universitaria Colombia from 2013 to 2019

OBJECTIVE

Prenatal cytogenetic evaluation is a key tool for identifying alterations in pregnant women with high risk for fetal chromosomal abnormalities (CA). In Colombia, there are not large-scale reports about the prevalence and pattern of CA in prenatal cytogenetic analysis.

METHOD

A descriptive study was performed from registers of prenatal cytogenetic analysis on amniotic fluid (AF), chorionic villus biopsy (CVS), and fetal blood (FB) samples sent to the specialized laboratory of the Clínica Universitaria Colombia between 2013 and 2019.

RESULTS

The prevalence of CA was 20.9%. The trisomies 21, 18, 13, and monosomy X were the most frequent aneuploidies, and the derivative chromosomes were the most frequent structural abnormalities. Although the rate of CA was higher in women over the age of 35 years old; monosomy X, unbalanced rearrangements, and microduplications were associated with the group of women under the age of 35 (p < .05). Trisomies 21 and 18 were the most common aneuploidies identified by FISH and were found to be altered in 52% of the aCGH studies. Ultrasonographic markers associated with CA were the most frequent clinical indication.

CONCLUSION

In Colombia, the invasive prenatal cytogenetic analysis continues being an important diagnostic tool available for pregnant women with high risk for fetal CA.

Management of Pregnancy in Women of Advanced Maternal Age: Improving Outcomes for Mother and Baby

Pregnancy at advanced maternal age (age >35 years old) is considered a risk factor for adverse maternal and perinatal outcomes. Yet, pregnancies of advanced maternal age have become more prevalent over the last few decades. Possible maternal complications of pregnancy at age 35 or older include increased risk of spontaneous miscarriage, preterm labor, gestational diabetes mellitus, pre-eclampsia, stillbirth, chromosomal abnormalities, and cesarean delivery. Possible adverse fetal outcomes include infants small for gestational age and intrauterine growth restrictions, low Apgar score, admission to neonatal intensive care units, and an autism spectrum disorder. This paper aims to present an up-to-date review of the literature, summarizing the most current studies and implications for the management of pregnancy of advanced maternal age.

PGT-A: who and when? Α systematic review and network meta-analysis of RCTs

PURPOSE

Wide controversy is still ongoing regarding efficiency of preimplantation genetic testing for aneuploidy (PGT-A). This systematic review and meta-analysis, aims to identify the patient age group that benefits from PGT-A and the best day to biopsy.

METHODS

A systematic search of the literature was performed on MEDLINE/PubMed, Embase and Cochrane Central Library up to May 2020. Eleven randomized controlled trials employing PGT-A with comprehensive chromosomal screening (CCS) on Day-3 or Day-5 were eligible.

RESULTS

PGT-A did not improve live-birth rates (LBR) per patient in the general population (RR:1.11; 95%CI:0.87-1.42; n=1513; I2=75%). However, PGT-A lowered miscarriage rate in the general population (RR:0.45; 95%CI:0.25-0.80; n=912; I2=49%). Interestingly, the cumulative LBR per patient was improved by PGT-A (RR:1.36; 95%CI:1.13-1.64; n=580; I2=12%). When performing an age-subgroup analysis PGT-A improved LBR in women over the age of 35 (RR:1.29; 95%CI:1.05-1.60; n=692; I2=0%), whereas it appeared to be ineffective in younger women (RR:0.92; 95%CI:0.62-1.39; n=666; I2=75%). Regarding optimal timing, only day-5 biopsy practice presented with improved LBR per ET (RR: 1.37; 95% CI: 1.03-1.82; I2=72%).

CONCLUSION

PGT-A did not improve clinical outcomes for the general population, however PGT-A improved live-birth rates strictly when performed on blastocyst stage embryos of women over the 35-year-old mark.

The correlation between maternal age and fetal sex chromosome aneuploidies: a 8-year single institution experience in China

Background

Although a few studies have investigated a possible association between maternal age and fetal sex chromosome aneuploidies (SCAs), most of these studies were limited to advanced maternal age (AMA) women and the results were conflicting. This study aimed to investigate the correlation between maternal age and common fetal SCAs (including 45,X, 47,XXY, 47,XXX and 47,XYY) in pregnant women of different ages that not only limited to AMA women. We retrospectively investigated a 8-year experience of prenatal diagnosis for fetal chromosome aberrations by second-trimester amniocentesis at a university teaching hospital in China. 20,409 amniotic fluid specimens collected at 19–22⁺⁶ gestational weeks were included in this study. The women were categorized into five age groups (≤ 23, 24–28, 29–33, 34–38, 39⁺ years) based on maternal age at the time of amniocentesis and entered as a categorical variable in all samples. The correlation between fetal SCAs and maternal age was determined using the logistic regression analysis. A chi-square test was performed to compare the incidence of fetal SCAs among age groups.

Results

A total of 179 cases of fetal SCAs were detected, and the incidence was 8.77‰ (about 1/114). The incidence of fetal SCAs increased significantly with advancing maternal age (SE, 0.014; odds ratio, 1.044; P = 0.002). Specifically, the incidence of 45,X (SE, 0.037; odds ratio, 0.916; P = 0.017) and 47,XXY (SE, 0.024; odds ratio, 1.127; P = 0.000) had significant correlation with maternal age, while the incidence of 47,XXX and 47,XYY had no correlation with maternal age (P = 0.473; P = 0.272, respectively). The incidence of fetal SCAs was also significantly different among age groups (χ² = 10.197, P = 0.037 < 0.05), from 5.81 per 1000 fetuses at the 24–28 years to 10.92 per 1000 at the 39⁺ years.

Conclusions

Maternal age was ascertained to be a strong risk factor for fetal SCAs.

Clinical Application of Chromosomal Microarray Analysis in Pregnant Women with Advanced Maternal Age and Fetuses with Ultrasonographic Soft Markers

Background

In pregnant women with advanced maternal age (AMA) and fetuses with ultrasonographic (USG) soft markers it is always challenging to decide whether to implement chromosomal microarray analysis (CMA) or not. It is unclear whether CMA should be used in the fetuses with isolated USG soft markers, and there is still a lack of extensive sample research.

Material/Methods

We enrolled 1521 cases in our research and divided them into 3 groups as follows: pregnant women with isolated AMA (group 1, n=633), pregnant women whose fetuses had isolated USG soft markers (group 2, n=750), and pregnant women with AMA whose fetuses had isolated USG soft markers (group 3, n=138). All pregnant women underwent prenatal ultrasound and amniocentesis, and fetal cells in the amniotic fluid were used for genetic analysis of CMA. All participants signed a written informed consent prior to CMA.

Results

Abnormal findings were detected by CMA in 330 (21.70%) fetuses, including 37 (2.43%) clinically significant copy number variations (CNVs), 52 (3.42%) benign or likely benign CNVs, and 240 (15.78%) variants of unknown significance. The frequency of clinically significant CNVs in group 1 and group 2 were significantly lower than that in group 3 (2.37% and 2.0% vs 5.07%, P<0.01). More than a half (59.46%, 22/37) of the pregnant women decided to continue their pregnancy despite having a fetus diagnosed with clinically significant CNV.

Conclusions

CMA can increase the diagnostic yield of fetal chromosomal abnormality for pregnant women with isolated AMA or/and their fetuses had isolated USG soft markers.

Multi-institutional experience of genetic diagnosis in Ecuador: National registry of chromosome alterations and polymorphisms

BACKGROUND

Detection of chromosomal abnormalities is crucial in various medical areas; to diagnose birth defects, genetic disorders, and infertility, among other complex phenotypes, in individuals across a wide range of ages. Hence, the present study wants to contribute to the knowledge of type and frequency of chromosomal alterations and polymorphisms in Ecuador.

METHODS

Cytogenetic registers from different Ecuadorian provinces have been merged and analyzed to construct an open-access national registry of chromosome alterations and polymorphisms.

RESULTS

Of 28,806 karyotypes analyzed, 6,008 (20.9%) exhibited alterations. Down syndrome was the most frequent autosome alteration (88.28%), followed by Turner syndrome (60.50%), a gonosome aneuploidy. A recurrent high percentage of Down syndrome mosaicism (7.45%) reported here, as well as by previous Ecuadorian preliminary registries, could be associated with geographic location and admixed ancestral composition. Translocations (2.46%) and polymorphisms (7.84%) were not as numerous as autosomopathies (64.33%) and gonosomopathies (25.37%). Complementary to conventional cytogenetics tests, molecular tools have allowed identification of submicroscopic alterations regions or candidate genes which can be possibly implicated in patients' symptoms and phenotypes.

CONCLUSION

The Ecuadorian National Registry of Chromosome Alterations and Polymorphisms provides a baseline to better understand chromosomal abnormalities in Ecuador and therefore their clinical management and awareness. This data will guide public policy makers to promote and financially support cytogenetic and genetic testing.

Relationship between first trimester nuchal septations and chromosomal anomalies

OBJECTIVES

This study aimed to evaluate the association of nuchal septations with chromosomal anomalies during the first trimester of pregnancy.

METHODS

A total of 281 patients who were diagnosed to have elevated nuchal translucency (NT > 3 mm) or nuchal septations during the first trimester from Jan. 2014 to Dec. 2016 were included. These patients were divided into three groups: 1) patients with NT thickness between 3 and 5 mm and without nuchal septations (NT 3-5 mm group, n = 124), 2) patients with NT thickness > 5 mm and without nuchal septations (NT > 5 mm group, n = 96), and 3) patients with nuchal septations (NS group, n = 61).

RESULTS

The rate of chromosomal abnormalities was significantly higher for patients in NS group compared to those in the NT 3-5 mm group (P < .01) and NT > 5 mm group (P < .01). After controlling for maternal age, maternal BMI, ethnicity and crown-rump length, nuchal septations were reported to be significantly associated with a higher risk of chromosomal anomalies compared with NT 3-5 mm (OR = 4.97; 95% CI: 2.76-10.77; P < .01) and NT > 5 mm (OR = 3.82; 95% CI: 1.87-7.21; P < .01) (P < .01).

CONCLUSIONS

Measurement of nuchal septations during the first trimester of pregnancy proves to be a useful ultrasound prognostic indicator of chromosomal anomalies.

Risk factors associated with congenital defects that alter hearing or vision in children born in the city of Bogotá between 2002 and 2016

INTRODUCTION

Congenital defects affecting the auditory and visual capacity of newborns represent a public health problem as they result in substantial disability, directly impacting the quality of life of newborns and their families.

OBJECTIVE

To evaluate risk factors associated with congenital defects that alter hearing or vision in newborns in the city of Bogotá between 2002 and 2016.

METHOD

Data from the Bogotá Birth Defects Surveillance and Follow-up Program was used, which consolidated data regarding 167 ECLAMC study (Estudio Colaborativo Latino Americano de Malformaciones Congénitas, in spanish) variables in a case-control design to identify risk factors for birth defects after parents provided signed informed consent. Cases were defined as any newborn (alive or stillborn) with a weight greater than 500 g with any visual or hearing abnormality. Controls were defined as newborn in the same hospital and month with no birth defects. Groups were formed according to the case presentation as follows: isolated eye anomaly, isolated ear anomaly, polymalformative, syndromic, and teratogenic.

RESULTS

In total, 402,657 births were reviewed, of which 968 cases had some congenital defects that alter hearing or vision. An association was found between the presence of defects and prematurity, as well as between syndromic cases and increasing maternal age. When comparing cases and controls with the risk of having a birth defect, multiparity had an odds ratio (OR) of 1.47 (95% CI: 1.27-1.71), acute respiratory infection had an OR of 2.41 (95% CI: 1.04-5.58), low maternal education level had an OR of 1.34 (95% CI:1.10-1.62), low paternal education had an OR of 1.42, (95% CI:1.17-1.73), manual labor in the maternal occupation had an OR of 1.31 (95% CI:1.03-1.67), and a history of congenital anomalies in the family had an OR of 1.55 (95% CI:1.19-2.00).

CONCLUSION

This research allowed the identification of epidemiological data and significant risk factors for congenital defects that alter hearing or vision in the population of Bogotá.

Analysis of prenatal diagnosis before and after implementation of the two-child policy in northeastern China

The universal two-child policy has now been fully implemented in China. This change requires adaptations to maternal care and childcare systems, but the features of prenatal diagnosis before and after implementation of the policy have not been reported.We conducted a retrospective study of 6736 prenatal cytogenetic diagnoses performed on amniotic fluid cells over a 4-year period, including 2 years before and after implementation of the second child policy. Amniotic fluid cells collected through amniocentesis were cultured, harvested, and stained for chromosome analysis using standard laboratory protocols.The study included 3222 pregnant women referred before implementation of the policy, which we used as a control group, and 3514 pregnant women referred after policy implementation as an investigational study group. There were significantly fewer pregnant women aged <25 years in the investigational group than in the control group (P < .001). There were no significant between-group differences for other pregnant women aged >31 years and 27-28 years old (P > .05). A total of 358 cases with chromosomal abnormalities were diagnosed, including 129 (4%, 129/3222) in the control group which was significantly lower than the 229 (6.5%, 229/3514) in the study group (P < .001). In particular, significantly more trisomy 21 cases were observed in the study group than in the control group (120 vs 59). More pregnant women underwent non-invasive prenatal testing (NIPT) in the study group (46%) than in the control group (20%). In the study group, the average age of pregnant women who underwent NIPT was significantly higher than that of women who did not receive NIPT (P < .05). However, there were no significant between-group differences for the control group (P > .05).The number of cases with chromosomal abnormalities increased in northeastern China in the 2 years after implementation of the two-child policy. The number of pregnant women of advanced maternal age did not increase significantly, perhaps because of the widespread application of NIPT. However, the number of fetuses with Down syndrome increased significantly, suggesting that prenatal screening and diagnosis should be strengthened.

Multilevel regression modeling for aneuploidy classification and physical separation of maternal cell contamination facilitates the QF-PCR based analysis of common fetal aneuploidies

Background

The quantitative fluorescent polymerase chain reaction (QF-PCR) has proven to be a reliable method for detection of common fetal chromosomal aneuploidies. However, there are some technical shortcomings, such as uncertainty of aneuploidy determination when the short tandem repeats (STR) height ratio is unusual due to a large size difference between alleles or failure due to the presence of maternal cell contamination (MCC). The aim of our study is to facilitate the implementation of the QF-PCR as a rapid diagnostic test for common fetal aneuploidies.

Methods

Here, we describe an in-house one-tube multiplex QF-PCR method including 20 PCR markers (15 STR markers and 5 fixed size) for rapid prenatal diagnosis of chromosome 13, 18, 21, X and Y aneuploidies. In order to improve the aneuploidy classification of a given diallelic STR marker, we have employed a multilevel logistic regression analysis using "height-ratio" and "allele-size-difference" as fixed effects and "marker" as a random effect. We employed two regression models, one for the 2:1 height ratio (n = 48 genotypes) and another for the 1:2 height ratio (n = 41 genotypes) of the trisomic diallelic markers while using the same 9015 genotypes with normal 1:1 height ratio in both models. Furthermore, we have described a simple procedure for the treatment of the MCC, prior DNA isolation and QF-PCR analysis.

Results

For both models, we have achieved 100% specificity for the marker aneuploidy classification as compared to 98.60% (2:1 ratio) and 98.04% (1:2 ratio) specificity when using only the height ratio for classification. Treatment of the MCC enables a successful diagnosis rate of 76% among truly contaminated amniotic fluids.

Conclusions

Adjustment for the allele size difference and marker type improves the STR aneuploidy classification, which, complemented with appropriate treatment of contaminated amniotic fluids, eliminates sample re-testing and reinforces the robustness of the QF-PCR method for prenatal testing.

The assessment of combined karyotype analysis and chromosomal microarray in pregnant women of advanced maternal age: a multicenter study

Background

Retrospectively analyzed the results of prenatal diagnosis and hoped to provide scientific clinical guidance of prenatal screening and diagnosis for the women in advanced maternal age (AMA).

Methods

In total, 4,224 women of AMA who accepted prenatal diagnosis by amniocentesis (AC) from two prenatal diagnosis centers were recruited for this study. After genetic counseling and informed consent, 3,475 women received karyotype analysis only, 703 were examined by both karyotype analysis and chromosomal microarray (CMA), while 46 cases selected CMA only. Both centers used the same detection platform, experimental scheme, and quality control standards.

Results

A total of 164 women with chromosomal abnormal results were found, the abnormality rate was 3.88% (164/4,224). Among them, 145 (3.4%, 145/4,224) cases were detected as abnormal chromosome number, 19 cases (0.4%, 19/4,224) as abnormal chromosome structure. Compared with simple AMA women, the abnormality rate was significantly increased in the AMA women who combined with other indications, particularly in number abnormalities (22.5% vs. 1.0%, P<0.001). Forty-eight copy number variations (CNVs) were detected, moreover 10 cases (0.24%, 10/4,224) were proved as pathogenic or likely pathogenic CNVs. With the CMA technology, the rate of additional abnormalities with clinical significance was 1.42% (10/703). Chromosome number abnormalities significantly increased with age (P<0.001), while there were no such trends in chromosomal structural abnormalities (P=0.624).

Conclusions

About 3.88% fetuses of AMA women had chromosomal abnormalities, the abnormality rate increased with their age. The application of CMA could increase the diagnostic rate by about 1.4% for AMA women, and greatly reduce their tension.

Risk of Adverse Pregnancy Outcomes at Advanced Maternal Age

OBJECTIVE

To study the possible associations between advanced maternal age and risk of selected adverse pregnancy outcomes.

METHODS

The study used a nationwide cohort of 369,516 singleton pregnancies in Denmark followed from 11-14 weeks of gestation to delivery or termination of pregnancy. Pregnant women aged 35 years or older were divided into two advanced maternal age groups, 35-39 years and 40 years or older, and compared with pregnant women aged 20-34 years. Adverse pregnancy outcomes were chromosomal abnormalities, congenital malformations, miscarriage, stillbirth, and birth before 34 weeks of gestation. Multivariable logistic regression analyses were performed to investigate associations between advanced maternal age and adverse pregnancy outcomes. Furthermore, a risk prediction model for a composite adverse pregnancy outcome was made with prespecified predicting factors.

RESULTS

Among the pregnant women aged 40 years or older, 10.82% experienced one or more of the selected adverse pregnancy outcomes compared with 5.46% of pregnant women aged 20-34 years (odds ratio [OR] 2.02, 99.8% CI 1.78-2.29). When pregnant women 40 years or older were compared with women aged 20-34 years, they had a higher risk of chromosomal abnormalities (3.83% vs 0.56%, OR 7.44 [CI 5.93-9.34]), miscarriage (1.68% vs 0.42%, OR 3.10 [CI 2.19-4.38]), and birth before 34 weeks of gestation (2.01% vs 1.21%, OR 1.66 [CI 1.23-2.24]), but no increased risk of congenital malformations and stillbirth. The risk prediction chart showed that advanced maternal age, use of assisted reproductive technology, nulliparous pregnancy, smoking during pregnancy, and obesity increased the absolute predictive risk of an adverse pregnancy outcome.

CONCLUSION

Women older than 40 years have a higher risk of chromosomal abnormalities, miscarriage, and birth before 34 weeks of gestation than younger women and should be monitored accordingly. No increased risk was observed for stillbirth and other congenital malformations. Several factors increase the risk of adverse pregnancy outcomes, but advanced maternal age drives a high proportion of the total risk score.

Sexual Identity Disorder and Psychosis in Klinefelter Syndrome: A Synthesis of Literature and a Case Report

Klinefelter syndrome (KS) 47, XXY is the most frequent chromosomal abnormality causing hypogonadism in humans. This chromosomal abnormality of number in its classical form called homogeneous (supernumerary X) is generally the result of a meiosis accident. Several studies have suggested that individuals with KS are at greater risk of developing various psychiatric disorders, including depression and schizophrenia. The diagnosis is made based on subnormal testosterone with high pituitary gonadotropins and confirmed by determining the karyotype on a blood simple. We did a literature review using an electronic search in three databases: Pubmed/MEDLINE, Google Scholar, and PsychInfo. We found that since 1989, seven case reports with KS and mental disorders with similar and different characteristics of our case illustration of a patient with KS and psychosis were published.

Change in rates of prenatal tests for chromosomal abnormality over a 12-year period in women of advanced maternal age

Objective

In 2007, the American College of Obstetricians and Gynecologists (ACOG) recommended that all pregnant women be offered screening or diagnostic tests for chromosomal abnormalities regardless of their age. Noninvasive prenatal testing (NIPT) for common chromosomal aneuploidies was introduced as a screening test in case of high-risk pregnancies. We assessed the rates of prenatal tests in women aged 35 years and older.

Methods

A retrospective study was conducted to compare the rates of amniocentesis, chorionic villus sampling (CVS), serum screening, and NIPT from January 2005 through March 2017 in women aged 35 years and older. We divided the initial 12 months after NIPT introduction into 4-month intervals, beginning in April 2016 through March 2017.

Results

The rates of amniocentesis were 56% before the ACOG statement, 38% between the ACOG statement and NIPT introduction, and 10% after NIPT introduction (P=0.001). The rates of CVS during the same periods were 0.5%, 2.1%, and 4.3% (P=0.016), respectively. The rates of serum screening were 44.2%, 61.3%, and 55.1% (P=0.049), respectively. During the 3 quarters after NIPT introduction, the rates of amniocentesis were 16.2%, 12.3%, and 7.3% (P=0.002), respectively; the rates of serum screening were 62%, 54%, and 46% (P=0.03), respectively; and the rates of NIPT were 19.9%, 30.3%, and 39.5% (P=0.007), respectively. The rates of CVS over the same periods were not significantly different.

Conclusion

The ACOG statement and NIPT introduction significantly decreased the rate of amniocentesis in women of advanced maternal age. NIPT also reduced the rate of serum screening.

Ignorance is bliss: women's knowledge regarding age-related pregnancy risks

Pregnancy risks rise with age and the average age of first time mothers is rising. This study aimed to assess women's actual knowledge and their perceived knowledge of pregnancy complications relating to advanced maternal age. A cross-sectional survey was administered to primiparous women measuring demographics, knowledge of age-related pregnancy risks, previous counselling and health literacy. Of the 218 women surveyed, the mean knowledge score was not significantly different for women <35 years of age compared to women ≥35 years of age (p = .09). Although there was no difference in knowledge between the two groups, women ≥35 years of age perceived themselves to be more knowledgeable than those under 35 (p < .01). The majority of women (67%) wanted further counselling on this topic and indicated a preference for their doctor to counsel them (76%). Women require counselling informing them of their increased risk of complications if they begin childbearing at older ages. Impact statement What is already known on this subject: The average age of first time mothers is rising worldwide. Pregnancy risks rise with age, especially in first time mothers. Previous studies have shown that knowledge of age-related pregnancy risks correlate with educational level and health literacy. What the results of this study add: This study supports those findings and also demonstrates that perceived knowledge does not correlate with measured knowledge of age-related pregnancy risks. Women ≥35 years of age (higher-risk women) are no more knowledgeable than their younger counterparts though they perceive themselves to be better informed. Greater education regarding these risks may allow women to mitigate some of these risks through lifestyle and diet alteration and will prepare women for what to expect if these risks and complications occur. The majority of women in this study seek pregnancy information on the internet, but desire further counselling from their doctors regarding age-related pregnancy risks. What the implications are of these findings for clinical practice and/or further research: Given these results, physicians must consider making greater efforts to counsel women about pregnancy risks in advanced maternal age and tailor these conversations to suit the educational level and health literacy of each individual patient.

Chromosomal abnormalities: subgroup analysis by maternal age and perinatal features in zhejiang province of China, 2011-2015

BACKGROUND

Recently, the prevalence of chromosomal abnormalities (CA) increased as the increasing proportion of mothers with advanced age. We aimed to explore the prevalence of CA in relation to maternal age and perinatal features.

METHODS

A retrospective study was performed based on provincial birth defects surveillance data. The relative risk (RR) and 95% confidence interval (CI) were used to calculate maternal age-specific rates of CA. Socio-demographic characteristics of mothers and perinatal features were listed.

RESULTS

The total prevalence of CA was 6.38 per 10,000 births, which increased per 10,000 births linearly from 4.02 in 2011 to 9.13 in 2015 (x ²_line-trend =52.69, p < 0.001). During this period, the prevalence for CA per 10,000 births among women over 35 years old increased from 15.34 in 2011 to 33.82 in 2015 (x ²_line-trend =115121.6, p < 0.001). The RR for overall CA, trisomy 21(T21), trisomy 18(T18) and others in mothers 35 years or older were 6.64 (95% CI 5.55 ~ 7.93), 6.83 (95% CI 5.63 ~ 8.30), 4.06 (95% CI 2.09 ~ 7.90) and 7.54 (95% CI 4.02 ~ 14.11) respectively in comparison to mothers aged 25-29 years old. The stillbirths rate for total CA was 76.45%. T21 and T18 were strongly associated with multiple anomalies, especially congenital heart abnormalities.

CONCLUSIONS

The prevalence of CA increased as maternal age increased. Cases with CA were associated with other congenital defects and high mortality risk.

Maternal Age-Specific Rates for Trisomy 21 and Common Autosomal Trisomies in Fetuses from a Single Diagnostic Center in Thailand

To provide maternal age-specific rates for trisomy 21 (T21) and common autosomal trisomies (including trisomies 21, 18 and 13) in fetuses. We retrospectively reviewed prenatal cytogenetic results obtained between 1990 and 2009 in Songklanagarind Hospital, a university teaching hospital, in southern Thailand. Maternal age-specific rates of T21 and common autosomal trisomies were established using different regression models, from which only the fittest models were used for the study. A total of 17,819 records were included in the statistical analysis. The fittest models for predicting rates of T21 and common autosomal trisomies were regression models with 2 parameters (Age and Age²). The rate of T21 ranged between 2.67 per 1,000 fetuses at the age of 34 and 71.06 per 1,000 at the age of 48. The rate of common autosomal trisomies ranged between 4.54 per 1,000 and 99.65 per 1,000 at the same ages. This report provides the first maternal age-specific rates for T21 and common autosomal trisomies fetuses in a Southeast Asian population and the largest case number of fetuses have ever been reported in Asians.

Population-Based Study of Prevalence of Cleft Lip/Palate in Southern Thailand

Introduction

Oral cleft is a common craniofacial birth defect that leads to long-lasting adverse outcomes. In Thailand, there have been two studies of the prevalence of oral clefts using data from university hospitals during 1969 through 1978 and 1988 through 1999, which found prevalence rates of 1.23 and 1.22 per 1000 live births, respectively.

Objective

The primary outcome was to assess the prevalence of oral clefts from the birth defects registry during 2009 through 2013 in three provinces in southern Thailand. The secondary outcomes were to correlate the risk of oral cleft and maternal age.

Design

Population-based study.

Setting

Four hundred sixty-seven hospitals in three provinces in southern Thailand.

Participants

Oral cleft cases and maternal data—including live births, stillbirths, and termination of pregnancy following a prenatal diagnosis—were collected from the birth defects registry.

Results

Of the total 186,393 births, there were 269 oral cleft cases, giving an average prevalence of 1.44 per 1000 births (95% CI, 1.22-1.63). The most common cleft type was cleft lip and palate (45.0%), followed by cleft palate (29.0%), with 15.6% syndromic cleft. The mean maternal age was 28.0 ± 6.4 years. There were no differences in prevalence of oral clefts among the different maternal age groups. However, advanced maternal age 35+ years was associated with syndromic cleft children.

Conclusions

The prevalence of oral clefts was 1.44 per 1000 live births, with 15% of cases having an associated congenital anomaly or a recognized syndrome. Increased maternal age was associated with a higher prevalence of syndromic cleft.

Delineating the Mosaic Trisomy 15 Phenotype Using a Serendipitous Mechanism as a Clue

Parental balanced translocation is one of the traditional indications for invasive prenatal diagnosis. Usually, the diagnostic process is straightforward. Sometimes, however, results are not entirely clear and may reveal unexpected biological processes. We performed chorionic villi sampling for a paternal 8;15 reciprocal translocation in the sixth pregnancy of a Caucasian woman. Cytogenetic analysis of chorionic villi, after both short- and long-term cultures, revealed the presence of the same rearrangement found in the father as well as a trisomy 15. Surprisingly, the trisomy, which was initially expected to derive from aberrant segregation during paternal meiosis, resulted instead from maternal nondisjunction. Although a sonogram of the fetus appeared to be normal, follow-up amniocentesis demonstrated a low-level mosaic trisomy 15 in cells extracted from the amniotic fluid, while 10% of cells from fetal tissues sampled after termination of the pregnancy were also found to be trisomic. Fetal autopsy showed dysmorphic features, confirming the diagnosis of mosaic trisomy 15 and enabled deeper insight into the prenatal phenotype of this rare condition.

Male biological clock: a critical analysis of advanced paternal age

Extensive research defines the impact of advanced maternal age on couples' fecundity and reproductive outcomes, but significantly less research has been focused on understanding the impact of advanced paternal age. Yet it is increasingly common for couples at advanced ages to conceive children. Limited research suggests that the importance of paternal age is significantly less than that of maternal age, but advanced age of the father is implicated in a variety of conditions affecting the offspring. This review examines three aspects of advanced paternal age: the potential problems with conception and pregnancy that couples with advanced paternal age may encounter, the concept of discussing a limit to paternal age in a clinical setting, and the risks of diseases associated with advanced paternal age. As paternal age increases, it presents no absolute barrier to conception, but it does present greater risks and complications. The current body of knowledge does not justify dissuading older men from trying to initiate a pregnancy, but the medical community must do a better job of communicating to couples the current understanding of the risks of conception with advanced paternal age.