Randomized trial of advice from healthcare professionals to eliminate constriction by maternal clothing on the trunk to prevent preterm birth and improve health status.

AIM: Women's clothing during pregnancy may influence perinatal outcomes. A preliminary study suggested that midwives' advice to avoid wearing tight clothing during pregnancy may reduce the risk of preterm delivery. We examined the effects of such advice to pregnant women on the risk of preterm birth and health status during pregnancy. METHODS: An open-label evaluator-blinded randomized controlled trial was conducted at the National Centre for Child Health and Development in Tokyo, Japan. Normal pregnant women were randomly assigned to receive constrictive clothing elimination care or standard care at 20 weeks gestation. The control group was issued leaflets concerning anemia prevention at entry and skin care at 30 weeks' gestation, along with a brief explanation and answers to questions by midwives as standard care. The intervention group received advice from midwives concerning avoiding constrictive clothing in addition to standard care. The primary outcome was the incidence of preterm birth (<37 weeks). The secondary outcomes were 12 indicators related to preterm delivery or health status. RESULTS: Among 624 randomly assigned women, 599 (intervention group, n = 306; control group, n = 293) completed the study between February 2015 and August 2016. The incidence of preterm birth in the intervention and control groups was 4.2% (13/306) and 5.1% (15/293), respectively (p = 0.614). There were no significant differences regarding any secondary outcomes, including obstetric outcomes and physical/mental indicators, during pregnancy. CONCLUSIONS: Advice from midwives to avoid constrictive clothing during pregnancy did not influence the incidence of preterm birth or maternal health status. TRIAL REGISTRATION: UMIN000016853 (March 30, 2015).

The secretion and metabolism of cumulus cells support fertilization in the bovine model.

The cumulus oophorus is a structure that surrounds the mammalian egg and plays a key role in fertilization. However, very little is known with regards to how secretions from the cumulus cells can specifically promote fertilization. We hypothesized that secretions from bovine cumulus cells, and the reduction of oxygen stress by metabolic change, would enhance the fertilization capacity of sperm during in vitro fertilization (IVF) procedures. To prove our hypothesis, sperm were pre-incubated in chemically defined capacitation media containing methyl-beta-cyclodextrin and used to inseminate cumulus cell oocyte complexes, or denuded oocytes, with some components. While sperm capacitation was induced in capacitation media, fertilization was impeded by the removal of cumulus cells from cumulus cell oocyte complexes. Secretions from cumulus cells promoted the formation of two pronuclei via a filter and the fertilization of denuded oocytes was dramatically enhanced with hyaluronate, low oxygen concentration, or progesterone in fertilization media (P < 0.05). This demonstrates that these factors-maintained sperm motility and capacitation or enhanced the hyper-activation of capacitated sperm (P < 0.05). We conclude that cumulus cells secrete progesterone, hyaluronate and undergo metabolic events to reduce oxidative stress in fertilization media. These phenomenons help to improve the fertilization capacity of sperm. We believe that this study makes a significant contribution to our understanding of the function of cumulus cells during fertilization in animals and humans.

Diazoxide during pregnancy and lactation: drug levels in maternal serum, cord blood, breast milk, and infant serum: a case report.

Safety information on diazoxide for pregnant and lactating women with hypoglycemia is limited. In this case report, we assessed diazoxide concentrations in maternal and infant blood, cord blood, and breast milk. We described a 30-year-old pregnant woman diagnosed with hypoglycemia due to nesidioblastosis at 4 months of age. Before becoming pregnant, she was treated with oral diazoxide (75-375 mg). All medications were discontinued after she was discovered to be pregnant. During gestational week 25, diazoxide treatment was resumed at 150-175 mg daily for repeated hypoglycemic episodes. Diazoxide administration was continued in combination with diet treatment until delivery. Glucose levels were well controlled. During gestational week 40, a male infant weighing 3069 g was delivered via spontaneous vaginal delivery with no pregnancy or neonatal complications. Diazoxide concentrations detected in maternal serum at 2.5-11.6 h after oral treatment ranged from 12.4 to 32.7 µg/mL. In cord blood, the diazoxide concentration was 18.5 µg/mL at 7.2 h after the last dose. During lactation, no hypoglycemia or hyperglycemia was observed. The approximate calculated ratio of diazoxide in breast milk and maternal serum was 0.09. The calculated daily infant dose was 0.47 mg/kg/day. The relative infant dose via breast milk ranged from 3.1% to 5.9%. Diazoxide transferred from maternal blood to the fetus across the placenta. It also transferred into breast milk, but there were no harmful effects on the infant.

Periconceptional folic acid intake and disturbing factors: A single-center study in Japan.

We investigated folic acid (FA) intake and disturbing factors in pregnant women who visited our center in 2017. Among 1531 pregnant women, 45.1% of women initiated FA supplementation before pregnancy. The risk of failure of supplementation was significantly lower among women of ≥35 (adjusted odds ratio [aOR] 0.43) and 30-34 years of age (aOR: 0.59) in comparison to women of <30 years of age, and among those conceived with timing/artificial insemination of husband (aOR 0.47) and in vitro fertilization/intracytoplasmic sperm injection (aOR 0.32) in comparison to those conceived naturally. The risk among those with 1 (aOR 1.44) or ≥2 previous deliveries (aOR 2.75) was significantly higher in comparison to nulliparous women. Young, multiparous women, and those with natural conception should be targeted to promote preconceptional FA intake.

Improved library preparation protocols for amplicon sequencing-based noninvasive fetal genotyping for RHD-positive D antigen-negative alleles.

OBJECTIVE: We aimed to simplify our fetal RHD genotyping protocol by changing the method to attach Illumina's sequencing adaptors to PCR products from the ligation-based method to a PCR-based method, and to improve its reliability and robustness by introducing unique molecular indexes, which allow us to count the numbers of DNA fragments used as PCR templates and to minimize the effects of PCR and sequencing errors. RESULTS: Both of the newly established protocols reduced time and cost compared with our conventional protocol. Removal of PCR duplicates using UMIs reduced the frequencies of erroneously mapped sequences reads likely generated by PCR and sequencing errors. The modified protocols will help us facilitate implementing fetal RHD genotyping for East Asian populations into clinical practice.

Awareness of paternal age effect disorders among Japanese pregnant women: implications for prenatal genetic counseling for advanced paternal age.

The increasing prevalence of advanced paternal age (APA) has mirrored the rise in maternal age. APA is associated with an increased risk of de novo pathogenic single-nucleotide variants, but this topic has been much less frequently discussed than advanced maternal age (AMA). To explore the awareness of pregnant women regarding paternal age effect (PAE) disorders, a self-administered questionnaire survey was conducted for pregnant women at their first prenatal visit before 17 weeks of gestation. A total of 120 valid respondents (95.2%) were included in the analyses. Of these, 63.3% of pregnant women were aware of PAE disorders. This was markedly lower than the 90.8% recognition of maternal age effect (MAE) disorders. One-third of women with awareness of MAE disorders were not aware of PAE disorders. Pregnant women who were parous, older than their male partners, with knowledge of prenatal testing prior to this pregnancy, and with experience of prenatal testing in a prior pregnancy were significantly more aware of PAE disorders than others. Awareness of PAE disorders was not associated with undergoing prenatal testing during the present pregnancy. Our results show that the prevalence of pregnant women's awareness of PAE disorders was lower than that of MAE disorders. The current study served as a preliminary baseline of information about pregnant women's awareness of PAE disorders. With the introduction of non-invasive prenatal testing, which has the potential to identify PAE disorders, these findings will help the development of a framework for comprehensive prenatal genetic counseling for APA pregnancies.

Pregnant women's opinions toward prenatal pretest genetic counseling in Japan.

In-person models of genetic counseling (GC) have been the common method in Japan for pregnant women to receive GC. However, recent increases in the number of pregnant women considering undergoing prenatal testing have made it challenging to retain individualized in-person care. To explore pregnant women's opinions toward pretest GC models and the ideal time duration, a self-administered questionnaire survey was conducted for women at their first prenatal visit. A total of 114 valid respondents (93.4%) were included in the analyses. Of these, 80.7% of women preferred in-person GC, followed by classroom (9.6%), group (3.5%), and telegenetic-based GC (2.6%). Women with experience in undergoing prenatal testing significantly did not prefer in-person GC (p = 0.05). Sixty-two women (54.4%) preferred a duration of 15-29 min for pretest GC sessions, followed by 30-59 min (28.9%) and <15 min (14.9%). Women's preference of ≥30 min in length was significantly associated with anhedonia, singleton pregnancies, acquaintance with people with trisomy 21, and awareness of prenatal testing. Women who were unaware of the need for agreement with the partner for prenatal testing and who did not know the average life expectancy of a trisomy 21 patient significantly preferred <15 min in length over other durations. While the majority of women preferred in-person GC for <30 min, their preferences varied by their background characteristics, experiences, attitudes, and knowledge. These findings will help establish a prenatal GC system offering a choice of GC models in Japan; however, further large-scale studies are needed to confirm these findings.

Retrospective details of false-positive and false-negative results in non-invasive prenatal testing for fetal trisomies 21, 18 and 13.

OBJECTIVE: Maternal characteristics and neonatal outcomes associated with cell-free DNA (cfDNA) results were analysed retrospectively to assess the details of false-positive and false-negative results after initial blood sampling in non-invasive prenatal testing (NIPT). STUDY DESIGN: A multicentre retrospective study was performed for women undergoing NIPT who received discordant cfDNA results between April 2013 and March 2018. The NIPT data obtained using massive parallel sequencing were studied in terms of maternal background, fetal fraction, z-scores, invasive procedure results and neonatal outcomes after birth. RESULTS: Of the 56,545 women who participated in this study, 54 false-positive (0.095 %) and three false-negative (0.006 %) cases were found. Seven of the 54 false-positive cases (13.0 %) had vanishing twin on ultrasonography. Among the 18 false-positive cases of trisomy 18, confined placental mosaicism (CPM) was confirmed in three cases (16.7 %), while CPM was present in one of the three false-negative cases of trisomy 21. CONCLUSION: These data suggest that the incidence of women with false-positive or false-negative results is relatively low, that such false results can often be explained, and that vanishing twin and CPM are potential causes of NIPT failure. Genetic counselling with regard to false results is important for clients prior to undergoing NIPT.

Emedastine During Pregnancy and Lactation: Emedastine Levels in Maternal Serum, Cord Blood, Breast Milk, and Neonatal Serum.

Background: Emedastine difumarate is a second-generation antihistamine that is more effective for nasal congestion than first-generation antihistamines. The oral form of emedastine is used for the treatment of allergic rhinitis (AR). However, data characterizing emedastine transfer across the placenta and excretion into breast milk are limited. In this case report, we assessed emedastine concentrations in maternal and neonatal blood, cord blood, and breast milk. Materials and Methods: After the patient provided informed consent, emedastine concentrations in maternal serum, breast milk, cord blood, and neonatal serum were measured while the mother was taking oral emedastine 2 mg once daily. Case Report: A 39-year-old woman with AR received emedastine during pregnancy and lactation. Her female infant was born at 37 weeks of gestation with a birth weight of 2,820 g. Emedastine concentrations in maternal serum at 11.5 and 19.0 hours after maternal dosing were 0.39 and 0.22 ng/mL, respectively. The emedastine concentration in cord blood (19.6 hours after maternal dosing) was 0.18 ng/mL. At 24 hours after delivery (44 hours after maternal dosing), emedastine was under the lower limit of quantification (<0.05 ng/mL) in the infant's serum. Emedastine concentrations in breast milk ranged from 0.06 to 0.44 ng/mL. Calculated infant doses through breast milk were much lower than the clinical dose of emedastine. The infant had normal developmental progress and no detectable drug-related adverse effects. Conclusions: Rates of emedastine transfer into placenta and breast milk were low. Further study is required to assess the safety of emedastine in fetuses and breastfed infants.

Pregnant women's preferences for prenatal genetic testing: A single-center study in Japan.

AIM: To evaluate how many pregnant women would prefer to undergo prenatal genetic testing (GT) if they received adequate information during early gestation. METHODS: We examined the preferences for prenatal GT among pregnant women visiting our general outpatient clinic before 16 weeks' gestation between September 2014 and September 2017. We provided them with informational brochures about prenatal GT at their first visit. Women always received genetic counseling (GC) before undergoing GT of their own choice. RESULTS: Among 5700 pregnant women, 2077 (36.4%) received GC, and 1983 (34.8%) underwent some form of prenatal GT. The percentage undergoing GT was 9.4% (50/531) for women <30 years old, 19.0% (309/1623) for those 30-34 years old, 43.1% (989/2294) for those 35-39 years old, and 50.7% (635/1252) for those ≥40 years old. Older pregnant women tended to receive GC and GT more often than younger women (P < 0.001). The most common reason for receiving GC was advanced maternal age (79.7%). The most common prenatal GT was noninvasive prenatal testing (NIPT) (50%), followed by the combined test (29.0%) and quadruple test (11.2%). Pregnant women ≥35 years old tended to choose NIPT (60.5%), while those <35 years old tended to choose the combined test (52.9%). CONCLUSION: About one-third of the pregnant women preferred to receive prenatal GT by their own choice. Women's preferences for prenatal GT increased with maternal age; however, half of pregnant women with an advanced maternal age preferred not to undergo GT, even if they were well informed.

Attitudes toward and current status of disclosure of secondary findings from next-generation sequencing: a nation-wide survey of clinical genetics professionals in Japan.

The management of secondary findings (SFs), which are beyond the intended purpose of the analysis, from clinical comprehensive genomic analysis using next generation sequencing (NGS) presents challenges. Policy statements regarding their clinical management have been announced in Japan and other countries. In Japan, however, the current status of and attitudes of clinical genetics professionals toward reporting them are unclear. We conducted a questionnaire survey of clinical genetics professionals at two time points (2013 and 2019) to determine the enforcement of the SF management policy in cases of comprehensive genetic analysis of intractable diseases and clinical cancer genome profiling testing. According to the survey findings, 40% and 70% of the respondents stated in the 2013 and 2019 surveys, respectively, that they had an SF policy in the field of intractable diseases, indicating that SF policy awareness in Japan has changed significantly in recent years. Furthermore, a total of 80% of respondents stated that their facility had established a policy for clinical cancer genome profiling testing in the 2019 survey. In both surveys, the policies included the selection criteria for genes to be disclosed and the procedure to return SFs, followed by recommendations and proposals regarding SFs in Japan and other countries. To create a better list of the genes to be disclosed, further examination is needed considering the characteristics of each analysis.

Monochorionic diamniotic twins of discordant external genitalia with 45,X/46,XY mosaicism.

BACKGROUND: Monozygotic twins with 45,X/46,XY mosaicism, discordant for phenotypic sex, are extremely rare. METHODS: This report describes the clinical findings of a rare case of 45,X/46,XY mosaicism in monozygotic twins with different external genitalia. Single nucleotide polymorphism (SNP) array analysis, performed by collecting DNA from each umbilical cord, showed identical SNPs in the autosomal chromosomes of both fetuses. RESULTS: Chorionic villus sampling of a 37-year-old primigravida carrying monozygotic twins revealed a 45,X/46,XY karyotype. Autopsy of the aborted fetuses revealed a penis and testes on one fetus and a vagina, uterus, and ovaries in the other fetus--which also had severe cystic hygroma. Cell counting using fluorescence in situ hybridization with XY probes (XY-FISH) showed 20% and 80% abundance of 45,X cells in the internal genitalia, liver, heart, lung, adrenal gland, bone marrow, and spine of the male and female fetuses, respectively. CONCLUSION: These results indicated that the fetuses were genetically monozygotic twins and their different degrees of mosaicism may have resulted in different genital phenotypes.

Nonreportable rates and cell-free DNA profiles in noninvasive prenatal testing among women with heparin treatment.

OBJECTIVE: To evaluate the "nonreportable" rate in patients treated with heparin and to determine the effect of heparin on the results of noninvasive prenatal testing (NIPT). METHOD: This was a single-center retrospective study of NIPT. The "nonreportable" rate of NIPT was evaluated according to presence or absence of heparin treatment. After excluding true-positive cases, a matched cohort study evaluating Z-scores, GC bias, and cell-free DNA (cfDNA) profiles was performed to investigate the effect of heparin on NIPT results. RESULTS: Overall, 2651 singleton pregnancies with available clinical information were evaluated; 23 mothers were treated with heparin. The nonreportable rate was much higher among patients treated with heparin than among those who were not (8.70% vs 0.15%). In the matched cohort study, the Z-scores for chromosomes 13, 18, and 21, and GC bias were significantly higher in the heparin group than in the matched control group. Based on cfDNA library electrophoresis data, the proportion of short-sized cfDNA was higher in the heparin group. CONCLUSION: Heparin use increased the nonreportable rate of NIPT results by borderline Z-scores, possibly caused by the increased proportions of shorter and GC-rich cfDNA fragments. This information will be helpful for prenatal genetic counseling for patients requiring heparin treatment.

Qualitative investigation of the factors that generate ambivalent feelings in women who give birth after receiving negative results from non-invasive prenatal testing.

BACKGROUND: Women who receive negative results from non-invasive prenatal genetic testing (NIPT) may find that they later have mixed or ambivalent feelings, for example, feelings of accepting NIPT and regretting undergoing the test. This study aimed to investigate the factors generating ambivalent feelings among women who gave birth after having received negative results from NIPT. METHODS: A questionnaire was sent to women who received a negative NIPT result, and a contents analysis was conducted focusing on ambivalent expressions for those 1562 women who responded the questionnaire. The qualitative data gathered from the questionnaire were analyzed using the N-Vivo software package. RESULTS: Environmental factors, genetic counseling-related factors, and increased anticipatory anxiety, affected the feeling of ambivalence among pregnant women. Furthermore, pregnant women desired more information regarding the detailed prognosis for individuals with Down syndrome and living with them and/or termination, assuming the possibility that they were positive. CONCLUSIONS: Three major interrelated factors affected the feeling of ambivalence in women. Highlighting and discussing such factors during genetic counseling may resolve some of these ambivalences, thereby enhancing the quality of decisions made by pregnant women.

Distribution of PAPP-A and total hCG between 11 and 13 weeks of gestation in Japanese pregnant women.

Objectives: To establish the reference values for PAPP-A and total hCG between 11 and 13 weeks of gestation for the use of risk assessment of fetal aneuploidy in Japanese pregnant women.Methods: A multicenter prospective study was conducted. The subjects included only Japanese pregnant women with viable singleton who requested the first trimester combined (nuchal translucency and maternal serum marker) screening for fetal aneuploidy. Reference values of PAPP-A and total hCG in Japanese population were made and compared with them in Caucasian.Results: Overall 1,751 Japanese pregnant women were analyzed. Median vales of maternal serum concentration in Japanese pregnant women from 11 + 0-13 + 6 weeks' gestation were ranged from 3.01 to 9.51 mIU/mL for PAPP-A and from 70.2 to 58.3 IU/mL for total-hCG, respectively. Regression curve of median maternal serum PAPP-A and total-hCG concentration against gestational days are significantly higher in Japanese comparing with Caucasian. At most distant values, Japanese serum concentration indicated 1.45 MoM for total-hCG and 1.70 MoM for PAPP-A based on Caucasian regression curves.Conclusion: A modification of the equations by specific reference values is necessary for Japanese pregnant women at the risk assessment of chromosomal abnormalities using the first trimester maternal serum marker.

The Japanese experience and pharmacokinetics of antenatal maternal high-dose immunoglobulin treatment as a prophylaxis for neonatal hemochromatosis in siblings.

Background: Neonatal hemochromatosis (NH) is a rare but serious disease causing fulminant hepatic failure. The recurrence rate of NH in a subsequent infant of a mother with an affected infant is 70-90%. Recently, antenatal maternal high-dose intravenous immunoglobulin (IVIG) treatment has been reported to be effective for preventing NH recurrence. However, data on the IgG concentrations during this treatment are limited.Objective: We report a Japanese experience and present a pharmacokinetic simulation model of IgG during IVIG treatment.Methods: Women with histories of pregnancy diagnosed with NH were treated with IVIG weekly from the second trimester until the end of gestation. Serum IgG levels during treatment were collected frequently and pharmacokinetics were simulated by a two-compartment model.Results: Six women were included during eight pregnancies. None experienced severe adverse events. Three out of eight infants showed temporary liver dysfunction, but none required any treatment. A simulation study showed that the estimated trough and peak levels of IgG concentrations during IVIG were 2000-3000 and 4000-5000 mg/dl, respectively.Conclusion: This treatment prevented the recurrence of NH in siblings in Japanese women. We examined the details of serum IgG concentrations and introduced a new pharmacokinetic simulation model of IgG concentrations during IVIG treatment.

Amplicon Sequencing-Based Noninvasive Fetal Genotyping for RHD-Positive D Antigen-Negative Alleles.

BACKGROUND: To avoid hemolytic disease of the fetus and newborn resulting from maternal alloantibodies against fetal Rh antigens, anti-D immunoglobulin is routinely administered to RhD-negative pregnant women in Japan. Fetal RHD genotyping using cell-free DNA may prevent unnecessary antibody administration; however, current PCR-based methods, which detect RHD deletion, do not address the higher rates of RHD-positive D antigen-negative alleles in nonwhite populations without additional inspections. METHODS: We developed an amplicon-sequencing method that could estimate the type of paternally inherited fetal RHD allele from 4 major RHD alleles in the Japanese population: the D antigen-positive allele (RHD*01, 92.9%) and 3 D antigen-negative alleles (RHD*01N.01, 6.6%; RHD*01EL.01, 0.3%; RHD*01N.04, 0.1%) using cell-free DNA obtained from the blood plasma of pregnant women. RESULTS: The method correctly determined the fetal RhD type even when RhD-negative pregnant women possessed an RHD-positive D antigen-negative allele: RHD*01EL.01 or RHD*01N.04. CONCLUSIONS: This method is a reliable noninvasive fetal RHD genotyping method for Japanese and other East Asian populations. The genotyping principle of amplifying 2 different regions using the same primer pair and distinguishing them by their sequence difference during the subsequent mapping procedure is also theoretically applicable to RHD-positive D antigen-negative alleles prevalent in Africans. Therefore, this method offers an opportunity to consider targeted administration of anti-D immunoglobulin to RhD-negative pregnant women in East Asian and African countries and to increase the specificity of the fetal RHD genotyping implemented nationwide in several European countries.

Effects of Domperidone in Increasing Milk Production in Mothers with Insufficient Lactation for Infants in the Neonatal Intensive Care Unit.

Breast milk is the optimum for all infants, but hospitalization in the neonatal intensive care unit can cause separation of mothers and infants, which often interferes with milk secretion. Some reports show that domperidone is effective in promoting milk secretion. However, the Food and Drug Administration in the United States cautioned to not use domperidone for increasing milk volume because domperidone carries some risk of cardiac events, including QT prolongation, cardiac arrest, and sudden death. In contrast, it is used in Canada, Australia, and the United Kingdom with safety. The pharmacodynamics and pharmacokinetics of drugs may vary by race or ethnic origin, and it is not known whether domperidone is effective or safe for Japanese. In this study we report the effects of domperidone for Japanese mothers with insufficient lactation. Ten mothers were enrolled in a pilot study. After confirming that there were no abnormal findings on the electrocardiogram, the mothers were administered domperidone. Seven of 10 who took domperidone increased their milking volume. Prolactin was increased in 9 of 10 mothers. Adverse events were observed in two mothers, one headache and one abdominal pain; all symptoms were mild and improved promptly; and there were no adverse cardiac events. These results are consistent with reports from other countries. Domperidone may tentatively be considered effective for increasing milk secretion in Japanese mothers as in other populations. Our preliminary study of 10 cases indicates the need for further studies with larger sample sizes to assess the efficacy and safety of domperidone.

Equipoise of recent estimated Down syndrome live births in Japan.

To support people with Down syndrome (DS), it is essential to know and predict the number of live births of children with this condition. In this study, we estimated DS live birth rates on the basis of maternal age distribution and numbers of births in the general population, the maternal-age specific chance for a live birth of a child with DS, and the prenatal diagnosis/termination rate. The total number of live births in Japan decreased to less than 1 million in 2016 and the percentage of women aged 35 years old or over giving birth has increased by sixfold. Prenatal genetic testing in Japan has gradually become more widespread, and 20% of all cases of DS were diagnosed prenatally in 2016. Meanwhile, the annual projected number of DS live births has remained steady at around 2,200 (22 per 10,000 births). In 2016, it was estimated that 70% of all DS babies were born to women of advanced maternal age (AMA). Given that Japan is facing a decreasing birth rate and an aging population, adoption of the practice of prenatal genetic testing for AMA has balanced the number of DS births over the last 7 years from 2010.

Maternal age, history of miscarriage, and embryonic/fetal size are associated with cytogenetic results of spontaneous early miscarriages.

PURPOSE: To clarify the associations of the maternal age, history of miscarriage, and embryonic/fetal size at miscarriage with the frequencies and profiles of cytogenetic abnormalities detected in spontaneous early miscarriages. METHODS: Miscarriages before 12 weeks of gestation, whose karyotypes were evaluated by G-banding between May 1, 2005, and May 31, 2017, were included in this study. The relationships between their karyotypes and clinical findings were assessed using trend or chi-square/Fisher's exact tests and multivariate logistic analyses. RESULTS: Three hundred of 364 miscarriage specimens (82.4%) had abnormal karyotypes. An older maternal age was significantly associated with the frequency of abnormal karyotype (ptrend < 0.001), particularly autosomal non-viable and viable trisomies (ptrend 0.001 and 0.025, respectively). Women with ≥ 2 previous miscarriages had a significantly lower possibility of miscarriages with abnormal karyotype than women with < 2 previous miscarriages (adjusted odds ratio [aOR], 0.48; 95% confidence interval [95% CI], 0.27-0.85). Although viable trisomy was observed more frequently in proportion to the increase in embryonic/fetal size at miscarriage (ptrend < 0.001), non-viable trisomy was observed more frequently in miscarriages with an embryonic/fetal size < 10 mm (aOR, 2.41; 95% CI, 1.27-4.58), but less frequently in miscarriages with an embryonic/fetal size ≥ 20 mm (aOR, 0.01; 95% CI, 0.00-0.07) than in anembryonic miscarriages. CONCLUSIONS: The maternal age, history of miscarriage, and embryonic/fetal size at miscarriage may be independently associated with the frequencies or profiles of cytogenetic abnormalities in early miscarriages.