Published papers

Germline variants in ARID1A have been associated with the so-called BAFopathies, including Coffin-Siris syndrome, which is characterized by hypertrichosis, short fifth finger, thin upper lip, and thick lower lip, is associated with a unique episignature. Hydrocephalus has not been considered part of BAFopathy until recently, when ARID1A variants were implicated in prenatal-onset hydrocephalus. It remains unknown whether ARID1A-associated hydrocephalus is linked to a specific class of variants and whether it exhibits an episignature comparable to that of BAFopathies. We conducted genomic and epigenomic analyses on a fetus diagnosed with severe hydrocephalus on prenatal ultrasound at 19 weeks. After detailed genetic counseling, the pregnancy was terminated at 21 weeks. The delivered fetus exhibited short fifth fingers, thin upper lip, and thick lower lip. Postmortem exome sequencing using umbilical cord blood identified a de novo heterozygous frameshift variant in the last exon of ARID1A (NM_006015.6:c.5259_5262dupGTCT, p.(Ser1755Valfs∗2)). The frameshift variant in the last exon was expected to escape nonsense-mediated mRNA decay (NMD), and we did confirm this through RNA-seq. Concurrent episignature analysis by nanopore sequencing and a support vector machine-based classifier showed that the fetus maps to the BAFopathy group rather than a separate position on the UMAP. Genotype-phenotype correlation analysis of unpublished data from previous reports regarding hydrocephalus and potential NMD escape, with input from the original authors, indicated that the association remains ambiguous. Hence, ARID1A-associated hydrocephalus occurs within the broader clinical and epigenomic spectrum of BAFopathies, but a distinct genetic mechanism caused by NMD escape is unlikely to play a role.

Childhood obesity is a substantial health problem worldwide. The origin of obesity (increased adiposity) can be partly traced back to intrauterine life. However, the determinants of fetal fat deposition remain unclear. This study investigated the association between cord blood adipocytokines related to lipid metabolism (leptin, adiponectin, and insulin-like growth factor-1 [IGF-1]) and fetal adiposity during gestation. A prospective study was conducted in a cohort of 94 singleton pregnancies. Fetal ultrasonography was performed at 24, 30, and 36 weeks of gestation. Estimated fetal adiposity (EFA) was calculated by integrating measurements of cross-sectional arm and thigh fat area percentages and anterior abdominal wall thickness. Plasma cytokine levels and C-peptide immunoreactivity (as a proxy for fetal insulin resistance) were evaluated in cord blood samples obtained at delivery. The associations of cord blood leptin, adiponectin and IGF-1 levels with EFA at 24, 30, and 36 weeks were determined by multiple linear regression, adjusted for potential covariates. The multivariate analyses indicated that leptin was significantly correlated with EFA at 30 and 36 weeks. Leptin was also positively correlated with C-peptide immunoreactivity in the umbilical cord. Cord adiponectin levels were not associated with EFA across gestation. Cord IGF-1 levels were significantly correlated with EFA and estimated fetal body weight (EFW) at 36 weeks. In conclusion, cord leptin was associated with EFA at 30 and 36 weeks, and IGF-1 was associated with EFA at 36 and EFW at 36 weeks. In Conclusion, cord leptin was associated with EFA at 30 and 36 weeks, and IGF-1 was associated with EFA and EFW at 36 weeks. Considering the effects of leptin and IGF-1 on fetal insulin resistance and lipid metabolism, increased levels of leptin and IGF-1 are potential plasma biomarkers of increased fetal adiposity, which may predispose to infant obesity and metabolic dysfunction in later life.

Aim: This study investigated associations between late-night shift work and perinatal outcomes. Methods: Participants were pregnant women with recorded perinatal outcomes (late-night shift group, 626 cases; non-late-night shift group, 6633 cases) identified from two Japanese Internet surveys. We analyzed the association between late-night shift work and adverse perinatal outcomes. Furthermore, we examined factors associated with the use of Maternal Health Management and Guidance Cards. Results: The late-night shift group had significantly higher rates of threatened miscarriage, premature rupture of membranes (PROM), use of the Maternal Health Management and Guidance Card, health problems requiring hospitalization, fetal health problems, and infectious diseases compared with the non-late-night shift group. However, other perinatal outcomes, including preterm birth, gestational age at delivery, mode of delivery, and birth weight, did not differ significantly between groups. Among late-night shift-working mothers, those who used the Maternal Health Management and Guidance Card had a higher incidence of hyperemesis gravidarum, threatened miscarriage, and preterm labor than those who did not. Conclusions: Late-night shift work during pregnancy may be associated with an increased risk of perinatal complications. The Maternal Health Management and Guidance Card may provide support for pregnant women engaged in late-night shift work.

Aim: The induction of labor before due date has recently been proved to reduce the rate of cesarean sections and is not associated with increased risk of adverse perinatal outcomes as compared to expectant management. Controlled-release dinoprostone (PGE2) vaginal insert has recently been approved for use in Japan. However, evidence regarding its efficacy in cervical ripening and labor induction before due date remains limited. We aimed to compare the efficacy of PGE2 vaginal inserts and mechanical dilation for labor induction before due date. Methods: This retrospective cohort study included 206 mothers at 37, 38, and 39 weeks' gestation delivered at our institution between January 2021 and October 2022. Perinatal outcomes, including the success rate of vaginal delivery, were compared between the PGE2 (n = 46) and metreurynter/laminaria tent (non-PGE2) (n = 160) groups. The success rate of vaginal delivery was defined as the proportion of women who delivered vaginally within 48 h of initiating oxytocin augmentation. Results: The success rate of vaginal delivery was significantly higher in the PGE2 group (37/49, 80.4%) than in the non-PGE2 group (106/177, 66.2%). Emergency cesarean section related to non-reassuring fetal status was performed with none in the PGE2 group and with eight (5.0%) in the non-PGE2 group. Conclusions: The rate of vaginal delivery was significantly higher in the PGE2 group for elective labor induction between 37 and 39 weeks. The PGE2 vaginal insert could increase the success rate of vaginal delivery for elective induction of labor at 39 weeks.

25-hydroxyvitamin D (25(OH)D) regulates lipid metabolism, and its decrease is proposed as a pathogenesis of metabolic syndrome, gestational diabetes mellitus (GDM), and eventually fetal adiposity. Decreased 25(OH)D is also linked with the development of gestational diabetes mellitus (GDM), which is associated with increased fetal adiposity. Fetuses are dependent on the supply of 25(OH)D from maternal circulation. However, the influence of maternal serum 25(OH)D on fetal adiposity remains unclear. This study aimed to investigate the association between maternal serum 25(OH)D and fetal adiposity. A prospective longitudinal study was conducted in a cohort of 89 (including 21 GDM) singleton pregnancies. Maternal blood samples were obtained at 10, 24, 30, and 36 weeks, and fetal ultrasonography was performed at 24, 30, and 36 weeks of gestation. Estimated fetal adiposity (EFA) was calculated as the average z-score of cross-sectional arm and thigh percentage fat area and anterior abdominal wall thickness as previously reported. The multiple linear regression analyses indicated that maternal 25(OH)D levels across gestation were not associated with EFA at 24 and 30 weeks, while maternal 25(OH)D at 24 weeks was inversely correlated with EFA at 36 weeks. Particularly, in the GDM group, maternal 25(OH)D levels at 10, 24, 30, and 36 weeks all showed a significant negative correlation with EFA at 36 weeks. Decreased maternal serum 25(OH)D level could be an early biomarker of increased fetal adiposity in late gestation, especially in diabetic pregnancies.

Mirror syndrome is a rare obstetric condition characterized by maternal fluid retention mirroring fetal hydrops. Placental ectopic liver tissue is an extremely rare non-trophoblastic placental tumor, potentially arising from aberrant hepatoblast migration. While its association with fetal hydrops has been reported, the clinical significance remains uncertain. We present a patient of maternal mirror syndrome linked to fetal hydrops due to a de novo SOS1 variant, with histopathological identification of placental ectopic liver tissue. A 32-year-old woman was admitted at 31 weeks’ gestation with fetal hydrops, presenting with bilateral pleural effusions, ascites, and subcutaneous edema. Due to worsening maternal pleural effusion, she was transferred to our hospital at 31 weeks and 6 days. Given progressive maternal and fetal deterioration, an emergency cesarean section was performed at 32 weeks due to concerns regarding maternal mirror syndrome. The female infant was delivered with severe respiratory distress and succumbed at 9 days of age. Trio-based exome sequencing identified a de novo heterozygous SOS1 variant (NM_005633.4:c.512T > A [p.V171G]), confirming a postmortem diagnosis of Noonan syndrome. Histopathological analysis of the placenta revealed ectopic liver tissue within the villi, confirmed by positive immunostaining for hepatocyte markers. A recent report of RIT1-associated mirror syndrome and non-immune hydrops fetalis (NIHF) further supports the role of Rasopathies in the pathogenesis of mirror syndrome. Our findings confirm that mirror syndrome is a potential manifestation of Rasopathies, while the role of ectopic liver tissue in the placenta remains uncertain. Future research should focus on genetic factors underlying mirror syndrome rather than incidental placental anomalies.

Aims/Introduction: This study evaluated the risk factors for insulin therapy before 24 gestational weeks (early insulin therapy) in pregnant women with gestational diabetes diagnosed before 24 gestational weeks (E-GDM). Materials and Methods: This study included 530 singleton mothers with E-GDM who underwent a 75 g oral glucose tolerance test (OGTT) in the first trimester at Keio University Hospital between January 2013 and December 2021. E-GDM can be classified according to its management into only diet therapy until delivery (Diet E-GDM), insulin therapy started before 24 gestational weeks (EarlyIns E-GDM), and insulin therapy started after 24 gestational weeks (LateIns E-GDM). We analyzed the risk factors for EarlyIns E-GDM. Results: Patients with EarlyIns E-GDM had a significantly higher maternal age at delivery, pre-pregnancy BMI, first trimester hemoglobin A1c, 1 h plasma glucose levels (1 h-PG), and 2 h-PG, as well as a more pronounced initial increase and subsequent decrease, compared with those in the Diet E-GDM group. However, the Apgar scores at both 1 and 5 min were significantly lower in patients with EarlyIns E-GDM than in those with Diet E-GDM. The number of abnormal values in the OGTT showed the largest area under the receiver operating characteristic curve (AUC) for predicting EarlyIns E-GDM (0.83, 95% confidence interval [CI]: 0.79–0.86), followed by the 1 h-PG value (AUC: 0.81, 95% CI: 0.77–0.85). The initial increase showed the third largest AUC (0.78, 95% CI: 0.74–0.82). Conclusions: Although further research is needed, our data suggest the importance of early insulin therapy in cases of E-GDM with multiple abnormal OGTT values, especially with high 1 h-PG levels and initial increase.

Background and Objectives: Preterm birth (PTB) imposes a substantial medical and economic burden on perinatal care. Recent advances in 16S rRNA gene sequencing help detailed microbiota analysis. Understanding microbiota’s contribution may help in understanding PTB pathogenesis. We aim to investigate the microbiota profiles of the oral, vaginal, and placental microbiota in pregnant Japanese women hospitalized for care of preterm labor and examine the association between them and perinatal outcomes. Materials and Methods: This cross-sectional study included 20 pregnant Japanese women admitted to a single perinatal center for preterm labor between 2022 and 2023. Oral, vaginal, and placental samples were collected aseptically during hospitalization. The patients were retrospectively categorized into: term birth (TB, n = 10), chronic abruption-oligohydramnios sequence (CAOS, n = 3), and PTB without CAOS (PTB, n = 7) perinatal outcomes. Microbiota profiles were analyzed using 16S rRNA gene sequencing, and group comparisons were performed using univariate statistical methods. Results: Alpha or beta diversity of the oral and vaginal microbiota among the three groups did not differ significantly. CAOS and PTB groups showed a trend toward altered vaginal microbial composition, but not the TB group. In the placental microbiota, beta diversity differed significantly among the TB, PTB, and CAOS groups. Ureaplasma urealyticum was more abundant in the PTB group, whereas Ureaplasma parvum was more abundant in the CAOS group. Conclusions: A potential shift in the vaginal microbiota and alterations in the placental microbiota, observed in PTB, including CAOS, suggested a possible microbial contribution.

Birth weight is an important predictor of perinatal complications and long-term health outcomes of offspring. Fetal programming influenced by maternal obesity, overnutrition, and hyperglycemia has been proposed as the fuel overload hypothesis. Recent investigations related with fetal body composition have revealed that neonatal adiposity can be predicted by fetal fat mass, and that maternal insulin resistance and serum leptin level are indicators of fetal adiposity. Based on the current evidence, the origins of obesity can partly be traced back into the fetal life. Further clarification of the determinants of fetal fat mass may lead to the clinical interventions and treatment strategies for fetal growth and development. This effort potentially leads to the elucidation of pathological conditions related with long-term health outcomes and the primary prevention of childhood obesity and early onset metabolic syndrome.

Objective: This study aimed to describe the perinatal and neonatal outcomes of chronic abruption oligohydramnios sequence in the Kanto region of Japan. Methods: This survey was conducted at 123 perinatal centers affiliated to this area. Data on the experience of managing chronic abruption oligohydramnios sequence between 1 January 2017, and 31 December 2022, were collected and analyzed. Results: Among the 82 cases of chronic abruption oligohydramnios sequence that were included in this study, there were seven miscarriages, five artificial abortions, and 70 deliveries beyond 22 gestational weeks (singleton: 68; twin: 2). In 82 patients, vaginal bleeding was the initial symptom of chronic abruption oligohydramnios sequence (88%). The mean gestational duration at the initial symptom onset was 17.3 ± 5.0 weeks. Of the 68 singleton pregnancies delivered after 22 gestational weeks, the mean gestational duration at delivery was 25.2 ± 2.8 weeks. In patients with chronic abruption oligohydramnios sequence, the mean white blood cell count at diagnosis and mean of the maximum white blood cell count during pregnancy were 11,589 ± 2885 and 15,357 ± 4745/μL, respectively; and the mean C-reactive protein at diagnosis and mean of the maximum C-reactive protein during pregnancy were 1.0 ± 1.2 and 2.0 ± 2.1 mg/L, respectively. Chorioamnionitis was identified in 43 patients (63%). All neonates were admitted to the neonatal intensive care unit. Of the 68 singleton neonates, 5 died immediately after birth. Conclusions: Chronic abruption oligohydramnios sequence is a rare perinatal complication that is possibly associated with infections, such as chorioamnionitis, and linked to adverse perinatal and neonatal outcomes.

Background/Objectives: Recently, it was reported that glucose variability (GV) calculated using the 75 g oral glucose tolerance test (OGTT) is associated with adverse perinatal outcomes. However, its role in gestational diabetes mellitus (GDM) remains unclear. We investigated the association between GV and insulin parameters in Japanese women diagnosed with GDM after 24 weeks of gestation (late GDM). Methods: A total of 280 mothers with late GDM cared for at Keio University Hospital were included in this study. Using 75 g OGTT, the initial increase and subsequent decrease were calculated as the GV. Results: The initial increase was significantly positively associated with 1 h plasma glucose level (PG) and 2 h PG with 75 g OGTT (p < 0.001), but fasting PG, insulinogenic index (IGI), and homeostasis model assessment—insulin resistance were negatively associated with the initial increase (all p < 0.001). The subsequent decrease was significantly positively correlated with 1 h PG (p < 0.001) but negatively correlated with 2 h PG (p < 0.001), IGI (p = 0.009), and the whole-body insulin sensitivity index derived from the OGTT (p = 0.02). Insulin Secretion-Sensitivity Index-2 was not associated with an initial increase or subsequent decrease. Conclusions: Since the initial increase might reflect insulin secretion and the subsequent decrease might reflect insulin sensitivity in Japanese women with late GDM, GV could alter several insulin parameters. Further studies are required to investigate the usefulness of GV in the management of GDM.

Introduction: Insulin-like growth factor-1 (IGF-1) promotes protein and carbohydrate metabolism, which consequently affects birth weight. Fetal fractional limb volume has been proposed as a useful parameter for predicting birth weight and quantifying fetal soft tissue development. However, the relationship between umbilical cord serum IGF-1 levels and fetal fractional limb volume remains unclear. Herein, we aimed to investigate the association of cord serum IGF-1 levels with longitudinal changes in fetal fractional limb volume in uncomplicated pregnancies. Material and Methods: In this prospective study, 96 singleton pregnancies were followed. Fetal 3D ultrasonography was performed longitudinally at 24, 30, and 36 weeks of gestation to assess fractional arm volume and thigh volumes as cylindrical limb volumes, derived from 50% of the fetal total diaphysis length. Cord serum IGF-1 levels were measured using an electrochemiluminescence immunoassay. The relationship between cord blood IGF-1 levels and fetal fractional limb volume was analyzed using multiple linear regression; adjusted for potential confounding factors including maternal age, parity, pre-pregnancy body mass index, gestational weight gain, fetal sex, and gestational age at assessments. Results: Mean cord serum IGF-1 was 52.8 ± 18.4 ng/mL (mean ± SD). IGF-1 levels were not associated with fetal fractional limb volumes at 24 weeks and 30 weeks but were significantly correlated with fractional arm volume (r = 0.290, p = 0.006) and fractional thigh volume (r = 0.289, p = 0.006) at 36 weeks. After adjusting for covariates, cord serum IGF-1 explained 7.0% and 10.6% of the variation in fractional arm and thigh volumes at 36 weeks, respectively. Although IGF-1 was significantly correlated with the birth weight percentile, it did not correlate with the estimated fetal weight at 36 weeks. Conclusions: Cord serum IGF-1 levels significantly correlated with fetal fractional limb volumes in late gestation. Fractional limb volume may be an earlier and more sensitive ultrasound parameter affected by serum IGF-1 level than estimated fetal weight.

We aimed to provide a comparative analysis of the vaginal microbiota in pregnant women who underwent cervical conization (CZ) and radical trachelectomy (RT) for cervical intraepithelial neoplasia or early-stage cervical cancer. We included 114 pregnant Japanese women who underwent CZ group (n = 13), RT group (n = 20), or received no cervical treatments (CON group: n = 81) and cared at Keio University Hospital between 2019 and 2023. The differences in vaginal microbiota during the first, second, and third trimester using V1–V2 region of the 16S ribosomal RNA were investigated. Higher species diversity was observed in the CZ and RT groups than in the CON group; however, the abundance and composition of Lactobacillus were similar. The rate of preterm delivery in women who underwent cervical treatments was significantly higher than that in those who had full-term delivery; however, the species diversity and abundance or composition of Lactobacillus was not associated with preterm birth. Women who underwent CZ or RT had higher microbial species diversity than women who did not undergo a procedure; however, Lactobacillus abundance and composition remained the same. The cause of preterm delivery in women who received cervical treatment was not associated with Lactobacillus species diversity or abundance.

Even in the context of modern medicine, infants with fetal and neonatal neurological diseases such as cerebral palsy and myelomeningocele suffer serious long-lasting impairment due to the irreversible neuronal damage. The promotion of neurologically intact survival in patients with perinatal intractable neurological diseases requires the development of novel strategies. One promising strategy involves the use of human amniotic fluid stem cells (hAFSCs), which have attracted much attention in recent years and are known to exert anti-inflammatory and neuroprotective effects. In recent years, the therapeutic effects of hAFSCs on fetal-neonatal neurological diseases have become evident as per intense research efforts by our group and others. Specifically, hAFSCs administered into the nasal cavity migrated to the brain and controlled local inflammation in a rodent model of neonatal hypoxic-ischemic encephalopathy. In contrast, hAFSCs administered intraperitoneally did not migrate to the brain; they rather formed spheroids in the abdominal cavity, resulting in the suppression of systemic inflammation (including in the brain) via the secretion of anti-inflammatory cytokines in concert with peritoneal macrophages in a rodent model of periventricular leukomalacia. Moreover, studies in a rat model of myelomeningocele suggested that hAFSCs administered in utero secreted hepatocyte growth factor and protected the exposed spinal cord during pregnancy. Importantly, autologous hAFSCs, whose use for fetal-neonatal treatment does not raise ethical issues, can be collected during pregnancy and prepared in sufficient numbers for therapeutic use. This article outlines the results of preclinical research on fetal stem cell therapy, mainly involving hAFSCs, in the context of perinatal neurological diseases.

Background: Maternal obesity influences birth weight and newborn adiposity. Fetal fractional limb volume has recently been introduced as a useful parameter for the proxy of fetal adiposity. However, the association between maternal adiposity and the growth of fetal fractional limb volume has not been examined. Aims: To investigate the association of maternal pre-pregnancy BMI with the growth of fetal fractional limb volume. Study design: Prospective cohort study. Subjects: Women with singleton uncomplicated pregnancies enrolled between July 2017 and June 2020. Outcome measures: Fetal fractional limb volume was assessed between 20 and 40 weeks' gestation, measured as cylindrical limb volume based on 50 % of the total diaphysis length. The measured fractional limb volume at each gestational week were converted to z-scores based on a previous report. The association between pre-pregnancy BMI and fetal fractional limb volume was examined. Maternal age, parity, gestational weight gain and fetal sex were considered as potential confounding variables. Results: Ultrasound scans of 455 fractional arm volume and thigh volume were obtained. Fractional limb volume increased linearly until the second trimester of gestation, then increased exponentially in the third trimester. Maternal pre-pregnancy BMI was significantly correlated with z-scores of fractional arm volume and thigh volume across gestation. The post-hoc analysis showed the association between pre-pregnancy BMI and fractional arm volume was significant especially between 34 and 40 weeks. Conclusions: Maternal obesity influences the growth pattern of fetal fractional limb volume. Fractional arm volume may potentially provide a useful surrogate marker of fetal nutritional status in late gestation.

To evaluate perinatal outcomes and risk factors for large for gestational age (LGA; birth weight over 90 percentile) in gestational diabetes diagnosed before 24 gestational weeks and treated with diet therapy alone until delivery (Diet Early gestational diabetes mellitus (Diet Early GDM)), we assessed the maternal characteristics and perinatal outcomes of patients with early GDM (n = 309) and normal glucose tolerance (NGT; n = 309) at Keio University Hospital. The gestational weight gain (GWG) expected at 40 weeks was significantly lower in the Diet Early GDM group than in the NGT group. The Diet Early GDM group exhibited a significantly lower incidence of low birth weight (<2500 g) and higher Apgar score at 5 min than the NGT group. Multiple logistic regression analysis revealed that the pre-pregnancy body mass index and GWG expected at 40 weeks were significantly associated with LGA for Diet Early GDM. No differences were observed in random plasma glucose levels in the first trimester, 75 g oral glucose tolerance test values, and initial increase or subsequent decrease between the two groups. Dietary early GDM did not exhibit a worse prognosis than NGT. To prevent LGA, it might be important to control maternal body weight not only during pregnancy but also before conception.

Ascending inflammation from the vagina is a major cause of preterm birth. Currently, this condition—especially when uncontrolled—has no effective treatment. Human amniotic fluid stem cells (hAFSCs) are mesenchymal stem cells known to exert potent anti-inflammatory effects in animal models of perinatal diseases, such as periventricular leukomalacia, myelomeningocele, and neonatal sepsis. However, hAFSC therapy for inflammation-induced preterm birth has not been tested. In order to determine the therapeutic effect of hAFSC transplantation, we employed a preterm mouse model of ascending infection; this model was constructed by administering lipopolysaccharide to pregnant mice. We investigated the preterm birth rate and evaluated the inflammation of tissues, which is related to progressive infections, such as those involving the cervix, placenta, and lavage cells, using real-time qPCR. Further, we tracked the fluorescence of fluorescently labeled hAFSCs using an in vivo imaging system, and hAFSC aggregation was evaluated using immunohistochemistry analysis. We also investigated the presence of multiple types of peritoneal macrophages via flow cytometry analysis. Finally, we performed sphere culturing and co-culturing to determine the therapeutic effects of hAFSCs, such as their anti-inflammatory effects and their potential to alter macrophage polarization. We found that hAFSC administration to the peritoneal cavity significantly reduced inflammation-induced preterm birth in the mouse model. The treatment also significantly suppressed inflammation of the placenta and cervix. Transplanted hAFSCs may have aggregated with peritoneal macrophages, switching them from an inflammatory to an anti-inflammatory type. This property has been reported in vivo previously, but here, we examined the effect in vitro. Our findings support the hypothesis that hAFSCs suppress inflammation and reduce preterm birth by switching macrophage polarity. This study is the first to demonstrate that hAFSCs are effective in the treatment and prevention of inflammation-induced preterm birth.