Published papers

Background: We investigated the use of virtual telehealth visits (VV) for prenatal checkups in Japan during the coronavirus disease (COVID-19) pandemic, identified challenges associated with their use, and assessed the feasibility of future VV implementation for prenatal care. Methods: Surveys were conducted at birthing facilities across Japan and with pregnant women attending Osaka and Keio University hospitals. To assess the feasibility of VV, we compared the self-measured blood pressure, fundal height, urinary test results, and fetal heart rate of pregnant women with those measured by healthcare providers. Results: We received responses from 1,096 birthing facilities (49.5% response rate) and 96 women. Only 1.6% of birthing facilities implemented VV, mainly due toto a lack of human resources, costs, and low demand from both patients and healthcare providers. In contrast, 60.2% of pregnant women expressed anxiety about in-person visits during the pandemic, and 36.6% preferred the introduction of VV. The Pearson correlation coefficients between self-measured and provider-measured values systolic and diastolic blood pressure and fundal height were 0.68, 0.58, and 0.87, respectively. The concordance rates for proteinuria and urinary glucose were 91.6% and 98.9%, respectively. However, the correlation for fetal heart rate measurements was poor (-0.04). Bland–Altman analysis revealed 95% limits of agreement ranging from -42.6 to 65.6 bpm, indicating the need for methodological improvement. Conclusion: Despite maternal interest, VV has been limitedly implemented in Japan. Our study found that self-measured values, except for fetal heart rate, were highly correlated with those measured by healthcare providers. These findings are important for healthcare providers and government agencies when considering future prenatal checkups.

The aim of this study is to investigate glucose metabolism longitudinally during pregnancy to explore mechanisms underlying gestational diabetes mellitus (GDM). We reviewed a total of 62 pregnant Japanese women who underwent a 75g oral glucose tolerance test (OGTT) twice during pregnancy (median: early, 13; late, 28 weeks' gestation) because of positive GDM screening. All showed normal OGTT results in early pregnancy. Based on late OGTT, 15 had GDM (late- onset GDM) and 47 normal glucose tolerance (NGT). In early pregnancy, there were no significant differences in insulin sensitivity (insulin sensitivity index derived from OGTT [ISOGTT] and homeostasis model assessment for insulin resistance [HOMA-IR]) and insulin secretion (a ratio of the total area-under-the-insulin-curve to the total area-under-the-glucose-curve [AUCins/glu] and insulinogenic index [IGI]) between the NGT and late-onset GDM groups. In each group, insulin sensitivity significantly decreased from early to late pregnancy, most in the late-onset GDM group (each p < 0.05). The insulin secretion showed no significant changes with advancing pregnancy in both of the groups, although late-onset GDM showed significantly lower IGI compared with NGT in late OGTT (p < 0.05). When assessed beta cell function by OGTT-derived disposition index (i.e. Insulin Secretion-Sensitivity Index-2 and IGI/fasting insulin), the indices significantly decreased from early to late pregnancy in the both groups (each p < 0.05). Women with late-onset GDM showed significantly lower indices compared with NGT (each p < 0.05). The failure of beta cell to compensate for decreased insulin sensitivity could contribute to the development of the late-onset GDM.

INTRODUCTION: The average birth weight in Japan has gradually decreased and the number of low birth weight infant has increased over the last 30 years. Japanese pregnant women are characterized with lower prevalence of obesity than those in other developed countries, and maternal underweight before pregnancy is independently associated with low birth weight. However, the association between maternal inadequate gestational weight gain (GWG) and the risk of small for gestational age (SGA) in Japanese uncomplicated pregnant women has not been fully understood. This study aimed to examine the effect of maternal inadequate GWG on the risk of SGA in Japanese uncomplicated pregnancies. METHODS: We retrospectively analyzed uncomplicated Japanese singleton pregnancies that delivered at term gestation in our institution from 2006 to 2016. The association between GWG and birth weight was analyzed by multiple linear regression. Potential confounding factors included maternal age, parity, prepregnancy BMI, and neonatal sex. The association between inadequate GWG and SGA was also examined by logistic regression. RESULTS: A total of 3837 mother-neonate dyads were analyzed. Maternal GWG was 10.1 +/- 3.7 kg (mean +/- SD), and 2529 (66%) had inadequate GWG. After adjusting for confounding factors, GWG significantly correlated with birth weight (standardized beta = 0.199, p < .001). Inadequate GWG increased the risk of delivering SGA neonate (adjusted odds ratio (aOR) = 1.97 [1.45-2.68], p < .001). This association was particularly pronounced in underweight (aOR = 2.95 [1.38-6.29], p = .005) and normal weight mothers (aOR = 1.79 [1.27-2.52], p = .001), and not in overweight/obese mothers (p = .115). CONCLUSION: Maternal GWG is associated with birth weight in Japanese women with uncomplicated singleton pregnancies. Inadequate GWG is an important risk factor of SGA, particularly in non-obese women. The present finding would potentially provide further evidence that promoting adequate gestational weight gain in Japanese underweight and normal weight mothers would reduce SGA, as well as metabolic dysfunction in later life.

OBJECTIVE: To investigate the association between mid-trimester residual cervical length (CL) and the risk of preterm birth in pregnancies after abdominal radical trachelectomy (RT). DESIGN: Retrospective cohort study. SETTING: University hospital. POPULATION: A total of 33 deliveries after 22 weeks' gestation in 30 women who underwent abdominal RT including prophylactic cervical cerclage and perinatal care between January 2002 and May 2016. METHODS: The association between mid-trimester residual CL (the distance between the cerclage and the external cervical os) and gestational age at delivery was investigated. Receiver-operating characteristics (ROC) curve analysis was performed to estimate the optimal cut-off values of the mid-trimester residual CL for the prediction of preterm birth. MAIN OUTCOME MEASURES: Preterm birth before 34 weeks' gestation. RESULTS: Mid-trimester residual CL showed a significant correlation with gestational age at delivery (r = 0.36, P < 0.05). There was a significant difference in residual CL between women who did and those who did not give birth before 34 weeks (P < 0.05). Mid-trimester residual CL < 13 mm was a good predictor of birth before 34 weeks, with a sensitivity of 67%, specificity of 75%, positive predictive value of 55% and negative predictive value of 86% (area under ROC curve, 0.75). CONCLUSIONS: Mid-trimester residual CL is significantly correlated with gestational age at delivery. Residual CL assessment could be used to reassure physicians and women that there is only a small chance of preterm birth in pregnancies after abdominal RT. TWEETABLE ABSTRACT: Mid-trimester residual cervical length is a good predictor of preterm birth after radical trachelectomy.

Despite the poor prognosis associated with myelomeningocele (MMC), the options for prenatal treatments are still limited. Recently, fetal cellular therapy has become a new option for treating birth defects, although the therapeutic effects and mechanisms associated with such treatments remain unclear. The use of human amniotic fluid stem cells (hAFSCs) is ideal with respect to immunoreactivity and cell propagation. The prenatal diagnosis of MMC during early stages of pregnancy could allow for the ex vivo proliferation and modulation of autologous hAFSCs for use in utero stem cell therapy. Therefore, we investigated the therapeutic effects and mechanisms of hAFSCs-based treatment for fetal MMC. hAFSCs were isolated as CD117-positive cells from the amniotic fluid of 15- to 17-week pregnant women who underwent amniocentesis for prenatal diagnosis and consented to this study. Rat dams were exposed to retinoic acid to induce fetal MMC and were subsequently injected with hAFSCs in each amniotic cavity. We measured the exposed area of the spinal cord and hepatocyte growth factor (HGF) levels at the lesion. The exposed spinal area of the hAFSC-treated group was significantly smaller than that of the control group. Immunohistochemical analysis demonstrated a reduction in neuronal damage such as neurodegeneration and astrogliosis in the hAFSC-treated group. Additionally, in lesions of the hAFSC-treated group, HGF expression was upregulated and HGF-positive hAFSCs were identified, suggesting that these cells migrated to the lesion and secreted HGF to suppress neuronal damage and induce neurogenesis. Therefore, in utero hAFSC therapy could become a novel strategy for fetal MMC. Stem Cells Translational Medicine 2019.

According to the 2004 Japanese definition, early-onset (EO) preeclampsia (PE) is defined as PE occurring at <32 weeks of gestation. This was based on the presence of “dual peaks” (30–31 and 34–35 weeks) in the prevalence of severe forms of hypertension. In contrast, the international definition adopted a cutoff of 34 weeks based on the consensus. Our aim was to investigate whether there were “dual peaks” in the gestational-age-specific incidence or prevalence of PE onset in pregnant women who underwent maternal check-ups at <20 weeks of gestation in a multicenter retrospective cohort study. Diagnoses of PE and superimposed preeclampsia (SPE) were based on the new Japanese definition. A total of 26,567 pregnant women with singleton pregnancy were investigated. The best fitting equations for the distribution of the onset of gestational-age-specific incidence (hazard) rates of PE/SPE, PE, and PE with severe hypertension (a systolic blood pressure ≥160 and/or a diastolic blood pressure ≥110 mmHg) were investigated using the curve estimation function in SPSS. PE/SPE occurred in 1.83% of the patients. EO-PE/SPE with onset at <32 and <34 weeks of gestation and preterm PE/SPE occurred in 0.38, 0.56, and 1.07% of the patients, respectively. Gestational-age-specific incidence rates of PE/SPE, PE, and PE with severe hypertension showed exponential increases, with very high R2 values (0.975, 0.976, and 0.964, respectively). There were no “dual peaks” in the prevalence rates of women with SPE/PE, PE, and PE with severe hypertension. In conclusion, the absence of “dual peaks” refutes the previous rationale of EO-PE being defined as PE at <32 weeks of gestation. Further studies to determine an appropriate definition of EO-PE/SPE are needed.

Background: Newborns exhibit substantial variation in fat mass accretion over gestation. These individual differences in newborn adiposity extend into infancy and childhood and relate to subsequent risk of obesity and metabolic dysregulation. Maternal glucose homeostasis in pregnancy has been proposed as an underlying mechanism; however, the timing in gestation when maternal glucose regulation influences the progression of fetal fat deposition remain unclear. Objective: This study aimed to investigate the cross-sectional and longitudinal association of maternal insulin resistance in early, mid, and late pregnancy with fetal fat deposition in uncomplicated pregnancies. We hypothesized that maternal insulin resistance at early, mid, and late gestation is positively associated with fetal fat deposition, and that the magnitude of the association is greater for the mid and late gestation measures than for the early gestation measure. Study Design: In a longitudinal study of 137 low-risk pregnancies, a fasting maternal blood sample was obtained and fetal ultrasonography was performed at ≈ 12, 20, and 30 weeks’ gestation. Maternal insulin resistance was quantified using the homeostasis model assessment of insulin resistance (fasting insulin×fasting glucose/405). Estimated fetal adiposity was calculated by integrating measurements of cross-sectional arm and thigh percentage fat area and anterior abdominal wall thickness. The associations between maternal homeostasis model assessment of insulin resistance and estimated fetal adiposity and estimated fetal weight were determined by multiple linear regression adjusted for potential confounding factors including maternal age, parity, race and ethnicity, prepregnancy body mass index, gestational weight gain per week, fetal sex, and gestational age at assessments. Results: Maternal homeostasis model assessment of insulin resistance at ≈ 12, 20, and 30 weeks was 2.79±1.79 (±standard deviation), 2.78±1.54, and 3.76±2.30, respectively. Homeostasis model assessment of insulin resistance at 20 weeks was positively associated with estimated fetal adiposity at 20 weeks (r=0.261; P=.005). Homeostasis model assessment of insulin resistance at 20 weeks (r=0.215; P=.011) and 30 weeks (r=0.285; P=.001) were also positively associated with estimated fetal adiposity at 30 weeks. These relationships remained significant after adjustment for confounding factors. There was no significant correlation between homeostasis model assessment of insulin resistance and estimated fetal weight at 20 and 30 weeks’ gestation. Conclusion: In low-risk pregnancies, maternal insulin resistance at mid and late but not early pregnancy is significantly associated with fetal adiposity but not with fetal weight. Maternal insulin resistance in mid-gestation could provide a basis for risk identification and interventions that target child adiposity.

Based on epidemiological and experimental evidence, the origins of childhood obesity and early onset metabolic syndrome can be extended back to developmental processes during intrauterine life. It is necessary to actively investigate antecedent conditions that affect fetal growth by developing reliable measures to identify variations in fetal fat deposition and body composition. Recently, the resolution of ultrasonography has remarkably improved, which enables better tissue characterization and quantification of fetal fat accumulation. In addition, fetal fractional limb volume has been introduced as a novel measure to quantify fetal soft tissue volume, including fat mass and lean mass. Detecting extreme variations in fetal fat deposition may provide further insights into the origins of altered fetal body composition in pathophysiological conditions (i.e., fetal growth restriction or fetal macrosomia), which are predisposed to the metabolic syndrome in later life. Further studies are warranted to determine the maternal or placental factors that affect fetal fat deposition and body composition. Elucidating these factors may help develop clinical interventions for altered fetal growth and body composition, which could potentially lead to primary prevention of the future risk of metabolic dysfunction.

BACKGROUND: To investigate perinatal outcomes in pregnancy after high-dose medroxyprogesterone acetate (MPA) therapy for early stage endometrial cancer (EC) and atypical endometrial hyperplasia (AEH) and to determine whether pregnancy after MPA therapy is at a higher risk of placenta accreta. METHODS: Data of 51 pregnancies in 46 women who received MPA therapy for EC or AEH and delivered after 22 weeks of gestation at Keio University Hospital were reviewed. A retrospective matched case-control study was performed to determine the risk of placenta accreta in pregnancy after MPA therapy compared with singleton pregnancies without any history of maternal malignancy treatments. RESULTS: The incidence of placenta accreta was higher in the MPA group than in the control group (15.7 vs. 0%, p = 0.0058). However, no differences in other perinatal outcomes were observed between groups. While gestational weeks at delivery in the MPA group were later than those in the control group (p = 0.0058), no difference in the incidence of preterm delivery was recorded between groups. In the MPA therapy group, the number of patients who underwent ≥ 6 dilation and curettage (D&C) was higher in the placenta accreta group than in the non-placenta accreta group (50.0 vs. 14.0%, p = 0.018). Patients with ≥ 6 D&Cs demonstrated a 6.0-fold increased risk of placenta accreta (p = 0.043, 95% CI 1.05-34.1) than those receiving ≤ 3 D&Cs. CONCLUSION: Pregnancy after MPA therapy is associated with a high risk of placenta accreta. In cases in which the frequency of D&C is high, placenta accreta should be considered.

Late preterm (LP, born between 34 0/7 and 36 6/7 weeks of gestation) infants may experience several adverse outcomes, similar to those experienced by low birthweight (LBW, birthweight <2500 g) infants. However, while LP infants are often born with LBW, the association between LP and LBW remains unknown. This study aimed to investigate LBW rate and independent risk factors for LBW in LP singleton neonates. We retrospectively analyzed data of LP singleton neonates, born between 2013 and 2017, from the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System. The exclusion criteria included stillbirths and infants with missing data. Logistic regression analyses were performed to investigate maternal and perinatal factors associated with LBW in LP singletons. LBW was observed in 62.5% (n = 35,113) of 56,160 LP singleton births. In the multiple logistic regression analysis, LBW in LP neonates was independently associated with modifiable maternal factors, including pre-pregnancy underweight, inadequate gestational weight gain, and smoking during pregnancy, as well as non-modifiable factors, including younger maternal age, nulliparity, hypertensive disorder of pregnancy, preeclampsia, cesarean section delivery, and female offspring. According to the Japanese pregnancy birth registry data, more than half of LP neonates were LBW. We previously discussed the issue of LBW regarding infants with different backgrounds, as there are many different causes of LBW. Several risk factors should be subdivided and considered for the risk of LP and LBW.

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.

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.

High titer of maternal thyroid-stimulating hormone receptor antibody (TRAb) in patients with Graves' disease could cause fetal hyperthyroidism during pregnancy. Clinical features of fetal hyperthyroidism include tachycardia, goiter, growth restriction, advanced bone maturation, cardiomegaly, and fetal death. The recognition and treatment of fetal hyperthyroidism are believed to be important to optimize growth and intellectual development in affected fetuses. We herein report a case of fetal treatment in two successive siblings showing in utero hyperthyroid status in a woman with a history of ablative treatment for Graves' disease. The fetuses were considered in hyperthyroid status based on high levels of maternal TRAb, a goiter, and persistent tachycardia. In particular, cardiac failure was observed in the second fetus. With intrauterine treatment using potassium iodine and propylthiouracil, fetal cardiac function improved. A high level of TRAb was detected in the both neonates. To the best of our knowledge, this is the first report on the changes of fetal cardiac function in response to fetal treatment in two siblings showing in utero hyperthyroid status. This case report illustrates the impact of prenatal medication via the maternal circulation for fetal hyperthyroidism and cardiac failure.

The aim of this study is to explore beta cell dysfunction and its clinical significance in gestational diabetes mellitus (GDM). We assessed insulin sensitivity and insulin secretion in a total of 277 Japanese women between 24 and 27 weeks of pregnancy who underwent a 2 h, 75 g oral glucose tolerance test (OGTT) because of an abnormal result on a 1 h 50 g oral glucose challenge conducted as part of a standard screening for GDM. Insulin sensitivity was evaluated by an insulin sensitivity index derived from OGTT (ISOGTT), whereas insulin secretion was calculated as a ratio of the total area under the insulin curve to the total area under the glucose curve (AUCins/glu). Beta cell function in relation to insulin sensitivity (i.e. disposition index) was derived from the product of insulin sensitivity and insulin secretion (i.e. AUCins/glu × ISOGTT). In women diagnosed with GDM (n=57), the disposition index was significantly lower than that in those without GDM, irrespective of obesity. The disposition index in women with GDM was significantly correlated with levels of fasting and mean preprandial capillary glucose and HbA1c before initiating insulin therapy (r = -0.45, -0.38, -0.49, respectively). Furthermore, there was a significant correlation between the disposition index and total insulin dosage to achieve glycemic goal (r = -0.41). In conclusion, we demonstrated beta cell dysfunction in Japanese women with GDM irrespective of obesity. The level of beta cell dysfunction in GDM was associated with the severity of glucose intolerance and total insulin dosage required. These findings underpin clinical significance of beta cell dysfunction in GDM.

Hypophosphatasia (HPP) is an autosomal recessive metabolic disorder with impaired bone mineralization due to mutations in the ALPL gene. The genotype-phenotype correlation of this disorder has been widely described. Here, we present two affected siblings, whose fetal phenotypes were discordant. A 31-year-old Japanese woman, G0P0, was referred to our institution because of fetal micromelia. After obstetric counseling, the pregnancy was terminated at 21 weeks’ gestation. Post-mortem radiographs demonstrated severely defective mineralization of the skeleton. The calvarial, spinal, and tubular bones were mostly missing. Only the occipital bones, mandible, clavicles, ribs, one thoracic vertebra, ilia, and tibia were relatively well ossified. The radiological findings suggested lethal HPP. Genetic testing for genomic DNA extracted from the umbilical cord identified compound heterozygous mutations in the ALPL gene (c.532T>C, p.Y178H; c.1559delT, p.Leu520Argfs*86). c.532T>C was a novel variant showing no residual activity of the protein by the functional analysis. The parents were heterozygous carriers. In the next pregnancy, biometric values on fetal ultrasonography at 20 and 26 weeks’ gestation were normal. At 34 weeks, however, a small chest and shortening of distal long bones came to attention. The neonate delivered at 41 weeks showed serum ALP of <5U/L. Radiological examination showed only mild thoracic hypoplasia and metaphyseal mineralization defects of the long bones. ALP replacement therapy was introduced shortly after birth, and the neonate was discharged at day 22 without respiratory distress. Awareness of discordant fetal phenotypes in siblings with HPP precludes a diagnostic error, and enables early medical intervention to mildly affected neonates.

The cover image, by Satoru Ikenoue et al., is based on the Clinical Report Discordant fetal phenotype of hypophosphatasia in two siblings, DOI: 10.1002/ajmg.a.38531.

Aims/Introduction: Risk factors of type 2 diabetes mellitus in Japanese women with recent gestational diabetes mellitus are unknown. The objective of the present study was to investigate the clinical and genetic characteristics associated with postpartum abnormal glucose tolerance in Japanese women with gestational diabetes mellitus. Materials and Methods: A total of 213 Japanese women with recent gestational diabetes mellitus who underwent a postpartum 2-h oral glucose tolerance test were investigated. The association between antepartum clinical characteristics and postpartum abnormal glucose tolerance (diabetes or prediabetes based on the Japan Diabetes Society criteria) was examined. Frequencies of 45 known type 2 diabetes mellitus-associated genetic variants were also compared between women with and without postpartum abnormal glucose tolerance. Results: A total of 59 women showed postpartum abnormal glucose tolerance (prediabetes, n = 51; diabetes, n = 8). Plasma glucose levels at 1 or 2 h, the insulinogenic index and the insulin secretion-sensitivity index-2 of the antepartum oral glucose tolerance test were independent of postpartum abnormal glucose tolerance risk factors (P = 0.006, P = 0.00002, P = 0.01 and P = 0.006, respectively). Four genetic variants (rs266729 [ADIPOQ], rs6017317 [HNF4A], rs5215 [KCNJ11] and rs7177055 [HMG20A]) showed a nominally significant association with postpartum abnormal glucose tolerance (P < 0.05, respectively). Among these, three were related to insulin secretion. Postpartum abnormal glucose tolerance risk significantly increased with increasing risk-allele number (P = 0.0005; odds ratio 1.91). Conclusions: Clinical features and genetic variants related to impaired insulin secretion are risk factors of postpartum abnormal glucose tolerance in Japanese women with recent gestational diabetes mellitus.

Background: Newborns exhibit substantial variation in gestational age-adjusted and sex-adjusted fat mass proportion. The antecedent characteristics of fetal body composition that are associated with newborn fat mass proportion are poorly understood. Objective: The aim of this study was to determine whether a composite measure of fetal fat mass is prospectively associated with newborn adiposity. Methods: In a longitudinal study of 109 low-risk pregnancies, fetal ultrasonography was performed at approximately 12, 20 and 30 weeks gestation. Estimated fetal adiposity (EFA) was derived by integrating cross-sectional arm and thigh per cent fat area and anterior abdominal wall thickness. Newborn per cent body fat was quantified by Dual Energy X-Ray Absorptiometry. The association between EFA and newborn per cent body fat was determined by multiple linear regression. Results: After controlling for confounding factors, EFA at 30 weeks was significantly associated with newborn per cent body fat (standardized β = 0.41, p < 0.001) and explained 24.0% of its variance, which was substantially higher than that explained by estimated fetal weight (8.1%). The observed effect was driven primarily by arm per cent fat area. Conclusions: A composite measure of fetal adiposity at 30 weeks gestation may constitute a better predictor of newborn per cent body fat than estimated fetal weight by conventional fetal biometry. Fetal arm fat deposition may represent an early indicator of newborn adiposity. After replication, these findings may provide a basis for an improved understanding of the ontogeny of fetal fat deposition, thereby contributing to a better understanding of its intrauterine determinants and the development of potential interventions.