Gestational Weight Gain Growth Charts Adapted to Japanese Pregnancies Using a Bayesian Approach in a Longitudinal Study: The Japan Environment and Children's Study.

BACKGROUND: Tracking gestational weight gain (GWG) during pregnancy makes it possible to optimize pregnancy outcomes, and GWG growth curves are well suitable for this purpose. The GWG guidelines for Japanese were revised in 2021. However, currently, there are no GWG growth curves to guide women on how to gain weight to meet these guidelines. METHODS: Using data on 96,631 live births from the Japan Environment and Children's Study (JECS), we created descriptive GWG percentile curves estimating the trajectory of GWG required to meet the GWG guidelines stratified by pre-pregnancy body mass index (BMI). For both analyses, Bayesian mixed models with restricted cubic splines adjusted for maternal characteristics were used. RESULTS: GWG curves substantially differed by pre-pregnancy BMI and were higher among multiparas and those with lower maternal age and with no previous disease. We estimated that underweight, normal weight, overweight, and obese women who gain 8.4 to 11.1 kg, 6.4 to 9.1 kg, 3.8 to 6.5 kg, and <1.9 kg at 30 weeks of gestation are on the trajectory to reach the new guidelines at 40 weeks of gestation. CONCLUSION: We provide GWG percentiles curves for Japanese women, as well as GWG trajectory curves to meet the new GWG recommendations. These results may help pregnant women monitor weight during pregnancy.

Lack of catch-up in weight gain may intermediate between pregnancies with hyperemesis gravidarum and reduced fetal growth: the Japan Environment and Children's Study.

BACKGROUND: Women with nausea and vomiting of pregnancy (NVP) have higher birth weight infants, while those with hyperemesis gravidarum, a severe manifestation of NVP, have lower birth weight infants. We aimed to investigate the associations between maternal weight loss (a consequence of hyperemesis gravidarum), NVP, and infant birth weight. METHODS: This study was a secondary analysis of a nationwide birth cohort in Japan. Singleton pregnancies delivered at 28-41 weeks of gestation were included in the analysis. Women were categorized based on their weight change in the 1st trimester (as a proportion to their pre-pregnancy weight: > + 3%, > 0 to + 3%, > -3 to 0%, > -5 to -3%, ≤ -5%) and severity of NVP (no nausea, only nausea, vomiting but able to eat, vomiting and unable to eat). The effects of weight change and severity of NVP on infant birth weight and small for gestational age (SGA) were assessed using regression models. We further examined how these effects could be modified by maternal weight gain up to the 2nd trimester. RESULTS: Among 91,313 women, 5,196 (5.7%) lost ≥ 5% of their pre-pregnancy weight and 9,983 (10.9%) experienced vomiting and were unable to eat in the 1st trimester. Women with weight loss ≥ 5% in the 1st trimester had infants 66 (95% CI: 53, 78) g lighter and higher odds of SGA (aOR: 1.29; 95% CI: 1.14, 1.47) than women who gained > 3% during the same period. However, when adjusting for weight gain up to the 2nd trimester, women with weight loss ≥ 5% in the 1st trimester had infants 150 (95% CI: 135, 165) g heavier and lower odds of SGA (aOR: 0.39; 95% CI: 0.33, 0.46) than those who gained > 3% during the same period. In contrast, women with more severe NVP tended to have infants with larger birth weight and lower odds of SGA compared to women without NVP. These trends were strengthened when adjusting for weight gain up to the 2nd trimester. CONCLUSIONS: Our study suggests the possibility that reduced fetal growth in pregnancies with hyperemesis gravidarum may be caused by the lack of catch-up in gestational weight gain up to the 2nd trimester.

Maternal sleep duration and neonatal birth weight: the Japan Environment and Children's Study.

BACKGROUND: The adequate maternal sleep duration required for favorable obstetric outcomes is unknown. We evaluated the association between maternal sleep duration and low birth weight infants, small for gestational age infants, and macrosomia. METHODS: Participants enrolled in the Japan Environment and Children's Study, a nationwide birth cohort study, with singleton pregnancies after 22 weeks, who gave birth between 2011 and 2014 were enrolled and categorized into five groups according to maternal sleep duration during pregnancy: < 6.0 h, 6.0-7.9 h, 8.0-8.9 h, 9.0-9.9 h, and 10.0-12.0 h. We evaluated the association between maternal sleep duration and the incidence of low birth weight infants (< 2500 g), very low birth weight infants (< 1500 g), small for gestational age infants, and macrosomia (> 4000 g), with women with maternal sleep duration of 6.0-7.9 h as the reference, using a multiple logistic regression model. RESULTS: In total, 82,171 participants were analyzed. The adjusted odds ratios (95% confidence intervals) for low birth weight infants in women with maternal sleep duration of 9.0-9.9 h and 10.0-12.0 h and for small for gestational age infants in women with maternal sleep duration of 9.0-9.9 h were 0.90 (0.83-0.99), 0.86 (0.76-0.99), and 0.91 (0.82-0.99), respectively, before adjusting for excessive gestational weight gain. No significant association was observed between maternal sleep duration and these outcomes after adjusting for excessive gestational weight gain. Among women with appropriate gestational weight gain, the adjusted odds ratios (95% confidence intervals) for low birth weight infants and for small for gestational age infants with sleep duration of 9.0-9.9 h were 0.88 (0.80-0.97) and 0.87 (0.78-0.97), respectively. CONCLUSIONS: Maternal sleep duration of 9.0-9.9 h was significantly associated with the decreased incidence of low birth weight infants and small for gestational age infants in pregnant women with appropriate gestational weight gain, compared with that of 6.0-7.9 h. Care providers should provide proper counseling regarding the association between maternal sleep duration and neonatal birth weight and suggest comprehensive maternal lifestyle modifications to prevent low birth weight and small for gestational age infants.

Associations Between Metal Levels in Whole Blood and IgE Concentrations in Pregnant Women Based on Data From the Japan Environment and Children's Study.

BACKGROUND: Metal exposures could possibly affect allergic responses in pregnant women, although no studies have yet shown a clear relationship between the two, and such exposures might also affect the development of allergic diseases in children. METHODS: We investigated the relationship between metal concentrations in whole blood and immunoglobulin E (IgE; total and specific) in 14,408 pregnant women who participated in the Japan Environment and Children's Study. The subjects submitted self-administered questionnaires, and blood samples were collected from them twice, specifically, during the first trimester and again during the second/third trimester. Concentrations of the metals Cd, Pb, Hg, Se, and Mn, as well as serum total and allergen-specific IgEs for egg white, house dust-mites (HDM), Japanese cedar pollen (JCP), animal dander, and moth, were measured. Allergen-specific IgE(s) were divided based on concentrations <0.35 or ≥0.35 UA/mL, and the metal levels were divided into quartiles. RESULTS: Multivariable logistic regression analysis showed that there was a significant negative correlation between HDM- and animal dander-specific IgEs and Hg and Mn concentrations. Conversely, there was a significant positive relationship between JCP-specific IgE and Hg and Se concentrations. CONCLUSIONS: Metal exposures may be related to both increases and decreases in allergen-specific IgEs in pregnant women.

Impact of sleep duration during pregnancy on the risk of gestational diabetes in the Japan environmental and Children's study (JECS).

BACKGROUND: Gestational diabetes mellitus (GDM) has serious effects on both mother and child. Like Type 2 Diabetes Mellitus, it is increasing in prevalence world-wide. In addition to obesity, sleep duration has been named an important risk factor. Using a large cohort study, including data from 48,787 participants of the Japan Environment and Children's Study (JECS), we examined the association between sleep duration and both random blood glucose levels and GDM rates during pregnancy. METHODS: Random blood glucose levels were measured during pregnancy. GDM diagnosis was based on the results of 75 g oral glucose tolerance test. Additional anthropometric data was collected from questionnaires for statistical analysis. RESULTS: Compared to mothers averaging 7 to < 10 h sleep (reference group), women receiving < 5 h or ≥ 10 h sleep exhibited significantly elevated random blood glucose levels. This was associated with an elevated risk for positive GDM screening (< 5 h sleep: OR 1.17 (0.96-1.44) p = 0.126; ≥10 h sleep: OR 1.13 (1.03-1.25) p = 0.006). Calculating the risk for GDM, women sleeping < 5 h or ≥ 10 h exhibited elevated risks of 1.31-fold and 1.21 respectively. However, this trend was not found to be significant. CONCLUSIONS: Sleep is a critical factor in glucose metabolism, with both abnormally long and short sleep duration increasing random blood glucose levels in pregnant women. Moreover, the risk for positive GDM screening increases significantly with elevated sleep, ≥10 h per night. These findings are promising because they support the idea that sleep duration is a modifiable risk factor, and can be focused upon to improve health and pregnancy outcome.

Gestational age-related changes in shear wave speed of the uterine cervix in normal pregnancy at 12-35 weeks' gestation.

Background This study aimed to analyze age-related changes in shear wave speed (SWS) of the normal uterine cervix. Methods We studied 362 women with a normal singleton pregnancy at 12-35 weeks' gestation. The SWS of the cervix was measured using transvaginal ultrasonography at the internal os region of the anterior cervix (IOA), posterior cervix (IOP) and cervical canal (IOC), and at the external os region of the anterior cervix (EOA), posterior cervix (EOP) and cervical canal (EOC). The following parameters were analyzed: (1) time trend of SWS of the individual sampling points, (2) comparison of SWS in the internal cervical region and SWS in the external cervical region, and (3) comparison of SWS between the internal and external cervical regions. Statistical analyses were performed using mixed-effects models. Results The SWS of IOP decreased in bilinear regression, with a critical change in the rate at 22 weeks, whereas the SWS of the remaining points decreased linearly. The estimated values of SWS of IOP at 84, 154 and 251 days were higher than those of IOA and IOC (P<0.001). The estimated values of SWS of IOP at 84 and 154 days were higher than those of EOP (P<0.001). Significant differences between IOP and EOP were shown until 244 days (P<0.05). The estimated value of SWS of IOC at 84 days was higher than that of EOC (P<0.001). Significant differences between IOC and EOC were shown until 210 days (P<0.05). Conclusion The SWS of the uterine cervix in pregnancy decreases with advancing gestation. The SWS of IOP had the highest value among the sampling points with unique characteristics.

Associations between metal concentrations in whole blood and placenta previa and placenta accreta: the Japan Environment and Children's Study (JECS).

BACKGROUND: Placenta previa and placenta accreta associate with high morbidity and mortality for both mothers and fetus. Metal exposure may have relationships with placenta previa and placenta accreta. This study analyzed the associations between maternal metal (cadmium [Cd], lead [Pb], mercury [Hg], selenium [Se], and manganese [Mn]) concentrations and placenta previa and placenta accreta. METHODS: We recruited 17,414 women with singleton pregnancies. Data from a self-administered questionnaire regarding the first trimester and medical records after delivery were analyzed. Maternal blood samples were collected to measure metal concentrations. The subjects were classified into four quartiles (Q1, Q2, Q3, and Q4) according to metal concentrations. RESULTS: The odds ratio for placenta previa was significantly higher among subjects with Q4 Cd than those with Q1 Cd. The odds ratio for placenta previa was significantly higher for subjects with Q2 Pb than those with Q1 Pb. CONCLUSION: Participants with placenta previa had higher Cd concentrations. However, this study was cross-sectional and lacked important information related to Cd concentration, such as detailed smoking habits and sources of Cd intake. In addition, the subjects in this study comprised ordinary pregnant Japanese women, and it was impossible to observe the relationship between a wide range of Cd exposure and placenta previa. Therefore, epidemiological and experimental studies are warranted to verify the relationship between Cd exposure and pregnancy abnormalities.

Optimal protein intake during pregnancy for reducing the risk of fetal growth restriction: the Japan Environment and Children's Study.

Clinical trials show that protein supplement increases infant size in malnourished populations; however, epidemiological studies in high-income countries have reported mixed results. Although these findings suggest a non-linear relationship between maternal macronutrient intake and fetal growth, this relationship has not been closely examined. We assessed the association between maternal protein intake and fetal growth among 91 637 Japanese women with singletons in a nation-wide cohort study using validated FFQ. The respondents answered the FFQ twice, once during early pregnancy (FFQ1; 16·3 (sd 6·0) weeks), and second during mid-pregnancy (FFQ2, 28·1 (sd 4·1) weeks). Daily energy intake and percentage energy from protein, fats and carbohydrates were 7477 (sd 2577) kJ and 13·5 (sd 2·0), 29·5 (sd 6·5) and 55·3 (sd 7·8) %, respectively, for FFQ1, and 7184 (sd 2506) kJ and 13·6 (sd 2·1), 29·8 (sd 6·6) and 55·3 (sd 7·9) %, respectively, for FFQ2. The average birth weight was 3028 (sd 406) g, and 6350 infants (6·9 %) were small for gestational age (SGA). In both phases of the survey, birth weight was highest and the risk of SGA was lowest when the percentage energy from protein was 12 %, regardless of whether isoenergetic replacement was with fat or carbohydrates. Furthermore, when protein density in the maternal diet was held constant, birth weight was highest when 25 % of energy intake came from fat and 61 % came from carbohydrates during early pregnancy. We found maternal protein intake to have an inverse U-curve relationship with fetal growth. Our results strongly suggest that the effect of protein on birth weight is non-linear, and that a balanced diet fulfilling the minimum requirement for all macronutrients was ideal for avoiding fetal growth restriction.

The association between whole blood concentrations of heavy metals in pregnant women and premature births: The Japan Environment and Children's Study (JECS).

BACKGROUND: Heavy metals are widely distributed in the environment. Recent reports have demonstrated the risk of preterm birth following heavy metal exposure. Preterm births are classified as early and late, depending on the duration of pregnancy, and are associated with increased risk of congenital illnesses such as heart failure, asthma, etc. Particularly, early preterm births carry a higher risk of mortality; however, the differential effects of heavy metal exposure on early and late preterm births are unknown. OBJECTIVES: To analyze the association between maternal whole blood concentrations of heavy metals, such as cadmium (Cd), lead (Pb), mercury (Hg), selenium (Se), and manganese (Mn) that are common toxicants in Japan, and early and late preterm births. METHODS: The data of 14,847 pregnant women who were participants of the Japan Environment and Children's Study were used. Data of the self-questionnaire pertaining to the first trimester (T1), second/third trimester (T2), and medical records after delivery were analyzed. We divided preterm birth into two groups: early preterm (22 to < 34 weeks) and late preterm (34 to < 37 weeks). Maternal blood samples for measuring heavy metal concentrations were collected in T2 (pregnancy weeks: 14-39). The participants were classified into four quartiles (Q1-Q4) according to increasing heavy metal levels. RESULTS: The rate of preterm birth was 4.5%. After controlling for confounding factors, such as age, pre-pregnancy body mass index, smoking, partner's smoking, drinking habits, gravidity, parity, number of cesarean deliveries, uterine infections, household income, educational levels, and sex of infant, Cd levels were found, by multivariable logistic regression analysis, to be significantly associated with early preterm birth (p = 0.002), with odds ratio for early preterm birth of 1.91 (95% confidence interval: 1.12-3.27, P = 0.018) in subjects of Q4 compared with in subjects with term birth (≧ 37 weeks). CONCLUSION: Maternal blood Cd levels during pregnancy are positively associated with the risk of early preterm birth among Japanese women. Identification of the main source of maternal Cd exposure may contribute to the prevention of early preterm births and health maintenance of mothers and their infants in the future.

Factors associated with occupation changes after pregnancy/delivery: result from Japan Environment & Children's pilot study.

BACKGROUND: In Japan, although the number of females who continue to work after marriage has recently increased, the proportion of those working while parenting their infants is still not clearly increasing, indicating that it is still difficult for them to continue working after delivery. The present study aimed to clarify factors influencing females' continuation of work, using data obtained by continuously following up the same subjects and focusing on occupation changes, family environments, and the type of employment after pregnancy or delivery. METHODS: Based on the results of the questionnaire survey, which was conducted involving 164 participants at 4 universities, as part of the Japan Environment and Children's Pilot Study (JECS Pilot Study) led by the Ministry of Environment and the National Institute for Environmental Studies, the occupational status was compared between the detection of pregnancy (weeks 0 to 7) and 1 year after delivery. RESULTS: compared with changed their occupations significantly more frequently (OR = 5.07, 95% CI = 2.57-10.01, P < 0.001). Furthermore, on examining in detail, occupation changes were particularly marked among (OR = 12.48, 95% CI = 4.43-35.15, P < 0.001). This tendency was especially shown among < > (OR = 10.36, 95% CI = 1.59-67.38, P = 0.014) and < > (OR = 15.15, 95% CI = 2.55-90.17, P = 0.003). CONCLUSIONS: Analysis revealed that the type of employment, rather than the category of occupation, was associated with the continuation of work after pregnancy or delivery more closely, as compared with continued to work less frequently. Furthermore, on comparison of the category of occupation among , < > and < > were shown to be more likely to continue to be engaged in the same occupation after pregnancy or delivery. These differences may be related to availability of the child-care leave program and other support resources, therefore, it may be important to establish social systems that enable all females, to use these support resources if they wish, and actively work, while delivering and parenting their children.

Simplified Wide-Range Ultrasonic Measurements Using the Sensor Three-Dimensional System.

We developed a simplified three-dimensional ultrasonic device that can scan a wide area and performed measurements in the scanned area. The system is more compact than magnetic resonance imaging (MRI) systems and can measure random cross sections by acquiring volume data over a wide range through freehand scanning with a magnetic sensor unit that detects the transducer position. The system was applied successfully to a case with a huge myoma. Our system, in ways similar to computed tomography or MRI systems, can support both the objective understanding of the pathology of huge tumors and follow-up determinations of tumor diameters at arbitrary cross sections in the volume data.

Air Pollutant Exposure Within a Few Days of Delivery and Placental Abruption in Japan.

BACKGROUND: Placental abruption is an emergency obstetric complication. Although the etiology of abruption is not fully understood, acute stimuli, such as ischemia and/or inflammation, are associated with rupture of the decidual artery, resulting in placental separation. Ischemia and inflammation are acute biologic effects of air pollution. Using a case-crossover design, we tested the hypothesis that a short-term increase in exposure to air pollutants is a potential trigger of placental abruption. METHODS: We received data for western Japan (Kyushu-Okinawa Districts) from the Japan Perinatal Registry Network database. From 2005 to 2010, 821 singleton pregnant women with placental abruption were identified. We assigned daily concentrations of air pollutants, including nitrogen dioxide (NO2), suspended particulate matter, ozone, and sulfur dioxide (SO2), from the nearest monitoring station to the respective delivery hospital of each woman. Because information on the onset day of abruption was not obtained, we assumed the case day to be 1 day before the day of delivery. RESULTS: Exposure to NO2 at 2 days' lag was associated with placental abruption (temperature adjusted odds ratio per 10 ppb increase = 1.4; 95% confidence interval = 1.1, 1.8). The association patterns were similar, when we restricted to participants who delivered by emergency cesarean (1.4, 1.1, 1.9), or who delivered after 35 weeks of gestation (1.4, 1.0, 2.0). There was no association with suspended particulate matter, ozone, or SO2. CONCLUSIONS: We observed an association between NO2 exposure at 2 days before the day of delivery and placental abruption in pregnant Japanese women.

Comparison between air pollution concentrations measured at the nearest monitoring station to the delivery hospital and those measured at stations nearest the residential postal code regions of pregnant women in Fukuoka.

BACKGROUND: Numerous earlier studies examining the association of air pollution with maternal and foetal health estimated maternal exposure to air pollutants based on the women's residential addresses. However, residential addresses, which are personally identifiable information, are not always obtainable. Since a majority of pregnant women reside near their delivery hospitals, the concentrations of air pollutants at the respective delivery hospitals may be surrogate markers of pollutant exposure at home. We compared air pollutant concentrations measured at the nearest monitoring station to Kyushu University Hospital with those measured at the closest monitoring stations to the respective residential postal code regions of pregnant women in Fukuoka. METHODS: Aggregated postal code data for the home addresses of pregnant women who delivered at Kyushu University Hospital in 2014 was obtained from Kyushu University Hospital. For each of the study's 695 women who resided in Fukuoka Prefecture, we assigned pollutant concentrations measured at the nearest monitoring station to Kyushu University Hospital and pollutant concentrations measured at the nearest monitoring station to their respective residential postal code regions. RESULTS: Among the 695 women, 584 (84.0%) resided in the proximity of the nearest monitoring station to hospital or one of the four other stations (as the nearest stations to their respective residential postal code region) in Fukuoka city. Pearson's correlation for daily mean concentrations among the monitoring stations in Fukuoka city was strong for fine particulate matter (PM2.5), suspended particulate matter (SPM), and photochemical oxidants (Ox) (coefficients ≥0.9), but moderate for coarse particulate matter (the result of subtracting the PM2.5 from the SPM concentrations), nitrogen dioxide, and sulphur dioxide. Hospital-based and residence-based concentrations of PM2.5, SPM, and Ox were comparable. CONCLUSIONS: For PM2.5, SPM, and Ox, exposure estimation based on the delivery hospital is likely to approximate that based on the home of pregnant women.

Comparative study on three different methods for arm-span measurement: the Japan environment and Children's study pilot.

BACKGROUND: Arm span is an important measure for the assessment of growth and hormone deficiency diseases. In an epidemiological survey, with a large number of subjects' indicators, it is especially valuable to establish methods which can measure both quickly and accurately. However, there are various methods, and the length of arm span may vary according to the medical institution. METHODS: The arm span of nine 6-year old subjects was measured using two institutional standard methods, A and B, and a third method C which is an improved method and has been used for the first time in this study. A, No-Wall, with heels together the child stretches the arms out to the sides. B, Wall & No-Line, the child stands against the wall with heels together and spreads the arms against the wall. C, Wall & Line, the method is the same as B except a paper with horizontal lines is placed on the wall. We measured twice by each method. RESULTS: The difference between the 1st and 2nd measurements was marginally significantly smaller by using method of C. CONCLUSION: The method C, which we improved, is the best way to measure arm span.

Relationship between hyperemesis gravidarum and small-for-gestational-age in the Japanese population: the Japan Environment and Children's Study (JECS).

BACKGROUND: Small-for-gestational-age in infancy is a known risk factor not only for short-term prognosis but also for several long-term outcomes, such as neurological and metabolic disorders in adulthood. Previous research has shown that severe nausea and vomiting in early pregnancy (NVP) and hyperemesis gravidarum, which is an extreme form of NVP, represent risk factors for small-for-gestational-age birth. However, there is no clear consensus on this association. Thus, in the present study, we investigated the correlation between hyperemesis gravidarum and NVP on the one hand, and infant birth weight on the other, using data from the Japan Environment and Children's Study (JECS). METHODS: The data utilized in the present study were obtained from the JECS, an ongoing cohort study that began in January 2011. Our sample size was 8635 parent-child pairs. The presence or absence of severe NVP, hyperemesis gravidarum, and potential confounding factors were noted. A multivariable regression analysis was used to estimate risks for small-for-gestational-age birth, and the results were expressed as risk ratios and 95 % confidence intervals. RESULTS: The risk ratios of small-for-gestational-age birth (95 % confidence interval) for mothers with severe NVP and those with hyperemesis gravidarum were 0.86 (0.62-1.19) and 0.81 (0.39-1.66), respectively, which represents a non-significant result. CONCLUSIONS: In our analysis of JECS data, neither severe NVP nor hyperemesis gravidarum was associated with increased risk for small-for-gestational-age birth.

Analysis of antenatal-onset cerebral palsy secondary to transient ischemia in utero using a national database in Japan.

AIM: We conducted a retrospective analysis of summary medical reports of children diagnosed with cerebral palsy (CP) to identify clinical features of antenatal onset of CP secondary to transient ischemia in utero. METHODS: The 658 brief summary reports available in the Japan Obstetric Compensation System for Cerebral Palsy were screened, and we identified cases of singleton pregnancy, delivered at gestational age ≥ 33 weeks and those with cord blood gas pH ≥ 7.20. Of the 137 cases identified, 84 were excluded for the following reasons: no evidence of ischemic brain lesion, clear post-natal causative factor of CP, presence of a congenital condition, and sentinel hypoxic event, such as uterine rupture. The demographic profiles of the 53 cases included in our analysis were compared to identify those with and without an abnormal variability in fetal heart rate. RESULTS: Between-group comparison identified an association between abnormal heart rate variability and a lower Apgar score at 1 min (2 vs 6; P < 0.001) and 5 min (5.5 vs 8; P = 0.002), and more frequent episodes of fetal movement loss (41% vs 10%; P = 0.027). An hypoxic event ≤ 1 week before delivery was more likely to be associated with abnormal heart rate variability (89%) and low Apgar score (82%), while events at > 1 week were associated with development of polyhydramnios (44%). CONCLUSION: In utero transient ischemic events can contribute to term or near-term CP. Careful follow-up is recommended for fetuses with a history of fetal movement loss, abnormal variability in heart rate, and polyhydramnios of unknown causes.

A register-based study of the association between air pollutants and hypertensive disorders in pregnancy among the Japanese population.

BACKGROUND: Ambient air pollution is hypothesized to be a risk factor for hypertensive disorders in pregnancy, one of the major pregnancy complications. Past studies have reported the supporting evidence, however this mainly referred to the Western population, and results from trimester-specific analysis have been varied. In this study, we focused on exposure during the first trimester of pregnancy (placental development stage), and tested the hypothesis among the Japanese population. METHODS: We drew on data from the Japan Perinatal Registry Network database, and studied 36,620 singleton pregnant women without medical complications, in western Japan (Kyushu and Okinawa districts) between 2005 and 2010. In addition, data on ozone, suspended particulate matter (SPM), nitrogen dioxide (NO2), and sulfur dioxide (SO2) concentrations were obtained. The nearest monitoring station to the respective birthing hospital was used as a reference point for assigning average concentrations of each pollutant during the first trimester of pregnancy for each woman. The logistic regression model was applied to assess the association between quintiles of each pollutant and hypertensive disorders in pregnancy. RESULTS: Mean concentrations during the first trimester were 41.3 ppb for ozone, 27.4 µg/m(3) for SPM, 11.8 ppb for NO2, and 3.2 ppb for SO2. High exposure to ozone was associated with an increased risk of hypertensive disorders in pregnancy (for highest quintile vs. lowest: odds ratio=1.20, 95% confidence interval=1.01-1.42). With regard to SPM, NO2 and SO2, we did not obtain the results with constant directionality. CONCLUSIONS: Ozone exposure during early pregnancy may be a risk factor for hypertensive disorders in pregnancy.

Clinical Significance of Prenatal and Postnatal Heavily T2-Weighted Magnetic Resonance Images in Patients with Myelomeningocele.

PURPOSE: To compare the utility and limitations of prenatal magnetic resonance (MR) imaging using half-Fourier acquisition single-shot turbo spin-echo (HASTE) with postnatal heavily T2-weighted imaging (hT2WI) for the evaluation of central nervous system abnormalities associated with myelomeningocele (MMC). METHODS: Sixteen patients with MMC who had undergone pre- and postnatal MR imaging were included in this study. MR imaging, including HASTE, was undertaken in the 3rd trimester, and hT2WI was performed immediately after delivery. The precision with which each could distinguish MMC, hindbrain herniation and ventriculomegaly was compared retrospectively. RESULTS: The skin defects and MMC sacs were clearly visible on prenatal HASTE images, although it was difficult to identify precisely the level of MMC compared with postnatal hT2WI, in which the detailed anatomical relationships of the spinal cord, neural placode and ventral nerve roots were evident in every case. Hindbrain herniation could be visualized on prenatal HASTE images, although its severity was difficult to evaluate because of the small size of the structures and neck flexion; again, the resolution was superior on postnatal hT2WI. For hydrocephalus, there were no significant differences in the diagnostic precision and ability to grade the severity between pre- and postnatal imaging. CONCLUSION: Prenatal HASTE imaging permits the diagnosis and understanding of the gross anatomy of MMC and associated hindbrain herniation and ventriculomegaly, but postnatal hT2WI is superior for evaluating detailed anatomy.

Compilation of copy number variants identified in phenotypically normal and parous Japanese women.

With increasing public concern about infertility and the frequent involvement of chromosomal anomalies in miscarriage, analyses of copy number variations (CNVs) have been used to identify the genomic regions responsible for each process of childbearing. Although associations between CNVs and diseases have been reported, many CNVs have also been identified in healthy individuals. Like other types of mutations, phenotypically indefinite CNVs may have been retained and accumulated during anthropogenesis. Therefore to distinguish causative variants from other variants is a formidable task. Furthermore, because previous studies have predominantly focused on European and African populations, comprehensive detection of common Asian CNVs is eagerly awaited. Here, using a high-resolution genotyping array and samples from 411 Japanese women with normal parity without significant complications, we have compiled 1043 copy number variable regions. In total, the collected regions cover 164 Mb, or up to 0.5% of the genome. The copy number differences in these regions may be irrelevant not only to infertility but also to a wide range of diseases. The utility of this resource in reducing the candidate pathogenetic variants, especially in Japanese subjects, is also demonstrated.

Effectiveness of preventive parental education delivered from pregnancy to 1 month postpartum for improving infant sleep and parental sleep and depression: a systematic review protocol.

OBJECTIVE: This review aims to evaluate the effectiveness of preventive parental education on infant sleep problems, delivered from pregnancy to 1 month postpartum, on infant sleep, postpartum parental sleep, and depression. INTRODUCTION: Infant sleep problems are likely to persist into childhood if not treated and are associated with difficulties in later development. Parents of children with sleep problems had lower sleep quality and emotional regulation than those without sleep problems. Chronic sleep deprivation and fragmentation increases the risk of maternal depression. Therefore, preventive parental education regarding infant sleep problems can improve the long-term well-being of both children and their parents. INCLUSION CRITERIA: Experimental and quasi-experimental study designs, including preventive parental education about infant sleep problems delivered from pregnancy to 1 month postpartum, will be considered. The outcomes will be infants' sleep, postpartum parental sleep, and parental depression. METHODS: MEDLINE (Ovid), CINAHL (EBSCOhost), PsycINFO (Ovid), the Cochrane Central Register of Controlled Trials, and Igaku Chuo Zasshi (Japan Medical Abstracts Society) will be searched without restrictions on language or date of publication. Eligible studies will be critically appraised, and data will be extracted by 2 independent reviewers using the JBI methodology. The studies will be pooled for statistical meta-analysis. Where statistical pooling is not possible, the findings will be presented in narrative format. We will use the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to assess the certainty in the quality of evidence. REVIEW REGISTRATION: PROSPERO CRD42023430562.