Michihiro Kamijima

Nagoya City University | NCU · Department of Occupational and Environmental Health

Background Although involvement of toddlers in swimming activities has increased recently, information regarding the impact of swimming during toddlerhood on subsequent child motor competence development is scarce. This study aimed to determine how swimming experience, particularly the timing of initiation and the continuity of swimming activities...

Background: Although recent in vitro experimental results have raised the question of whether maternal exposure to per- and polyfluoroalkyl substances (PFAS) may be a potential environmental risk factor for chromosomal abnormalities, epidemiological studies investigating these associations are lacking. Objectives: This study examined whether pre...

Background and Aims In the neurobiological theory of attention, the orienting network mainly supports the temperamental regulatory function in infancy, with soothing methods such as visual attention distraction influencing its development. The attention distraction method chosen for soothing is thought to be influenced by maternal sensitivity, whic...

Background: Poor oral hygiene, generally manifesting as dental caries, gingivitis, or periodontitis, is a common chronic condition among both children and adults worldwide and has been reportedly associated with hypertension and arterial stiffness mainly in adult patients. However, these associations have not been well-studied in children and adult...

This study aimed to evaluate the association between atopic dermatitis in pregnant women and preterm births, accounting for maternal ritodrine hydrochloride administration status. Data of 83,796 women with singleton pregnancies at and after 22 weeks of gestation (enrolled between 2011 and 2014) were analyzed. These data were obtained from the Japan...

There are few studies on the parenting of fathers with autism traits. To investigate this issue, we examined the type of parenting performed by fathers with autism traits using data from a nationwide birth cohort study, the Japan Environment and Children’s Study. Paternal parenting was evaluated by mothers or caregivers when the child was 2 years o...

Context Women with polycystic ovary syndrome (PCOS), which is the most common endocrine disorder in women of reproductive age, have a potentially increased risk of gestational diabetes mellitus (GDM). Objective To examine the impact of PCOS on GDM based on maternal body mass index (BMI) using data from a large birth cohort study in Japan. Design...

Hypertensive disorders of pregnancy (HDP) increase the risk of preterm births and cesarean delivery. This study aimed to investigate whether maternal blood leukocyte, monocyte, or neutrophil counts in the first trimester are related to the development of HDP. Data were collected from the Japan Environment and Children’s Study, a large birth cohort...

Librarians at a university had planned to check the collection prior to the library renovations that began in 2015. They had previous knowledge of the presence of a light greyish-white powder with an unpleasant odour (hereinafter referred to as ‘powder’) sprinkled between the pages of antiquarian books in the library archive. The purpose of this st...

The association between daily breakfast habits during pregnancy and offspring neurodevelopment remains unknown. We evaluated the association between breakfast habits during pregnancy and offspring neurodevelopment. Data of 72,260 women with singleton deliveries at and after 37 weeks of gestation enrolled during 2011–2014 in the Japan Environment an...

Background Catch-up growth issues among children born small for gestational age (SGA) present a substantial public health challenge. Prenatal exposure to heavy metals can cause adverse effects on birth weight. However, comprehensive studies on the accurate assessment of individual blood concentrations of heavy metals and their effect on the failure...

Background: Intrauterine exposure to hypertensive disorders of pregnancy (HDP) may increase the risk of neuropsychiatric disorders. This investigation examined for associations between maternal HDP and febrile seizures (FS) in offspring by the age of three years. Methods: The present cohort study analyzed data from the Japan Environment and Chil...

Exposure to low doses of neonicotinoid (NEO) insecticides during pregnancy may have a negative impact on the neurodevelopment of children. Biomarkers are frequently used to investigate the exposure and its health effects in environmental epidemiology. In the present study, we aimed to evaluate the utility of urinary biomarkers of NEO exposure by ca...

Importance Kawasaki disease is an acute systemic vasculitis that primarily affects infants and young children. No reproducible risk factors have yet been identified, but a possible association between maternal folic acid supplementation and Kawasaki disease has been reported previously. Objective To investigate the associations of exposure to mate...

Purpose This investigation assessed the impact of dog and/or cat ownership during infancy on the presence of functional constipation (FC) at 3 years of age. Methods The fixed data of 73,936 singleton births from a large national birth cohort study commencing in 2011 were used to identify FC as estimated by Rome III at 3 years of age. Multiple logi...

Teenage pregnancy increases the threat of depression because of its many factors. Pregnancy during young adulthood may also have several risk factors for depression compared to older pregnancies. However, data on depression in young adult pregnancies are lacking. This study investigated the association between teenage and young adult pregnancy and...

Importance Corticosteroids and β2-adrenergic agonists are commonly used during pregnancy to treat asthma. However, offspring neurodevelopmental outcomes following in utero exposure to these medications remain unclear. Objective To investigate the association between timing of in utero exposure to corticosteroids and β2-adrenergic agonists and offs...

Background: The association between prenatal metal exposure and congenital anomalies is unclear. We aimed to examine the association between exposure to cadmium, lead, mercury, selenium, and manganese and physical abnormalities. Methods: Data from 89,887 pregnant women with singleton pregnancies who participated in the Japan Environment and Chil...

Recently, prediction of gestational diabetes mellitus (GDM) using artificial intelligence (AI) from medical records has been reported. We aimed to evaluate GDM-predictive AI-based models using birth cohort data with a wide range of information and to explore factors contributing to GDM development. This investigation was conducted as a part of the...

To evaluate differences in maternal characteristics and obstetric and offspring childhood outcomes between births at and after 37 weeks of gestation (referred to as term and post-term births) according to the use of tocolytic treatment. Data for 63,409 women with singleton births at and after 37 weeks of gestation were analyzed using data from the...

Importance It is unclear whether increased television (TV) and DVD viewing in early childhood from age 1 year decreases development or whether poor development increases TV/DVD viewing. Objective To investigate the directional association between TV/DVD screen time and performance on developmental screeners in children aged 1 to 3 years. Design,...

This study examined the effects of inserting stretching exercises targeting commonly reported areas of the neck, shoulders, and lower back and short breaks with stretching (1 minute of stretching every 20 minutes) on neck/upper limb movements for endoscopy assistants. Elbow motion distance, head motion distance, and neck flexion angle were measured...

Background The primary objective of this study was to examine risk factors for toddler’s hypertension. Methods Subjects of this study were children and parents participating in a national birth cohort study in Japan, the Japan Environment and Children’s Study. We measured the children’s blood pressure (BP) at 2 and 4 years old. We obtained childre...

Background: Prenatal exposure to metallic elements may adversely affect early childhood health. However, more evidence is needed as population-based cohort studies are currently limited. Objectives: We aimed to examine the associations between prenatal metallic (mercury, selenium, and manganese) exposure and the risk of allergic diseases in early c...

Background: In developed countries, the time fathers spend on childcare has increased steadily in recent decades. However, studies on the relationship between paternal care and child outcomes remain scarce. Thus, we examined the association between paternal involvement in childcare and children's developmental outcomes. Methods: We used Japan's...

Organophosphate (OP) agents are continuously utilized in large amount throughout the globe for crop protection and public health, thereby creating a potential concern on human health. OP agent as an anticholinesterase also acts on the endocannabinoid (EC)-hydrolases, i.e., fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), to rev...

High urinary levels of dialkylphosphates (DAPs), which are common structures of organophosphate pesticides (OPs), have been associated with several adverse health outcomes in human biomonitoring studies. Previous studies have indicated that dietary OP exposure and ingestion of environmentally degraded DAP, which is inactive with acetylcholinesteras...

Objective: To provide an overview of the pathogenesis of pneumatosis cystoides intestinalis (PCI) and hypersensitivity syndrome (HS) caused by trichloroethylene (TCE) and the basic research into their toxicity. Subjects and methods: We reviewed previously published research articles. Results: PCI clustered in Japan in the 1980s is a rare disea...

Later-borns tend to be shorter than first-borns in childhood and adulthood. However, large-scale prospective studies examining growth during infancy according to birth order are limited. We aimed to investigate the relationship between birth order and growth during the first 4 years of life in a Japanese prospective birth cohort study. A total of 2...

The association between maternal pre-pregnancy smoking status and asthma risk is unclear. This study aimed to investigate the association between pre- and post-pregnancy maternal smoking status and bronchial asthma at 3 years of age in a large birth cohort. Data of 75,411 mother–child pairs from the Japan Environment and Children's Study (JECS) wer...

Birth cohort studies examining pregnancy and infant outcomes among adolescent and young adult (AYA) cancer survivors have been limited. The present study examined whether AYA cancer affects pregnancy outcomes of survivors and infectious diseases in their infants up to 1 year of age. Pregnant women were recruited for the Japan Environment and Childr...

Background: The current study aimed to assess the association between low maternal protein intake during pregnancy and child developmental delay at age 3 years. Methods: This research used data obtained from the Japan Environment and Children's Study. In total, we analyzed 77,237 mother-child pairs. Dietary intake was assessed using the Food Fre...

Although endotoxin concentration in the environment is negatively associated with atopic dermatitis (AD) onset in early childhood, the association between endotoxin concentration in the environment and eczema resolution in children with preexisting eczema is unclear. The aim of this study was to evaluate the association between endotoxin concentrat...

This study evaluated the association between labour duration (LD) and incidence of low neonatal Apgar scores and foetal acidosis. Data of 37,682 women with full-term singleton spontaneous vaginal deliveries from the Japan Environment and Children’s Study were analysed. Women were classified according to the median LD as nulliparous (< 10 or ≥ 10 h)...

Phthalate exposure monitoring and risk assessment in non-toilet-trained children are rarely reported. This adjunct study of the Japan Environment and Children's Study assessed cumulative health risks in 1.5-year-old toddlers in the Aichi regional subcohort by biomonitoring 16 urinary metabolites of eight phthalate plasticizers. Overnight urine was...

Background In reproductive medicine, vitamin D (VitD) is of particular interest because its deficiency has been linked to various infertility issues. Thus, preconception care, including appropriate VitD supplementation, is essential, especially in women using assisted reproductive technology (ART). Despite the therapeutic benefits of VitD, adverse...

Background Extra energy intake is commonly recommended for pregnant women to support fetal growth. However, relevant data regarding variations in energy intake and expenditure, body mass index and gestational weight gain (GWG) are frequently not considered. This study aimed to investigate how energy intake during pregnancy and gestational weight ga...

Background: To our knowledge, the association of maternal exposure to metallic elements with weight trajectory pattern from the neonatal period has not been investigated. Objectives: The goals of this study were to identify infant growth trajectories in weight in the first 3 y of life and to determine the associations of maternal blood levels of...

Evidence regarding the long-term risk of infections in preterm infants is lacking. In this study, we examined whether preterm infants developed various common childhood infections more frequently than full-term infants by the age of 2 years by analyzing data from a questionnaire completed by 67,282 mother–toddler pairs in a nationwide birth cohort...

The Parenting Stress Index-Short Form (PSI-SF) has been widely employed to assess parenting stress in a number of research and clinical trials. To date, no parenting stress studies in Japan have examined the factor structure, validity, and reliability of the PSI-SF. Therefore, this study aimed to evaluate the psychometric properties of this 19-item...

Occupational exposure to trichloroethylene (TCE) causes a systemic skin disorder with hepatitis known as TCE hypersensitivity syndrome (TCE-HS). Human Leukocyte Antigen (HLA)-B*13:01 is its susceptibility factor; however, the immunological pathogenesis of TCE-HS remains unknown. We herein examined the hypothesis that autoantibodies to CYP2E1 are pr...

Objectives: Endoscopists often suffer from musculoskeletal disorders due to posture-specific workloads imposed by precise maneuvering or long procedural duration. An ergonomic motion tracking system for endoscopy suite (EMTES) was developed using Azure Kinect sensors to evaluate the occlusion, accuracy, and precision, focusing mainly on upper and...

Compared with the relatively well-investigated effects of childhood exposure to lead on neurocognitive deficits, those of prenatal exposure remain relatively inconclusive. We aimed to investigate the association between prenatal blood lead levels and neurodevelopmental delay during the first three years of life. From a prospective cohort of the Jap...

Urinary cotinine concentration (UCC) reflects smoking status. However, in pregnant women, its association with adverse birth outcomes related to fetal growth is not widely known. Thus, we aimed to explore this relationship by focusing on dose–response relationships. We investigated 86,638 pregnant women enrolled between 2011 and 2014 in a prospecti...

The composition of human gut microbiota influences human health and disease over the long term. Since the flora in specimens can easily change at ambient temperature outside the body, epidemiological studies need feasible methods of stool specimen collection and storage to be established. We aimed to validate two methods: feces frozen-stored in tub...

Background Our recent observational study showed that regular consumption of cow’s milk (CM) formula during early infancy (3–6 months old) was associated with a reduced risk of CM allergy (CMA) at 12 months old. However, the long-term association is unclear. The present study was aimed to examine how long this inverse association persists after 12...

Background Using cohort data from the Japan Environment and Children’s Study (JECS), we previously reported that the risk of sleep deprivation in 1-year-old children was reduced with a higher maternal intake of fermented foods, particularly miso. The present study, which evaluates children from the same cohort at 3 years of age, is a continuation o...

Neurodevelopmental delay is associated with neurodevelopmental disorders. Prenatal metal exposure can potentially cause neurodevelopmental delays in children. This study examines whether prenatal exposure to mercury (Hg) and selenium (Se) is associated with the risk of neurodevelopmental delays in children up to 4 years of age. Children enrolled in...

Introduction The ratio of placental weight to birthweight (PW/BW ratio) is well known as a simple indicator of the prenatal intrauterine environment and placental functioning. We assessed the impact of PW/BW ratio on the risk of neurodevelopmental delay in 3-year-olds. Methods We used data of 71 205 mother–child pairs enrolled in the Japan Environ...

Objectives Infants born small for gestational age (SGA) with no catch-up growth (No-CU) are at high risk of intellectual and developmental disabilities. However, factors leading to No-CU among SGA infants are unclear. This study aimed to examine the association between maternal total cholesterol (TC) in mid-pregnancy and No-CU at 3 years among full...

This study aimed to evaluate the association of neonatal transfer with the risk of neurodevelopmental outcomes at 3 years of age. Data were obtained from the Japan Environment and Children’s Study. A general population of 103,060 pregnancies with 104,062 fetuses was enrolled in the study in 15 Regional Centers between January 2011 and March 2014. L...

Cadmium is a heavy metal that can be found in soil, air, food, and water. Cadmium has toxic effects on the kidneys, bones, and respiratory system. Prenatal exposure to cadmium has been found to affect the mental development of children, but inconsistent results have been found in different studies. Therefore, it is unknown that prenatal cadmium exp...

Background: Pyrethroid (PYR) insecticides are widely used for controlling various pests. There are two types that differ in terms of usage: agricultural-purpose PYR (agriculture-PYR) and hygiene purpose PYR (hygiene-PYRs). Few studies exist on the exposure to these chemicals in small children. In this study, we conducted biomonitoring of urinary p...

There are a limited number of studies in which the depression status was followed up throughout pregnancy and postpartum to 1 year after delivery though 8.6-33% of women with recurrent pregnancy loss (RPL) and 10-25% of women who undergo in vitro fertilization and embryo transfer (IVF-ET) suffer from depression. We examined whether RPL and IVF-ET a...

Background Longitudinal adverse effects of neglect-related behaviors during postpartum, especially repeated maternal non-responsiveness to the crying baby on their neuropsychological developmental trajectory, have not been fully clarified. Objective This study aimed to examine the association between postpartum maternal neglect-related behaviors a...

Background Over the past two decades, domestic shipments of glyphosate (Gly), in the form of an ionic salt, have been increasing steadily in Japan. This increase has raising concerns about the effects of chemical exposure on children. The International Agency for Research on Cancer classified Gly as a “probably carcinogenic to humans (Group 2A)” in...

Background Growth restriction in the prenatal period is a significant public health concern. Metals can negatively affect birth size, and pregnant women may be exposed to metal mixtures. Comprehensive studies analyzing the effects of combined metal exposure with accurate individual blood metal concentrations are limited. The current study investiga...

Background We hypothesized that maternal lifestyle factors, such as physical activity and sleep habits, may be associated with autism spectrum disorder (ASD) in infants. This study aimed to investigate the association between maternal physical activity and sleep before and during pregnancy with infant ASD diagnosed by the age of 3 years. Methods W...

Background Exposure to several metallic elements has been suggested as a risk factor for gestational diabetes mellitus (GDM), but inconsistent findings have been reported. This study aimed to examine the association between the maternal whole blood concentration of metallic elements (Hg, Pb, Cd, Mn, and Se) and GDM using the dataset of the Japan En...

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. Method...

Background: The Japan Environment and Children's Study (JECS) is a nationwide birth cohort study of environmental factors affecting children's health and development. We summarize the complete blood count and chemistry panel statistical data from pregnant women enrolled in JECS. Methods: Statistical data of up to 58,056 mother's sample in their...

Background Manganese (Mn) is an essential trace metal and a neurotoxicant. Adverse effects of Mn exposure on the neurodevelopment of children have been reported. However, there is limited information on the effects of maternal exposure during pregnancy. Objectives We aimed to investigate the association between maternal and cord blood Mn levels an...