Parental occupational exposure to anticancer drugs and radiation: Risk of fetal loss and physical abnormalities in The Japan Environment and Children's Study.

Background: Many studies have indicated an association between maternal occupational exposure to hazardous agents, such as anticancer drugs and ionizing radiation, and an increased risk of adverse pregnancy outcomes, including stillbirths or miscarriages and physical abnormalities in offspring. However, the effects of recent advancements in protective measures to reduce these risks have not been clarified. Aim To investigate the current impact of parental occupational exposure to anticancer drugs and ionizing radiation on stillbirths or miscarriages as well as physical abnormalities under the circumstances of the developed safety protocols.

Infants' early recovery from sleep disturbance is associated with a lower risk of developmental delay in the Japan Environment and Children's Study.

To examine whether patterns, such as the timings of onset or recovery from sleep disturbance, are associated with later developmental problems, including autism spectrum disorder (ASD). Mothers participating in the Japan Environment and Children's Study with a child aged 3 years were included in the analyses. Children were assessed for short sleep and frequent awakenings at 1 month, 6 months, and 1 year of age.

Association of placental weight at birth with maternal whole blood concentration of heavy metals (cadmium, lead, mercury, selenium, and manganese): The Japan Environment and Children's Study (JECS).

Background: Lifelong health is dependent on prenatal growth and development, influenced by the placental intrauterine environment. Charged with dual functions--exchange of oxygen and nutrients as well as a barrier against toxins--the placenta itself is susceptible to environmental exposure to heavy metals.

Objective: To examine the use of placenta weight as a biomarker for heavy metal exposure using a large Japanese cohort of pregnant women.

The effect of parental age on child development at 36 months: Insights from the Japan environment and children's study.

Background: The impact of parent-childbearing age on child development at 36 months of age is controversial.

Aims: We used data from a large cohort study with multiple imputation and mediation analyses of variables.

Methods And Procedures: A total of 72,606 parent-child pairs from the Japan Environment and Children's Study were included in the study.

Sex steroid hormones and allergic diseases in children: a pilot birth cohort study in the Japan Environment and Children's Study cohort.

Background: Numerous studies suggest that sex steroids might play a role in sex disparity observed in allergic diseases in adults. However, whether sex hormones influence allergic diseases in children remains unclear. The aim of the present study was to examine the association of sex steroid hormones with allergic disease in Japanese children.

Association between maternal fish consumption during pregnancy and preterm births: the Japan Environment and Children's Study.

Background: Fish are a rich source of essential nutrients that protect against preterm birth. However, as fish can absorb environmental pollutants, their consumption can also increase the risk of preterm birth. This study aimed to assess whether maternal fish consumption during pregnancy is associated with preterm birth in a nationwide large Japanese cohort that consumed relatively high amounts and many types of fish.

Prenatal metal levels and congenital anomalies of the kidney and urinary tract: The Japan Environment and Children's Study.

Background: Prenatal exposure to metal elements has been reported as a potential risk factor for congenital malformation. However, studies on the relationship with congenital anomalies of the kidney and urinary tract (CAKUT) are very scarce.

Methods: Participants of a prospective cohort from the Japan Environment and Children's Study, conducted at 15 research centers, were recruited between January 2011 and March 2014.

Measles antibody seropositivity among children with allergic diseases: A cross-sectional study in the Japan Environment & Children's Pilot Study.

Background: The relationship between allergic individuals and their responsiveness to routine vaccines has rarely been investigated. This study examined whether the seroprevalence of measles antibody differed between children with and without allergic diseases in the general pediatric population.

Methods: The cross-sectional study was performed within a prospective general birth cohort (a pilot study of the Japan Environment & Children's Pilot Study [JECS]) of children aged 8 years.

Female-dominant estrogen production in healthy children before adrenarche.

Objective: Ultra-sensitive hormone assays have detected slight sex differences in blood estradiol (E2) levels in young children before adrenarche. However, the origin of circulating E2 in these individuals remains unknown. This study aimed to clarify how E2 is produced in young girls before adrenarche.

Physical growth and neurodevelopment during the first year of life: a cohort study of the Japan Environment and Children's Study.

Background: The association between a slower physical growth and poorer neurodevelopment has been established in infants born preterm or small for gestational age. However, this association is inconsistent in term-born infants, and detailed investigations in infancy, when intervention is most beneficial for improving outcomes, are lacking. We therefore examined this association separately by sex during the first year of life in term-born infants.

Possible association between early formula and reduced risk of cow's milk allergy: The Japan Environment and Children's Study.

Background: Despite evidence for the protective effects of early regular exposure to peanut and egg proteins against allergies, the optimal timing of cow's milk (CM) protein exposure is unknown.

Objective: We aimed to determine when during the first year of life CM-based formula consumption becomes associated with lower CM allergy (CMA) risk.

Methods: We used the data set of the Japan Environment and Children's Study (JECS), a nationwide birth cohort involving over 100 000 mother-child pairs.

[Japan Environment Health and Children's Study Publications from the University of Occupational and Environmental Health, Japan].

The Japan Environment Health and Children's Study (JECS) is an ongoing cohort study designed to evaluate the impact of various environmental factors on children's health. In this study, more than 100,000 pregnant women were recruited in 15 regional centers throughout Japan. Within the University of Occupational and Environmental Health, the departments of Pediatrics, Obstetrics and Gynecology, Environmental Health, and the School of Health Sciences collaborate with the JECS University of Occupational and Environmental Health Subunit Center in advancing research in this study.

Associations of dog and cat ownership with wheezing and asthma in children: Pilot study of the Japan Environment and children's study.

Objectives: No previous study has used repeated measures data to examine the associations of dog/cat ownership with wheezing and asthma prevalence among children. This prospective study used repeated measurers analysis to determine whether dog/cat ownership in childhood is an independent risk factor for wheezing and asthma, after adjustment for gestational, socio-economical, and demographical confounders confounders, in Japan.

Methods: We conducted a multicenter pilot study of the Japan Environment and Children's Study (JECS) during 2009-2010.

Poly- and perfluoroalkyl substances in maternal serum: Method development and application in Pilot Study of the Japan Environment and Children's Study.

Poly- and perfluoroalkyl substances (PFAS) have been investigated in a number of cohort studies due to concern over their adverse health effects. The aim of this study was to develop a reliable, high throughput and cost-effective analytical method for a broad range of PFAS in human serum. Protein precipitation, automatic solid phase extraction (SPE) pre-treatment and column-switching LC-MS/MS were employed.

Inability of infants to push up in the prone position and subsequent development.

Background: During routine health screening, some infants cannot maintain the prone position with extended arm support at 6 months. Little is known, however, about the development of full-term infants with this developmental deviation. We investigated the developmental course of infants with this characteristic.

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.

Postal contact with participating children and its impact on response rate: Japan Environment and Children's Pilot Study.

Background: Communication with participating children and its effect on participation outcome is one of the most important but untouched issues in birth cohort studies. The purpose of this study was to assess the effect of postal communication with the participating preschool children on the response rate to postal questionnaires.

Methods: One hundred and five mother-preschool child pairs from the Japan Environment and Children's Study (JECS) pilot cohort were included.