Context Maternal cholesterol is important for fetal development. Whether maternal serum total cholesterol (maternal TC) levels in midpregnancy are associated with small (SGA) or large (LGA) for gestational age independent of prepregnancy body mass index (BMI) and weight gain during pregnancy is inconclusive. Objective This work aimed to prospectively investigate the association between maternal TC in midpregnancy and SGA or LGA. Methods The Japan Environment and Children’s Study is a nationwide prospective birth cohort study in Japan. Participants in this study included 37 449 nondiabetic, nonhypertensive mothers with singleton birth at term without congenital abnormalities. Birth weight for gestational age less than the 10th percentile and greater than or equal to the 90th percentile were respectively defined as SGA and LGA by the Japanese neonatal anthropometric charts. Results The mean gestational age at blood sampling was 22.7 ± 4.0 weeks. After adjustment for maternal age, sex of child, parity, weight gain during pregnancy, prepregnancy BMI, smoking, alcohol drinking, blood glucose levels, household income, and study areas, 1-SD decrement of maternal TC was linearly associated with SGA (odds ratio [OR]: 1.20; 95% CI, 1.15-1.25). In contrast, 1-SD increment of maternal TC was linearly associated with LGA (OR: 1.13; 95% CI, 1.09-1.16). Associations did not differ according to prepregnancy BMI and gestational weight gain (P for interaction > .20). Conclusion Maternal TC levels in midpregnancy were associated with SGA or LGA in a Japanese cohort. It may help to predict SGA and LGA. Favorable maternal lipid profiles for fetal development must be explored.

The effects of prenatal exposure to household pesticides on fetal and neonatal growth have not been fully clarified. The present study aims to determine the effects of prenatal exposure to pesticides on neonates’ body size and growth during the first month. This study included 93,718 pairs of pregnant women and their children from the Japan Environment and Children’s Study. Participants completed self-reporting questionnaires during their second or third trimesters on their demographic characteristics and frequency of pesticide use during pregnancy. Child weight, length, and sex were obtained from medical record transcripts. Birth weight and length, as well as weight and length changes over the first month, were estimated using an analysis of covariance. Frequency of exposure to almost all pesticides had no effects on birth weight and length. However, we found small but significant associations (i) between the use of fumigation insecticides and decreased birth weight, and (ii) between frequencies of exposure to pyrethroid pesticides, especially mosquito coils/mats, and suppression of neonatal length growth. Prenatal exposure to household pesticides, especially those containing pyrethroids, might adversely influence fetal and postnatal growth trajectories.

Fructose-1,6-bisphosphatase (FBPase), an enzyme involved in gluconeogenesis, catalyzes the hydrolysis of fructose-1,6-bisphosphate to fructose-6-phosphate and inorganic phosphate. FBPase deficiency is an autosomal recessive inherited disorder, characterized by episodic attacks of hypoglycemia, ketosis, and lactic acidosis during fasting. In general, urinary organic acid analysis using gas chromatography-mass spectrometry (GC/MS) is very useful for the diagnosis of FBPase deficiency, because the appearance of glycerol or glycerol-3-phosphate in the urine is characteristic of this disease. Here, we report a case of FBPase deficiency in a girl with a history of several severe lactic acidosis events, both as a neonate and after the age of 12 months. The patient was identified as a compound heterozygote with two mutations in the FBPase 1 gene: c.841G>A (p.Glu281Lys) and c.960_961insG (p.Ser321fs). The c.841G>A is a newly identified pathogenic mutation. An abnormal level of glycerol-3-phosphate was not detected in the conventional urinary organic acid analysis using GC/MS after solvent extraction. This method, which is a widely used diagnostic standard, could not detect increased levels of glycerol or glycerol-3-phosphate in the patient's urine, which was sampled during the episode. However, glycerol and glycerol-3-phosphate were detected in the same sample, when it was analyzed using GC/MS with the urease pretreatment non-extraction method. Patients with FBPase deficiency have good glycemic control after correct treatment. Therefore, accurate and early diagnosis is essential for a good prognosis. Accordingly, when a patient presents with hypoglycemia and lactic acidosis, it is important to select the appropriate method of urinalysis for organic acids by GC/MS.

Ready-meal consumption is increasing worldwide; however, its impact on human health remains unclear. We aimed to examine the association between processed food and beverage consumption during pregnancy and pregnancy outcomes. Pregnant women were recruited for the Japan Environment and Children’s Study (JECS), a nationwide, large-scale, prospective cohort study. This study included 104,102 registered children (including fetuses or embryos) and collected questionnaire-based data during the first and second/third trimester of pregnancy. Participants’ medical records were transcribed at pregnancy registration, immediately after delivery, and 1 month after delivery. Logistic regression analysis was used to estimate the association between processed food consumption and pregnancy outcomes. The incidence of stillbirth was higher in the group that consumed moderate (1–2 times per week) and high (≥3–7 times per week) amounts of ready-meals (adjusted odds ratio (aOR) = 2.054, 95% confidence interval (CI): 1.442–2.926, q = 0.002; aOR = 2.632, 95% CI: 1.507–4.597, q = 0.007, respectively) or frozen meals (aOR = 2.225, 95% CI: 1.679–2.949, q < 0.001; aOR = 2.170, 95% CI: 1.418–3.322, q = 0.005, respectively) than in the group that rarely consumed such foods. Processed food consumption during pregnancy should be carefully considered.

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 tubes containing guanidine thiocyanate solution for two months after collection (Method B), and feces excreted in diapers and frozen-stored (Method C). Validation was by comparison with a gold standard Method A. Bacterial flora of five adults were sampled and stored by all three methods. Bacterial composition was examined by amplicon sequencing analysis. Bland–Altman analyses showed that Methods B and C might change relative abundances of certain bacterial flora. Thereafter, we analyzed the bacterial flora of 76 toddlers (two age groups) in stools sampled and processed by Method C. The diversity indices of toddlers’ flora were less than those of adults. The relative abundance of some bacteria differed significantly between children aged 1.5 and 3 years. The specimen collection and storage methods validated in this study are worth adopting in large-scale epidemiological studies, especially for small children, provided the limited accuracy for some specific bacteria is understood.