Prenatal alcohol exposure and adverse fetal growth restriction: findings from the Japan Environment and Children's Study.

BACKGROUNDS: Japanese studies on the association between maternal alcohol consumption and fetal growth are few. This study assessed the effect of maternal alcohol consumption on fetal growth. METHODS: This prospective birth cohort included 95,761 participants enrolled between January 2011 and March 2014 in the Japan Environment and Children's Study. Adjusted multiple linear and logistic regression models were used to assess the association between prenatal alcohol consumption and infant birth size. RESULTS: Consumption of a weekly dose of alcohol in the second/third trimester showed a significant negative correlation with standard deviation (SD; Z) scores for body weight, body length, and head circumference at birth, respectively. Consumption of a weekly dose of alcohol during the second/third trimester had a significant positive correlation with incidences of Z-score ≤ -1.5 for birth head circumference. Associations between alcohol consumption in the second/third trimester and Z-score ≤ -1.5 for birth weight or birth length were not significant. Maternal alcohol consumption in the second/third trimester above 5, 20, and 100 g/week affected body weight, body length, and head circumference at birth, respectively. CONCLUSION: Low-to-moderate alcohol consumption during pregnancy might affect fetal growth. Public health policies for pregnant women are needed to stop alcohol consumption during pregnancy. IMPACT: This study examined the association between maternal alcohol consumption and fetal growth restriction in 95,761 pregnant Japanese women using the prospective birth cohort. Maternal alcohol consumption in the second/third trimester more than 5, 20, and 100 g/week might affect fetal growth in body weight, body length, and head circumference, respectively. The findings are relevant and important for educating pregnant women on the adverse health effects that prenatal alcohol consumptions have on infants.

Short-term prediction of preeclampsia using the sFlt-1/PlGF ratio: a subanalysis of pregnant Japanese women from the PROGNOSIS Asia study.

Two prospective multicenter studies demonstrated that a soluble fms-like tyrosine kinase 1 (sFlt-1)/placental growth factor (PlGF) ratio cutoff of ≤38 can rule out preeclampsia within 1 week with a negative predictive value (NPV) of 99.3% (PROGNOSIS) and 98.6% (PROGNOSIS Asia). We report a subanalysis of the Japanese cohort from the PROGNOSIS Asia study. Pregnant women with suspected preeclampsia between gestational weeks 18 + 0 days and 36 + 6 days were enrolled at eight Japanese sites. Primary objectives: Assess the performance of the Elecsys® sFlt-1/PlGF ratio cutoff ≤38 to rule out preeclampsia within 1 week and of the cutoff >38 to rule in preeclampsia within 4 weeks. Key secondary objectives: Prediction of maternal and fetal adverse outcomes (MAOs/FAOs) and their relationship with duration of pregnancy. Of 192 women enrolled, 180 (93.8%)/175 (91.1%) were evaluable for primary/combined endpoint analyses. Overall preeclampsia prevalence was 13.3%. A sFlt-1/PlGF ratio of ≤38 provided an NPV of 100% (95% confidence interval [CI], 97.5-100) for ruling out preeclampsia within 1 week, and a ratio of >38 provided a positive predictive value of 32.4% (95% CI, 18.0-49.8) for ruling in preeclampsia within 4 weeks. The area under the curve for the prediction of preeclampsia/maternal/fetal adverse outcomes within 1 week was 94.2% (95% CI, 89.3-97.8). After adjusting for gestational age and final preeclampsia status, Cox regression indicated a 2.8-fold greater risk of imminent delivery for women with a sFlt-1/PlGF ratio >38 versus ≤38. This subanalysis of Japanese women with suspicion of preeclampsia showed high predictive value for a Elecsys sFlt-1/PlGF ratio cutoff of 38 for short-term prediction of preeclampsia.

Mediating Factors Between Parental Socioeconomic Status and Small for Gestational Age in Infants: Results from the Hokkaido Study on Environment and Children's Health.

OBJECTIVES: Previous studies indicated a significant association between small for gestational age (SGA) in infants and their parents' socioeconomic status (SES). Thus, this study aimed to examine if parental factors, such as maternal smoking, and the pre-pregnancy body mass index (BMI) could mediate the associations between parental SES and SGA. METHODS: The participants of this study were pregnant women who enrolled in an ongoing birth cohort study, the Hokkaido study, during the first trimester of their pregnancies. A total of 14,593 live singleton births were included in the statistical analysis, of which 1011 (6.9%) were SGA. Two structural equation models were employed to evaluate the associations between parental SES, parental characteristics, and SGA. RESULTS: The effect of low SES on SGA was directly mediated by maternal pre-pregnancy BMI, smoking during the third trimester, and alcohol consumption during the first trimester in the first model, which was based the assumption of independent associations between mediating factors. In the second model, which additionally considered the mediating factors from the first model, smoking during pregnancy mediated decline in parental SES, consequently increased SGA. Moreover, an increase in pregnancy smoking status increased the prevalence of lower maternal pre-pregnancy BMI and its effect on SGA. CONCLUSIONS FOR PRACTICE: In this study, we observed the independent mediating effect of maternal pre-pregnancy BMI, smoking, and alcohol consumption during pregnancy on low SES and, consequently, SGA, with the additional mediating pathway of SES to smoking to low BMI on SGA.

Morphofunctional cardiac changes in singleton and twin pregnancies: a longitudinal cohort study.

BACKGROUND: This study aimed to compare the echocardiographic changes and cardiac biomarkers between women with singleton and twin pregnancies. METHODS: From April 2014 to March 2016, this longitudinal cohort study invited pregnant women who were scheduled to give birth at Hokkaido University Hospital. We analyzed prospectively collected data on simultaneously determined echocardiographic parameters and blood cardiac markers of 44 women with singleton and 22 women with twin pregnancies. Furthermore, we tested the mixed-effect models for echocardiographic parameters and cardiac biomarkers. RESULTS: During the third trimester and immediately postpartum (within 1 week after childbirth), the mean left atrial volume index and brain natriuretic peptide (BNP) level were significantly higher in women with twin pregnancies than in those with singleton pregnancies. Women with twin pregnancies also had significantly smaller second-trimester inferior vena cava diameters and significantly higher third-trimester creatinine levels than those with singleton pregnancies. BNP positively correlated with the left atrial volume index (ß = 0.49, p < 0.01) and the ratio of early diastolic transmitral to mitral annular velocity (E/e') (ß = 0.41, p < 0.01). At 1 month after childbirth in women with singleton pregnancies, BNP and N-terminal precursor protein BNP (NT-proBNP) fragments immediately postpartum negatively correlated with the later E/e' (r = - 0.33, p = 0.02 and r = - 0.36, p < 0.01, respectively). CONCLUSIONS: The intravascular cardiac load reached maximum within 1 week after childbirth and was greater in women with twin pregnancies than in those with singleton pregnancies. BNP/NT-proBNP significantly positively correlated with LA volume index and E/e'. In women with singleton pregnancies, BNP secreted immediately after childbirth might improve the diastolic functions 1 month after childbirth.

Placenta-specific epimutation at H19-DMR among common pregnancy complications: its frequency and effect on the expression patterns of H19 and IGF2.

BACKGROUND: H19 and IGF2 genes are imprinted and involved in regulating fetal and placental growth. The H19 differentially methylated region (DMR) is paternally methylated and maternally unmethylated and regulates the imprinted expression of H19 and IGF2. Epimutation at the H19-DMR in humans results in congenital growth disorders, Beckwith-Wiedemann and Silver-Russell syndromes, when erroneously its maternal allele becomes methylated and its paternal allele becomes unmethylated, respectively. Although H19 and IGF2 have been assessed for their involvement in pregnancy complications including fetal growth restriction (FGR) and pregnancy-induced hypertension (PIH)/hypertensive disorder of pregnancy (HDP) intensively in the last decade, it is still not established whether epimutation at the H19-DMR in the placenta results in pathogenic conditions in pregnancy. We aimed to assess the frequency of H19-DMR epimutation and its effects on the allelic expression patterns of H19 and IGF2 genes among normal and abnormal pregnancy cases. RESULTS: We enrolled two independently collected sets of placenta samples from normal pregnancies as controls and common pregnancy complications, FGR and PIH (HDP). The first set consisted of 39 controls and 140 FGR and/or PIH cases, and the second set consisted of 29 controls and 62 cases. For these samples, we initially screened for DNA methylation changes at H19-DMR and IGF2-DMRs by combined bisulfite restriction analysis, and further analyzed cases with methylation changes for their allelic methylation and expression patterns. We identified one case each of FGR and PIH showing hypomethylation of H19-DMR and IGF2-DMRs only in the placenta, but not in cord blood, from the first case/control set. For the PIH case, we were able to determine the allelic expression pattern of H19 to be biallelically expressed and the H19/IGF2 expression ratio to be highly elevated compared to controls. We also identified a PIH case with hypomethylation at H19-DMR and IGF2-DMRs in the placenta from the second case/control set. CONCLUSIONS: Placental epimutation at H19-DMR was observed among common pregnancy complication cases at the frequency of 1.5% (3 out of 202 cases examined), but not in 68 normal pregnancy cases examined. Alteration of H19/IGF2 expression patterns due to hypomethylation of H19-DMR may have been involved in the pathogenesis of pregnancy complications in these cases.

The relationship between prenatal psychological stress and placental abruption in Japan, The Japan Environment and Children's Study (JECS).

BACKGROUND: Prenatal psychological stress may increase the risk of placental abruption (PA). This study aimed to clarify the effects of psychological distress during pregnancy and exposure to stressful life events in the year before or during pregnancy on the occurrence of PA in Japanese women. METHODS: Using a nationwide prospective birth cohort study, we obtained data from 103,099 women between January 2011 and March 2014. Information on exposure to 14 stressful life events and psychological distress (Kessler 6 scale) was collected using a self-administered questionnaire during pregnancy. Clinical diagnoses of PA were obtained from medical records. A total of 80,799 women with singleton births were analyzed using logistic regression models that adjusted for possible confounders. RESULTS: PA was diagnosed in 335 (0.4%) women. There was no significant difference in the Kessler 6 score during pregnancy between the PA group and non-PA group. Exposure to the death of a child in the year before or during pregnancy was significantly associated with PA in multigravid women (adjusted odds ratio [aOR] 3.57; 95% confidence interval [CI] 1.50-8.34). A spouse's loss of employment was significantly associated with PA in parous women (aOR 3.25; 95% CI 1.40-7.56). CONCLUSIONS: This study identified the possible effects of exposure to the death of a child on PA occurrence that adjusted for important confounding factors.

Fetal middle cerebral artery peak systolic velocity as a predictor of fetal anemia in unselected women giving birth at or near term.

OBJECTIVE: This study was performed to evaluate the application of fetal middle cerebral artery peak systolic velocity (MCA-PSV) for prediction of newborn anemia with umbilical cord blood hemoglobin concentration at birth (UCB-Hb) < 10.0 g/dL among infants born at gestational week (GW) ≥ 36 to unselected women. MATERIALS AND METHODS: We reviewed the medical charts of 699 women giving birth to singleton infants at GW ≥ 36 with available data on MCA-PSV measured at GW ≥ 25 at the discretion of the attending physician. Multiple of the median (MoM) MCA-PSV (MCA-PSV MoM) > 1.5 was defined as a positive MCA-PSV test result. RESULTS: The MCA-PSV test was applied 2309 times (313 and 1996 times during second and third trimesters, respectively) in 699 women. The results were positive in 4.4% (102/2309) of tests and at least once in 9.9% (69/699) of women. Anemic infants were born to one (1.4%) and six (1.0%) of 69 and 630 women with and without at least one positive test result, respectively. MoM determined 4, 3, and 2 weeks before birth showed significant weak negative correlations with UCB-Hb at birth (correlation coefficient: 0.298-0.325). CONCLUSIONS: Among unselected women giving birth at or near term, the MCA-PSV test was unsatisfactory for prediction of newborn anemia in this retrospective observational study.

Association Between Maternal Serum Folate Concentrations in the First Trimester and the Risk of Birth Defects: The Hokkaido Study of Environment and Children's Health.

BACKGROUND: Low red blood cell folate concentrations during early pregnancy might cause neural tube defects. However, the association between folate concentrations and birth defects of other neural crest cell-derived organs remains unknown. We investigated the associations between birth defects and first-trimester serum folate concentrations in a birth-cohort study in Japan. METHODS: In total, 14,896 women who were prior to 13 weeks of gestation were enrolled from 2003 through 2012. Birth defect information was obtained from medical records and questionnaires. The association between folate levels in the first trimester and birth defects categorized as ICD-10 cord defects and neural crest cell-derived organ defects was examined. The crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) per log-transformed folate concentration were calculated using logistic regression. RESULTS: Blood samples were obtained at a mean of 10.8 weeks of gestation. Median serum folate level was 16.5 (interquartile range, 13.4-21.5) nmol/L, and the deficiency level (less than 6.8 nmol/L) was 0.7%. There were 358 infants with birth defects. The adjusted odds ratio for any birth defect, ventricular septal defects, and cleft lip was 0.99 (95% CI, 0.74-1.32), 0.63 (95% CI, 0.30-1.33), and 4.10 (95% CI, 0.96-17.58), respectively. There were no significant associations between first-trimester maternal serum folate and the risk of birth defects. CONCLUSIONS: We were unable to demonstrate a relationship between maternal serum folate in the first trimester and birth defects. Potential confounding factors may have influenced our results.

Association of peripartum troponin I levels with left ventricular relaxation in women with hypertensive disorders of pregnancy.

Objective: Women with hypertensive disorders of pregnancy (HDP) show elevated risk of heart failure despite decreased circulating plasma volume compared with those with normotensive control pregnancies (NCP). This study was performed to better characterise the heart in women with HDP and determine whether high-sensitivity troponin I (hs-TnI) around childbirth predicts reduced left ventricular (LV) relaxation at 1 month postpartum. Methods: Echocardiography was performed longitudinally during the first, second and third trimesters and immediately postpartum within 1 week and 1 month postpartum in 24 women with HDP, with simultaneous determination of blood variables in comparison with 51 women with NCP. Results: Compared with NCP, HDP showed greater antepartum left atrial (LA) volume, LV mass and inferior vena cava (IVC) diameter, higher peripartum brain natriuretic peptide/N-terminal pro-B-type natriuretic peptide and hs-TnI with the highest value immediately postpartum, and lower early diastolic mitral annular velocity (e') during pregnancy/postpartum. In analyses of data on HDP and NCP, hs-TnI at the third trimester as well as that immediately postpartum was negatively correlated with later e' at 1 month postpartum. The areas under the receiver operating characteristic curves were 0.82 and 0.81 for hs-TnI at the third trimester and immediately postpartum, respectively, in the prediction of reduced LV relaxation at 1 month postpartum. Conclusion: Reduced LV diastolic function and decreased splanchnic blood reservoir may contribute to the increased third trimester IVC diameter and LA volume in women with HDP. The rise in hs-TnI around childbirth was associated with poor LV relaxation ability at 1 month postpartum.

Morphofunctional cardiac changes in pregnant women: associations with biomarkers.

Objective: This longitudinal study was performed to determine changes in echocardiography parameters in association with various biomarker levels in pregnancy/postpartum. Methods: Fifty-one healthy pregnant women underwent echocardiography with simultaneous determination of blood levels of five biomarkers at each of the first, second and third trimesters of pregnancy, immediately postpartum within 1 week after childbirth and approximately 1 month postpartum. Data on 255 echocardiography scans (five times per woman) and biomarkers were analysed. Results: Left ventricular end-diastolic dimension, left atrial (LA) volume index and left ventricular (LV) mass index increased with advancing gestation and reached the maximum immediately postpartum concomitant with the highest brain natriuretic peptide (BNP), N-terminal pro B-type natriuretic peptide (NT-proBNP), high-sensitivity troponin I (hs-TnI) and creatine kinase MB levels. The inferior vena cava diameter was significantly reduced in the third trimester compared with that in the first trimester and the peak occurred immediately after childbirth. In 255 paired measurements, hs-TnI level was significantly positively correlated with LA volume index and LV mass index; BNP and NT-proBNP were significantly positively correlated with LA volume index and estimated glomerular filtration rate (eGFR) was significantly positively correlated with the average of early diastolic septal and lateral mitral annular velocity (e'). Conclusions: Maximal cardiac changes in morphology occurred postpartum within 1 week after childbirth, not during pregnancy. BNP/NT-proBNP, hs-TnI and eGFR reflected cardiac changes in pregnancy.