Maternal vegetable intake in early pregnancy and wheeze in offspring at the age of 2 years

BACKGROUND/OBJECTIVES

Vegetable intake during childhood may reduce the risk of subsequent asthma. We verified the effect of maternal intake during pregnancy on asthma risk in offspring, which has rarely been studied.

SUBJECTS/METHODS

In a hospital-based birth cohort study conducted in Tokyo, we administered a food frequency questionnaire at two periods during the respondents' pregnancy: early and mid to late periods. In addition, a questionnaire including the International Study of Asthma and Allergies in Childhood questionnaire was conducted when the offspring were 2 years old. Multivariate Poisson regression adjusting for maternal baseline demographics was used to elucidate the association between maternal vegetable intake and the incidence of wheeze in the offspring.

RESULTS

Among 310 singletons, 82 (26.5%) experienced wheeze at 2 years of age. Women with the highest intake of cruciferous, and folate-rich vegetables during early pregnancy reported a significantly lower prevalence of wheeze in their child at 2 years of age in comparison with those who reported the lowest intake (adjusted risk ratio: 0.48 and 0.47, 95% confidence interval: 0.26-0.89, and 0.25-0.87, respectively). In trend analysis, a higher maternal intake of cruciferous, folate-rich vegetables, and total vegetables during early pregnancy was less likely to be associated with wheeze in the offspring at 2 years old (p for trend: 0.038, <0.001, and 0.028, respectively). Maternal vegetable intake during mid to late pregnancy was not associated with wheeze in the offspring.

CONCLUSIONS

Maternal vegetable intake during early pregnancy may have a protective effect against asthma in offspring at 2 years of age.

Comprehensive Assessment of Risk Factors of Cause-Specific Infant Deaths in Japan

Background

Public attention is given to infants with socially high risks of child abuse and neglect, while clinical attention is provided to infants with a biologically high risk of diseases. However, few studies have systematically evaluated how biological or social factors cross over and affect cause-specific infant mortality.

Methods

We linked birth data with death data from the Japanese national vital statistics database for all infants born from 2003–2010. Using multivariate logistic regression, we examined the association between biological and social factors and infant mortality due to medical causes (internal causes), abuse (intentional external causes), and accidents (unintentional external causes).

Results

Of 8,941,501 births, 23,400 (0.26%) infants died by 1 year of age, with 21,884 (93.5%) due to internal causes, 175 (0.75%) due to intentional external causes, and 1,194 (5.1%) due to unintentional external causes. Infants with high social risk (teenage mothers, non-Japanese mothers, single mothers, unemployed household, four or more children in the household, or birth outside of health care facility) had higher risk of death by intentional, unintentional, and internal causes. Infant born with small for gestational age and preterm had higher risks of deaths by internal and unintentional causes, but not by intentional causes.

Conclusions

Both biological as well as social factors were associated with infant deaths due to internal and external causes. Interdisciplinary support from both public health and clinical-care professionals is needed for infants with high social or biological risk to prevent disease and injury.

Dose-response relationship between weight status and clinical outcomes in pediatric influenza-related respiratory infections

BACKGROUND

Associations between underweight/obesity and manifestations of influenza infection remain unclear, especially in children. This study investigated the dose-response relationships between weight status and clinical outcomes among children hospitalized with influenza-related respiratory infections.

METHODS

We obtained hospital discharge records of inpatients aged under 18 years with diagnoses of bronchitis/pneumonia and influenza, using a Japanese national inpatient database. The patients were classified as underweight, normal-weight, overweight, or obese groups using weight-for-length, weight-for-height, and body-mass-index for age following World Health Organization criteria. We compared need for intensive care, 30-day readmission, mean total hospitalization costs, and length of hospital stay across the four groups using multivariable regression models and restricted cubic spline functions.

RESULTS

Overall, 27 771 patients were identified, including 2637 underweight, 19 701 normal-weight, 2675 overweight, and 2758 obese patients. The underweight group showed a significantly higher 30-day readmission (adjusted odds ratio, 1.68; 95% confidence interval, 1.28-2.18) and a longer length of stay (adjusted difference, 0.23 days; 95% confidence interval, 0.12-0.23 days) than the normal-weight group did. No significant differences in the need for intensive care or hospitalization costs were observed across the four weight status groups. The threshold for a statistically significant association between weight status and 30-day readmission was a z-score for weight-for-length, weight-for-height, or BMI for age of -0.95 (17th percentile).

CONCLUSION

These findings demonstrated that underweight status is a risk factor for repeated hospital admissions because of influenza-related respiratory infections in children.

Variations in Oxygen Saturation Targeting, and Retinopathy of Prematurity Screening and Treatment Criteria in Neonatal Intensive Care Units: An International Survey

BACKGROUND

Rates of retinopathy of prematurity (ROP) and ROP treatment vary between neonatal intensive care units (NICUs). Neonatal care practices, including oxygen saturation (SpO2) targets and criteria for the screening and treatment of ROP, are potential contributing factors to the variations.

OBJECTIVES

To survey variations in SpO2 targets in 2015 (and whether there had been recent changes) and criteria for ROP screening and treatment across the networks of the International Network for Evaluating Outcomes in Neonates (iNeo).

METHODS

Online prepiloted questionnaires on treatment practices for preterm infants were sent to the directors of 390 NICUs in 10 collaborating iNeo networks. Nine questions were asked and the results were summarized and compared.

RESULTS

Overall, 329/390 (84%) NICUs responded, and a majority (60%) recently made changes in upper and lower SpO2 target limits, with the median set higher than previously by 2-3% in 8 of 10 networks. After the changes, fewer NICUs (15 vs. 28%) set an upper SpO2 target limit > 95% and fewer (3 vs. 5%) a lower limit < 85%. There were variations in ROP screening criteria, and only in the Swedish network did all NICUs follow a single guideline. The initial retinal examination was carried out by an ophthalmologist in all but 6 NICUs, and retinal photography was used in 20% but most commonly as an adjunct to indirect ophthalmoscopy.

CONCLUSIONS

There is considerable variation in SpO2 targets and ROP screening and treatment criteria, both within networks and between countries.

Respiratory Management of Extremely Preterm Infants: An International Survey

BACKGROUND

There are significant international variations in chronic lung disease rates among very preterm infants yet there is little data on international variations in respiratory strategies.

OBJECTIVE

To evaluate practice variations in the respiratory management of extremely preterm infants born at < 29 weeks' gestational age (GA) among 10 neonatal networks participating in the International Network for Evaluating Outcomes (iNeo) of Neonates collaboration.

METHODS

A web-based survey was sent to the representatives of 390 neonatal intensive care units from Australia/New Zealand, Canada, Finland, Illinois (USA), Israel, Japan, Spain, Sweden, Switzerland, and Tuscany (Italy). Responses were based on practices in 2015.

RESULTS

Overall, 321 of the 390 units responded (82%). The majority of units within networks (40-92%) mechanically ventilate infants born at 23-24 weeks' GA on continuous positive airway pressure (CPAP) with 30-39% oxygen in respiratory distress within 48 h after birth, but the proportion of units that offer mechanical ventilation for infants born at 25-26 weeks' GA at similar settings varied significantly (20-85% of units within networks). The most common respiratory strategy for infants born at 27-28 weeks' GA on CPAP with 30-39% oxygen with respiratory distress within 48 h after birth used by units also varied significantly among networks: mechanical ventilation (0-60%), CPAP (3-82%), intubation and surfactant administration with immediate extubation (0-75%), and less invasive surfactant administration (0-68%).

CONCLUSIONS

There are marked variations but also similarities in respiratory management of extremely preterm infants between networks. Further collaboration and exploration is needed to better understand the association of these variations in practice with pulmonary outcomes.

Impact of pediatric obesity on acute asthma exacerbation in Japan

BACKGROUND

Asthma and obesity are common health problems in children. This study investigated the impact of obesity on children hospitalized with acute asthma exacerbation.

METHODS

We obtained the hospital discharge records of inpatients aged 3-8 years with a diagnosis of asthma using a national inpatient database in Japan. The patients were classified into underweight, normal weight, overweight, and obese groups using weight for height and body mass index for age provided by the World Health Organization. We compared 30-day re-admission, need for intensive care, mean total hospitalization costs, and length of hospital stay between the 4 groups using multivariable regression models.

RESULTS

Overall, 38 679 patients were identified, including 3177 underweight, 28 904 normal weight, 3334 overweight, and 3264 obese patients. The obese group showed significantly higher 30-day re-admission (adjusted odds ratio, 1.26; 95% confidence interval, 1.03-1.54) and longer length of stay (adjusted difference, 0.12 days; 95% confidence interval, 0.10-0.20 days) than the normal weight group. The threshold was a 91st percentile of weight for length or body mass index for the relationship with 30-day re-admission. No significant difference was observed between the 4 groups regarding the need for intensive care and total hospitalization costs.

CONCLUSION

These findings demonstrated that obesity was a risk factor for repeated admissions caused by asthma in children, indicating the importance for the prevention of pediatric obesity.

Survival in Very Preterm Infants: An International Comparison of 10 National Neonatal Networks

OBJECTIVES

To compare survival rates and age at death among very preterm infants in 10 national and regional neonatal networks.

METHODS

A cohort study of very preterm infants, born between 24 and 29 weeks' gestation and weighing <1500 g, admitted to participating neonatal units between 2007 and 2013 in the International Network for Evaluating Outcomes of Neonates. Survival was compared by using standardized ratios (SRs) comparing survival in each network to the survival estimate of the whole population.

RESULTS

Network populations differed with respect to rates of cesarean birth, exposure to antenatal steroids and birth in nontertiary hospitals. Network SRs for survival were highest in Japan (SR: 1.10; 99% confidence interval: 1.08-1.13) and lowest in Spain (SR: 0.88; 99% confidence interval: 0.85-0.90). The overall survival differed from 78% to 93% among networks, the difference being highest at 24 weeks' gestation (range 35%-84%). Survival rates increased and differences between networks diminished with increasing gestational age (GA) (range 92%-98% at 29 weeks' gestation); yet, relative differences in survival followed a similar pattern at all GAs. The median age at death varied from 4 days to 13 days across networks.

CONCLUSIONS

The network ranking of survival rates for very preterm infants remained largely unchanged as GA increased; however, survival rates showed marked variations at lower GAs. The median age at death also varied among networks. These findings warrant further assessment of the representativeness of the study populations, organization of perinatal services, national guidelines, philosophy of care at extreme GAs, and resources used for decision-making.

Association between very advanced maternal age and adverse pregnancy outcomes: a cross sectional Japanese study

Background

While several studies have demonstrated the increased risk of pregnancy complications for women of advanced age, few studies have focused on women with very advanced age (≥ 45), despite the increasing rate of pregnancy among such women. Furthermore, how such risks of increase in age differ by maternal characteristics are also poorly understood. Thus, we aimed to clarify pregnant outcomes among women with very advanced age and how the effect of age differs by method of conception and parity.

Methods

We used the national multicenter Japan Society of Obstetrics and Gynecology perinatal database, including 365,417 women aged 30 years or older who delivered a singleton between 2005 and 2011. We divided women into four groups based on age (years): 30–34, 35–39, 40–44, and ≥45, and compared risk of adverse birth outcomes between the groups using Poisson regression. Effect modification by parity and use of assisted reproductive technology (ART) was also evaluated.

Results: Compared with women aged 30–34 years, women aged 45 or older had higher risk of emergency cesarean delivery [adjusted risk ratio (aRR): 1.77, 95% confidence interval (95% CI): 1.58–1.99], preeclampsia (aRR: 1.86, 95% CI: 1.43–2.42), severe preeclampsia (aRR: 2.03, 95% CI: 1.31–3.13), placenta previa (aRR: 2.17, 95% CI: 1.60–2.95), and preterm birth (aRR: 1.20, 95% CI: 1.04–1.39). The effect of older age on risk of emergency cesarean section, preeclampsia, and preterm birth were significantly greater among those who conceived naturally compared to those who conceived by ART. The effect on emergency cesarean section was stronger among primiparous women, whereas the risk of preeclampsia associated with older age was significantly greater among multiparous women.

Conclusions

Very advanced maternal age (≥ 45) was related to greater risk for adverse birth outcomes compared to younger women, especially for maternal complications including cesarean section, preeclampsia, severe preeclampsia, and placenta previa. The magnitude of the influence of age also differed by conception method and by parity.

Ecological analysis of secular trends in low birth weight births and adult height in Japan

BACKGROUND

Japan, which currently maintains the highest life expectancy in the world and has experienced an impressive gain in adult height over the past century, has suffered a dramatic twofold increase in low birth weight (LBW) births since the 1970s.

METHODS

We observed secular trends in birth characteristics using 64 115 249 live births included the vital statistics (1969-2014), as well as trends in average height among 3 145 521 adults born between 1969 and 1996, included in 79 surveys conducted among a national, subnational or community population in Japan.

RESULTS

LBW rates exhibited a U-shaped pattern showing reductions until 1978-1979 (5.5%), after which it increased. Conversely, average adult height peaked for those born during the same period (men, 171.5 cm; women, 158.5 cm), followed by a reduction over the next 20 years. LBW rate and adult height showed a strong inverse correlation (men, r=-0.98; women, r=-0.88). A prediction model based on birth and economical characteristics estimated the national average of adult height would continue to decline, to 170.0cm (95% CI 169.6 to 170.3) for men and 157.9cm (95% CI 157.5 to 158.3) for women among those born in 2014.

CONCLUSIONS

Adult height in Japan has started to decline for those born after 1980, a trend that may be attributed to increases in LBW births over time. Considering the known association between shorter adult height and adverse health outcomes, evidence of population-level decline in adult health due to long-term consequences of increasing LBW births in Japan is anticipated.

Inter-prefecture disparity in under-5 mortality: 115 year trend in Japan

BACKGROUND

Child poverty is a growing, serious issue in Japan, where various social disparities are increasing. Numerous reports have focused on the relationship between social inequity and health, but few studies have assessed how the overall magnitude of disparities in child health has changed in the course of drastic social and economic transitions from 1899 to more recent times. In this study, we assessed the trend of the under-5 mortality rate (U5MR) and its inter-prefecture disparity in Japan.

METHODS

This is a secondary analysis of Japan's vital statistics data from 1899 to 2014 (115 years), which covers a core period of modern Japan. We calculated the U5MR of each prefecture and its Theil index by year to assess the trend of inter-prefecture disparity in child health from 1899 to 2014.

RESULTS

The U5MR monotonically decreased from 238 per 1,000 births in 1899 to 3 in 2014. The Theil index of the U5MR increased in the post-war period, peaked in 1962 (0.027) and gradually reduced to <0.01 in the 1970s. In the 2000s, however, even though U5MR continued to decrease, the Theil index started to increase, and in 2014 (0.013) it exceeded that in 1970 and was more similar to that before World War II.

CONCLUSIONS

The disparities in child health appear to be widening, and may serve as a warning to today's society that increasing socioeconomic gradients may lead to rising health inequity among children. Further investigations into the causes, mechanisms, and possible interventions are needed.

Increases in Caesarean Delivery Rates and Change of Perinatal Outcomes in Low- and Middle-Income Countries: A Hospital-Level Analysis of Two WHO Surveys

BACKGROUND

Maternal and neonatal outcomes have improved substantially. During the same period, the caesarean delivery rate soared. The aim of this analysis was to determine whether an increase in caesarean rate was associated with an improvement in perinatal outcome at an institutional level in low- and middle-income countries.

METHODS

The WHO Global Survey on Maternal and Perinatal Health (WHOGS) and the WHO Multi-Country Survey on Maternal and Newborn Health (WHOMCS) were two multi-country, facility-based, cross-sectional surveys conducted in 2004-08 and 2010-11, respectively. The increase in caesarean rate and the change of prevalence of adverse perinatal outcomes were calculated using a two-point estimator of percent change annualized (PCA) method. Maternal, perinatal, and neonatal composite indexes were used as the outcomes. A linear mixed model was used to assess the association between the change of caesarean rate and the change of perinatal outcome.

RESULTS

A total of 259 facilities in 20 countries participated in both surveys, with 217 844 women in WHOGS and 227 734 women in WHOMCS. The caesarean rate in these facilities increased, on average, by 4.0% annually, while the prevalence of adverse perinatal outcomes decreased by 4.6% annually. However, after adjustments for potential confounders, no association was found between the increase in caesarean rate and the change of adverse outcome indexes, regardless of whether starting caesarean rates were already high (above 10%) or not.

CONCLUSIONS

In low- and middle-income countries, the increases in caesarean rates were not associated with improved perinatal outcomes regardless of whether the starting caesarean rate was already high or not.

Preeclampsia mediates the association between shorter height and increased risk of preterm delivery

Background

Maternal short stature has been observed to increase the risk of preterm birth; however, the aetiology behind this phenomenon is unknown. We investigated whether preeclampsia, an obstetric complication that often leads to preterm delivery and is reported to have an inverse association with women’s height, mediates this association.

Methods

We studied 218 412 women with no underlying diseases before pregnancy, who delivered singletons from 2005 to 2011 and were included in the Japan Society of Obstetrics and Gynecology perinatal database, which is a national multi-centre-based delivery database among tertiary hospitals. We assessed the risk of preterm delivery in relation to height using multivariate analysis, and how the association was mediated by risk of preeclampsia using mediation analysis.

Results

Each 5-cm decrement in height was associated with significantly higher risk of preterm delivery [relative risk 1.20; 95% confidence interval (CI): 1.13, 1.27] and shorter gestational age (−0.30; 95% CI: −0.44, −0.16 weeks). Mediation analysis showed that the effect of shorter height on increased risk of preterm delivery, due to an indirect effect mediated through increased risk of preeclampsia, was substantial for shorter gestational age (48%), as well as risk of preterm delivery (28%). When examining the three subtypes of preterm delivery separately, mediated effect was largest for provider-initiated preterm delivery without premature rupture of membranes (PROM) (34%), compared with spontaneous preterm delivery without PROM (17%) or preterm delivery with PROM (0%).

Conclusions

Preeclampsia partially mediates the association between maternal short stature and preterm delivery.

Pre-pregnancy BMI-specific optimal gestational weight gain for women in Japan

Background

The Institute of Medicine (IOM) guidelines are the most widely used guidelines on gestational weight gain; however, accumulation of evidence that body composition in Asians differs from other races has brought concern regarding whether their direct application is appropriate. We aimed to study to what extent optimal gestational weight gain among women in Japan differs by pre-pregnancy body mass index (BMI) and to compare estimated optimal gestational weight gain to current Japanese and Institute of Medicine (IOM) recommendations.

Methods

We retrospectively studied 104,070 singleton pregnancies among nulliparous women in 2005–2011 using the Japanese national perinatal network database. In five pre-pregnancy BMI sub-groups (17.0–18.4, 18.5–19.9, 20–22.9, 23–24.9, and 25–27.4 kg/m²), we estimated the association of the rate of gestational weight gain with pregnancy outcomes (fetal growth, preterm delivery, and delivery complications) using multivariate regression.

Results

Weight gain rate associated with the lowest risk of adverse outcomes decreased with increasing BMI (12.2 kg, 10.9 kg, 9.9 kg, 7.7 kg, and 4.3 kg/40 weeks) for the five BMI categories as described above, respectively. Current Japanese guidelines were lower than optimal gains, with the lowest risk of adverse outcomes for women with BMI below 18.5 kg/m², and current IOM recommendations were higher than optimal gains for women with BMI over 23 kg/m².

Conclusion

Optimal weight gain during pregnancy varies largely by pre-pregnancy BMI, and defining those with BMI over 23 kg/m² as overweight, as proposed by the World Health Organization, may be useful when applying current IOM recommendations to Japanese guidelines.

•

We estimated gestational weight gain that optimizes pregnancy outcomes in Japanese.

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Optimal gain was 12.2 kg/40 weeks for pre-pregnancy BMI 17.0–18.4 kg/m².

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Optimal gain was 4.3 kg/40 weeks for pre-pregnancy BMI 25.0–27.4 kg/m².

•

Current national guidelines are too low for women with pre-pregnancy BMI < 18.5 kg/m².

•

BMI > 23 kg/m² should be defined as overweight if applying IOM recommendations.

Diagnostic Accuracy of Ultrasound Scanning for Prenatal Microcephaly in the context of Zika Virus Infection: A Systematic Review and Meta-analysis

To assess the accuracy of ultrasound measurements of fetal biometric parameters for prenatal diagnosis of microcephaly in the context of Zika virus (ZIKV) infection, we searched bibliographic databases for studies published until March 3rd, 2016. We extracted the numbers of true positives, false positives, true negatives, and false negatives and performed a meta-analysis to estimate group sensitivity and specificity. Predictive values for ZIKV-infected pregnancies were extrapolated from those obtained for pregnancies unrelated to ZIKV. Of 111 eligible full texts, nine studies met our inclusion criteria. Pooled estimates from two studies showed that at 3, 4 and 5 standard deviations (SDs) Collapse

Key Words Collapse

MESH Headings

• Fetal Diseases/diagnostic imaging
• Fetal Diseases/virology
• Humans
• Microcephaly/diagnostic imaging
• Microcephaly/embryology
• Microcephaly/virology
• Reproducibility of Results
• Sensitivity and Specificity
• Ultrasonography, Prenatal/methods
• Zika Virus/isolation & purification
• Zika Virus/physiology
• Zika Virus Infection/diagnostic imaging
• Zika Virus Infection/embryology
• Zika Virus Infection/virology

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Grants

• 001 World Health Organization

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Provider-initiated delivery, late preterm birth and perinatal mortality: a secondary analysis of the WHO multicountry survey on maternal and newborn health

Introduction

In high-income countries, a reduced clinical threshold for obstetric interventions such as labour induction (LI) and prelabour caesarean delivery (PLCD) has played a substantial role in increasing rates of late preterm births. However, the association between provider-initiated delivery and perinatal outcomes have not been studied in a multicountry setting including low-income and middle-income countries.

Methods

286 hospitals in 29 countries participated in the WHO Multi-Country Survey on Maternal and Newborn Health and yielded 2 52 198 singleton births of at least 34 weeks in 2010–2011. We used an ecological analysis based on generalised estimating equations under multilevel logistic regression to estimate associations between hospital rates of PLCD and LI with rates of late preterm birth (34–36 weeks), stillbirth and intrahospital early neonatal death, in relation to country development based on the Human Development Index (HDI).

Results

Rates of LI were higher in hospitals from very high-HDI (median 10.9%) and high-HDI (11.2%) countries compared with medium-HDI (4.0%) or low-HDI (3.8%) countries. Rates of PLCD were by far the lowest in low-HDI countries compared with countries in the other three categories (5.1% vs 12.0%–17.9%). Higher rates of PLCD were associated with lower perinatal death rates (OR 0.87 (0.79, 0.95) per 5% increase in PLCD) and non-significantly with late preterm birth (1.04 (0.98, 1.10)) regardless of country development. LI rates were positively associated with late preterm birth (1.04 (1.01, 1.06)) regardless of country development and with perinatal death (1.06 (0.98, 1.15)) only in middle-HDI and low- HDI countries.

Conclusion

PLCD was associated with reduced perinatal mortality and non-significantly with increased late preterm birth. LI was associated with increases in both late preterm birth and, in less-developed countries, perinatal mortality. Efforts to provide sufficient, but avoid excessive, access to provider-initiated delivery should be tailored to the local context.

Association of Shorter Height with Increased Risk of Ischaemic Placental Disease

BACKGROUND

Although adult height is inversely related with the risk of chronic disease, the association between maternal height and ischaemic placental disease remains unclear.

METHODS

We used the national, multicentre Japan Society of Obstetrics and Gynecology perinatal database to assess the risk of preeclampsia, placental abruption, and small for gestational age (SGA) births (birthweight < 10th percentile), which together constitute the syndrome 'ischaemic placental disease', in relation to self-reported height in 218 412 women with no underlying diseases before pregnancy, who delivered singletons in 2005-11. Height was categorised into quartiles as well as considered in linear terms, and its effect on each outcome was estimated using multivariable log binomial regression adjusted for the maternal characteristics.

RESULTS

The risk of preeclampsia, placental abruption, and SGA birth was inversely related to maternal height. In the adjusted model, mothers in the lowest quartile for height (<155 cm) were at higher risk of preeclampsia (relative risk (RR) 1.35, 95% confidence interval (CI) 1.25, 1.45), placental abruption (RR 1.20, 95% CI 1.07, 1.34), and SGA (RR 1.96, 95% CI 1.90, 2.03) compared with mothers in the highest quartile (>162 cm). When the association between height and outcomes was considered in linear terms, each 5 cm decrement in height was associated with an increased risk of preeclampsia (RR 1.11, 95% CI 1.09, 1.14), placental abruption (RR 1.04, 95% CI 1.01, 1.09), and SGA birth (RR 1.30, 95% CI 1.28, 1.31).

CONCLUSION

Shorter height was associated with an increased risk of preeclampsia, placental abruption, and SGA birth.

Social and anthropometric factors explaining racial/ethnical differences in birth weight in the United States

Though disparities in birth weight by race/ethnicity have been extensively reported in the United States, few studies have systematically investigated factors attributing to its variability. For 10,638,415 singleton infants born during 2009-2012 in the United States, we examined birth weight differences among 14 races and ethnicities (non-Hispanic white, non-Hispanic Black, American Indian, Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, Hawaiian, Guamanian, Mexican, Puerto Rican and Cuban), after sequentially adjusting for maternal, socio-economic and behavioral factors. Average birthweight of non-Hispanic white infants was 3381 g, while for other races/ethnicities birth weight ranged from being 289 g smaller in Japanese to 126 g larger in Samoan infants. Factors explaining differences of more than 50 grams in birth weight compared to white infants were: gestational age for black infants, height and body mass index for all Asian and Samoan mothers, and gestational weight gain for Japanese mothers. Difference in maternal age, parity, socioeconomic and behavioral characteristics did not account for significant portion of birthweight variations for any race. Our findings suggest that differences in maternal anthropometrics, gestational weight gain, and preterm birth rate, but not in maternal age, parity, socioeconomic or behavioral characteristics contribute to racial/ethnic differences in birthweight.

Assessing health-related quality of life in young Japanese children with chronic conditions: Preliminary validation of the DISABKIDS smiley measure

Background

Although there is an increasing need to investigate the health-related quality of life (HRQOL) of children and adolescents with chronic conditions in Japan, there is currently no standardized measure in which young children can directly answer questions about their HRQOL. The DISABKIDS Smiley measure uses face emoticons to measure HRQOL and distress caused by illness and related treatments among young children. We tested the reliability and validity of the DISABKIDS Smiley measure in a sample of young Japanese children.

Methods

After translating the child and parent questionnaires into Japanese, a pre-test was performed to test the content validity in accordance with guidelines from the DISABKIDS Group. In total, 60 child-parent pairs were recruited to participate in the survey. We measured internal consistency of the scales using Cronbach’s alpha as well as Guttman split-half, test-retest reliability using intraclass correlation coefficients (ICCs) at a two-week interval, and ICCs between child- and parent-reported scores. Convergent validity of the scale was also examined against the Kiddy-KINDL scale.

Results

Both child-reported and parent-reported scales showed good internal consistency and split-half reliability. Test-retest reliability of the child-reported version (ICC = 0.53, p = 0.004) was lower than that of the parent-reported version (ICC = 0.80, p < 0.001). Moderate to good agreement between child- and parent- reported scales was observed in both the first (ICC = 0.75, p < 0.001) and second administration (ICC = 0.71, p < 0.001). Moderate to very strong positive correlations were observed with the total score of the Kiddy-KINDL child-reported version (r = 0.51, p < 0.001), and facets of the Kiddy-KINDL parent-reported version (ranging from r = 0.364 to r = 0.60, p < 0.001) and total score (r = 0.71, p < 0.001).

Conclusions

The psychometric property of the instrument showed that the Japanese version of the DISABKIDS Smiley can be applied to assess the HRQOL of Japanese children with chronic conditions. Further investigation will be needed to explore the reliability and validity for repeated use of the instrument in clinical practice as an indicator of clinical significance.

International variations and trends in the treatment for retinopathy of prematurity

OBJECTIVE

To compare the rates of retinopathy of prematurity (ROP) and treatment of ROP by laser or intravitreal anti-vascular endothelial growth factor among preterm neonates from high-income countries participating in the International Network for Evaluating Outcomes (iNeo) of neonates.

METHODS

A retrospective cohort study was conducted on extremely preterm infants weighing <1500 g at 24⁰ to 27⁶ weeks' gestation who were admitted to neonatal units in Australia/New Zealand, Canada, Finland, Israel, Japan, Spain, Sweden, Switzerland, Tuscany (Italy) and the UK between 2007 and 2013. Pairwise comparisons of ROP treatment in survivors between countries were evaluated by Poisson and multivariable logistic regression analyses after adjustment for confounders. A composite outcome of death or ROP treatment was compared between countries using logistic regression and standardised ratios.

RESULTS

Of 48 087 infants included in the analysis, 81.8% survived to 32 weeks postmenstrual age, and 95% of survivors were screened for ROP. Rates of any ROP ranged from 25.2% to 91.0% in Switzerland and Japan, respectively, among those examined. The overall rate of those receiving treatment was 24.9%, which varied from 4.3% to 30.4%. Adjusted risk ratios for ROP treatment were lower for Switzerland in all pairwise comparisons, whereas Japan displayed significantly higher ratios. Comparisons of the composite outcome between countries revealed similar, but less marked differences.

CONCLUSIONS

Rates of any ROP and ROP treatment varied significantly between iNeo members, while an overall decline in ROP treatment was observed during the study period. It is unclear whether these variations represent differences in care practices, diagnosis and/or treatment thresholds.

Scoping review shows wide variation in the definitions of bronchopulmonary dysplasia in preterm infants and calls for a consensus

The use of different definitions for bronchopulmonary dysplasia (BPD) has been an ongoing challenge. We searched papers published in English from 2010 and 2015 reporting BPD as an outcome, together with studies that compared BPD definitions between 1978 and 2015. We found that the incidence of BPD ranged from 6% to 57%, depending on the definition chosen, and that studies that investigated correlations with long-term pulmonary and/or neurosensory outcomes reported moderate-to-low predictive values regardless of the BPD criteria.

CONCLUSION

A comprehensive and evidence-based definition for BPD needs to be developed for benchmarking and prognostic use.

Zika virus infection in pregnancy: a systematic review of disease course and complications

Objectives

To characterize maternal Zika virus (ZIKV) infection and complement the evidence base for the WHO interim guidance on pregnancy management in the context of ZIKV infection.

Methods

We searched the relevant database from inception until March 2016. Two review authors independently screened and assessed full texts of eligible reports and extracted data from relevant studies. The quality of studies was assessed using the Newcastle-Ottawa Scale (NOS) and the National Institute of Health (NIH) tool for observational studies and case series/reports, respectively.

Results

Among 142 eligible full-text articles, 18 met the inclusion criteria (13 case series/reports and five cohort studies). Common symptoms among pregnant women with suspected/confirmed ZIKV infection were fever, rash, and arthralgia. One case of Guillain-Barré syndrome was reported among ZIKV-infected mothers, no other case of severe maternal morbidity or mortality reported. Complications reported in association with maternal ZIKV infection included a broad range of fetal and newborn neurological and ocular abnormalities; fetal growth restriction, stillbirth, and perinatal death. Microcephaly was the primary neurological complication reported in eight studies, with an incidence of about 1% among newborns of ZIKV infected women in one study.

Conclusion

Given the extensive and variable fetal and newborn presentations/complications associated with prenatal ZIKV infection, and the dearth of information provided, knowledge gaps are evident. Further research and comprehensive reporting may provide a better understanding of ZIKV infection in pregnancy and attendant maternal/fetal complications. This knowledge could inform the creation of effective and evidence-based strategies, guidelines and recommendations aimed at the management of maternal ZIKV infection. Adherence to current best practice guidelines for prenatal care among health providers is encouraged, in the context of maternal ZIKV infection.

Electronic supplementary material

The online version of this article (doi:10.1186/s12978-017-0285-6) contains supplementary material, which is available to authorized users.

Impact of stillbirths on international comparisons of preterm birth rates: a secondary analysis of the WHO multi-country survey of Maternal and Newborn Health

Objective

To evaluate the extent to which stillbirths affect international comparisons of preterm birth rates in low‐ and middle‐income countries.

Design

Secondary analysis of a multi‐country cross‐sectional study.

Setting

29 countries participating in the World Health Organization Multicountry Survey on Maternal and Newborn Health.

Population

258 215 singleton deliveries in 286 hospitals.

Methods

We describe how inclusion or exclusion of stillbirth affect rates of preterm births in 29 countries.

Main outcome measures

Preterm delivery.

Results

In all countries, preterm birth rates were substantially lower when based on live births only, than when based on total births. However, the increase in preterm birth rates with inclusion of stillbirths was substantially higher in low Human Development Index (HDI) countries [median 18.2%, interquartile range (17.2–34.6%)] compared with medium (4.3%, 3.0–6.7%), and high‐HDI countries (4.8%, 4.4–5.5%).

Conclusion

Inclusion of stillbirths leads to higher estimates of preterm birth rate in all countries, with a disproportionately large effect in low‐HDI countries. Preterm birth rates based on live births alone do not accurately reflect international disparities in perinatal health; thus improved registration and reporting of stillbirths are necessary.

Tweetable abstract

Inclusion of stillbirths increases preterm birth rates estimates, especially in low‐HDI countries.

Inclusion of stillbirths increases preterm birth rates estimates, especially in low‐HDI countries.

Validation of a food frequency questionnaire for Japanese pregnant women with and without nausea and vomiting in early pregnancy

BACKGROUND

No previous study has shown the validity of a food frequency questionnaire (FFQ) in early pregnancy with consideration of nausea and vomiting during pregnancy (NVP). The aim of this study was to evaluate the validity of a FFQ in early pregnancy for Japanese pregnant women.

METHOD

We included 188 women before 15 weeks of gestation and compared estimated nutrient intake and food group intake based on a modified FFQ with that based on 3-day dietary records (DRs). Spearman's rank correlation coefficients, adjusting energy intake and attenuating within-person error, were calculated. Subgroup analysis for those with and without NVP was conducted. We also examined the degree of appropriate classification across categories between FFQ and DRs through division of consumption of nutrients and food groups into quintiles.

RESULTS

Crude Spearman's correlation coefficients of nutrients ranged from 0.098 (sodium) to 0.401 (vitamin C), and all of the 36 nutrients were statistically significant. In 27 food groups, correlation coefficients ranged from -0.015 (alcohol) to 0.572 (yogurt), and 81% were statistically significant. In subgroup analysis, correlation coefficients in 89% of nutrients and 70% of food groups in women with NVP and 97% of nutrients and 74% of food groups in women without NVP were statistically significant. On average, 63.7% of nutrients and 60.4% of food groups were classified into same or adjacent quintiles according to the FFQ and DRs.

CONCLUSIONS

The FFQ is a useful instrument, regardless of NVP, for assessing the diet of women in early pregnancy in Japan.

Dietary n-3 Polyunsaturated Fatty Acids in Late Pregnancy and Postpartum Depressive Symptom among Japanese Women

BACKGROUND

The use of n-3 polyunsaturated fatty acids (n-3PUFA) in preventive or therapeutic modalities for postpartum depression, especially long-chain types such as eicosapentaenoic acid (EPA) and a docosahexaenoic acid (DHA), is of considerable interest. High n-3PUFA consumption has been reported among pregnant Japanese women. Therefore, analysis of this group could provide important insights into the relationship between postpartum depression and dietary n-3PUFA consumption. To further examine the relationship between the risk of postpartum depression and n-3PUFA consumption, we conducted a prospective hospital-based birth cohort study in Japan.

DESIGN AND METHODS

Our prospective birth cohort study was performed at the National Center for Child Health and Development (NCCHD) in suburban Tokyo, Japan. Dietary n-3PUFA intake during late pregnancy was assessed by a semi-quantitative food questionnaire and participants were categorized by quintile distributions of n-3PUFA intake. A Japanese translation of the Edinburgh Postnatal Depression Scale was used to screen women for postpartum depression at 1 month after delivery (967 women) and at 6 months after delivery (710 women). We performed logistic regression analysis to examine the relationship between the risk of postpartum depression and n-3PUFA consumption after adjusting for confounding factors.

RESULTS

Significant associations between EPA, DHA, and n-3PUFA intakes in late pregnancy and postpartum depression at both 1 and 6 months after delivery were not observed.

CONCLUSION

This prospective study indicated that EPA, DHA, and n-3PUFA intake during late pregnancy was not associated with the risk of postpartum depression.