New Japanese neonatal anthropometric charts for gestational age at birth

Tocolytic treatment and maternal characteristics, obstetric outcomes, and offspring childhood outcomes among births at and after 37 weeks of gestation: the Japan environment and children's study

PURPOSE

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.

METHODS

Data for 63,409 women with singleton births at and after 37 weeks of gestation were analyzed using data from the Japan Environment and Children's Study (JECS). We compared maternal characteristics, obstetric outcomes, and offspring childhood outcomes between term and post-term births exposed and not exposed to tocolytic treatment. Additionally, multivariable logistic regression models were used to calculate adjusted odds ratios for offspring childhood outcomes with significant between-group differences in the univariable analysis, with term and post-term births without tocolytic agents as the reference group.

RESULTS

We observed differences in maternal characteristics and obstetric outcomes between term and post-term births exposed and not exposed to tocolytic treatment. The incidence of offspring childhood developmental disorders showed no significant between-group differences. However, participants exposed to tocolytic agents had higher incidence of offspring childhood allergic disorders. The adjusted odds ratio for any of the offspring childhood allergic disorders in term and post-term births with tocolytic agents was 1.08 (95% confidence interval, 1.03-1.13).

CONCLUSION

This study found no significant difference in the incidence of offspring developmental disorders between term and post-term births exposed and not exposed to tocolytic treatment. However, tocolytic treatment was associated with differences in maternal characteristics and obstetric outcomes, along with a marginal increase in the incidence of childhood allergic disorders in offspring.

Clinical characteristics of and growth hormone treatment effects on short stature with type 1 insulin-like growth factor receptor (IGF1R) gene alteration

Short stature with IGF-1 receptor (IGF1R) gene alteration is known as small-for-gestational-age (SGA) short stature with elevated serum IGF1 levels. Its prevalence and clinical characteristics remain unclear. No adapted treatment is available for short stature related to IGF1R gene alteration in Japan, and genetic testing is not yet widely accessible. We investigated short stature with IGF1R gene alterations and analyzed the clinical data of 13 patients using the results of questionnaires issued to the Japanese Society for Pediatric Endocrinology. Four cases were caused by a deletion of chromosome 15q26.3, and eight were caused by heterozygous pathogenic variants in the IGF1R gene. Cases with deletions showed a more severe degree of growth impairment (-4.5 ± 0.43 SD) than those caused by pathological variants (-2.71 ± 0.15 SD) and were accompanied by neurodevelopmental delay. However, cases caused by pathological variants lacked distinctive features. Only three of the 12 cases demonstrated serum IGF1 values exceeding +2 SD, and the other three had values below 0 SD. Four patients did not meet the criteria for SGA at birth. Six patients received GH therapy for SGA short stature and showed improvement in growth rate without any side effects or elevated serum IGF1 levels during treatment. Elevated IGF1 levels (over +2 SD) after GH treatment should be considered a suspicious finding. Owing to the lack of distinctive features, there was a possibility of undiagnosed cases of this condition. Promoting genetic testing and clinical trials on GH administration for this condition is recommended.

Association Between Gestational Weeks, Initial Maternal Perception of Fetal Movement, and Individual Interoceptive Differences in Pregnant Women: Cross-Sectional Study

BACKGROUND

Interoception encompasses the conscious awareness of homeostasis in the body. Given that fetal movement awareness is a component of interoception in pregnant women, the timing of initial detection of fetal movement may indicate individual differences in interoceptive sensitivity.

OBJECTIVE

The aim of this study is to determine whether the association between the gestational week of initial movement awareness and interoception can be a convenient evaluation index for interoception in pregnant women.

METHODS

A cross-sectional study was conducted among 32 pregnant women aged 20 years or older at 22-29 weeks of gestation with stable hemodynamics in the Obstetric Outpatient Department. Interoception was assessed using the heartbeat-counting task, with gestational weeks at the first awareness of fetal movement recorded via a questionnaire. Spearman rank correlation was used to compare the gestational weeks at the first awareness of fetal movement and heartbeat-counting task scores.

RESULTS

A significant negative correlation was found between the gestational weeks at the first fetal movement awareness and heartbeat-counting task performance among all participants (r=-0.43, P=.01) and among primiparous women (r=-0.53, P=.03) but not among multiparous women.

CONCLUSIONS

Individual differences in interoception appear to correlate with the differences observed in the timing of the first awareness of fetal movement.

Delivery room intubation and neurodevelopment among extremely preterm infants

BACKGROUND

The impact of delivery room intubation (DRI) on neurodevelopment in extremely preterm infants remains unclear.

METHODS

We retrospectively analyzed data for infants born at 24-27 gestational weeks between 2003 and 2018. The primary outcome was neurodevelopmental impairment (NDI), defined as cerebral palsy or hearing, visual, or cognitive impairment at age 3 years. Secondary outcomes were NDI components and death before and after discharge from the neonatal intensive care unit. We conducted robust Poisson regression analyses, adjusting for perinatal confounders.

RESULTS

The full cohort included 4397 infants with NDI data, of whom 3703 were intubated in the delivery room and 694 were not intubated in the delivery room. The mean gestational age and birth weight were 26.0 ± 1.1 weeks and 778 ± 184 g for infants with DRI and 26.6 ± 1.0 weeks and 873 ± 184 g for infants without DRI. Compared with infants without DRI, those with DRI had a higher risk for NDI (32.4% vs. 23.3%; adjusted risk ratio 1.18, 95% confidence interval: 1.01-1.37). There were no differences in secondary outcomes between infants with and without DRI.

CONCLUSIONS

DRI was associated with an increased risk for NDI at age 3 years among extremely preterm infants.

IMPACT

Few studies have examined the impact of delivery room intubation on neurodevelopment in infants born extremely preterm, and the results have been inconsistent. A total of 4397 infants born at 24-27 gestational weeks who had neurodevelopmental data at age 3 years were included in the present study. The present study found that delivery room intubation was associated with an increased risk for neurodevelopmental impairment at age 3 years among extremely preterm infants.

Predictability of the neurodevelopmental assessment based on the Kyoto Scale of Psychological Development 2001 at 18-24 months of corrected age and 3 years of age in identifying cognitive impairment at 6 years of age in very preterm infants: A retrospective study at a Japanese tertiary center

BACKGROUND

It is unknown how accurately the current Japanese classification system for neurodevelopmental delay based on the assessment with the Kyoto Scale of Psychological Development (KSPD) at toddlerhood and pre-school periods predicts cognitive impairment at school age.

METHODS

This single-center retrospective cohort study enrolled infants born at 22-29 weeks of gestational age. At 18-24 months of corrected age and 3 years of age, the patients were categorized according to the current Japanese criteria for neurodevelopmental delay based on their overall developmental quotient calculated using the KSPD-2001. Cognitive impairment at 6 years of age was classified according to the calculated or estimated full-scale intelligence quotient. The predictability of the current Japanese classification of neurodevelopmental delay for cognitive impairment at 6 years of age was investigated.

RESULTS

Of 566 eligible patients, 364 (64 %) completed the protocol. The current classification for the neurodevelopmental delay showed significant agreement with the severity of cognitive impairment at 6 years of age. The sensitivity and specificity of the KSPD-2001-based assessment for any cognitive impairment at 6 years of age were 0.64 and 0.74 at 18-24 months of corrected age and 0.83 and 0.70 at 3 years of age. The corresponding sensitivity and specificity for moderate/severe cognitive impairment were 0.51 and 0.96 at 18-24 months of corrected age and 0.68 and 0.95 at 3 years of age.

CONCLUSION

The KSPD-2001 is a useful tool to predict the severity of cognitive impairment at school age.

Gestational Age and Neurodevelopmental Delay in Term Births at 6 and 12 Months: The Japan Environment and Children's Study (JECS)

BACKGROUND

In the recent years, a high risk of developmental delay not only in very low birth weight infants and late preterm infants but also in early term infants (37-38 weeks) have increasingly been reported. However, in Japan, there are virtually no studies regarding the development delays in early term infants.

METHODS

This study used the data from the Japan Environment and Children's Study (JECS), a birth cohort study conducted in Japan. Data were selected for analysis from the records of 104,065 fetal records. The risk of neurodevelopmental delays at 6 months and 12 months after birth was evaluated using multivariate analysis for infants of various gestational ages, using the 40th week of pregnancy as a reference value. Neurodevelopment was evaluated at 6 months and 12 months after birth using the Ages and Stages Questionnaires, Japanese translation (J-ASQ-3).

RESULTS

The proportion of infants born at a gestational age of 37 to 38 weeks who did not reach the J-ASQ-3 score cutoff value was significantly higher in all areas at both 6 months and 12 months after birth, when compared to that of infants born at 40 weeks. The odds ratio decreased at 12 months after birth compared to that at 6 months after birth.

CONCLUSION

Early term infants in Japan are at an increased risk of neurodevelopmental delay at 12 months after birth.

Intrauterine twin environment and genetic factors subliminally affecting general movements in preterm infants

BACKGROUND

Understanding background factors is beneficial for interpreting general movements (GMs). This study examines the factors involved in preterm-writhing GMs by comparing twins and singletons.

METHOD

The subjects were 107 infants cared for at Oita University. The cohort consisted of very-low-birth-weight infants, including twins with a birth weight < 2000 g. The median gestational age (GA) was 29 weeks 1 day. The subjects consisted of 75 singletons, 32 twins (16 pairs), 20 monochorionic twins (M-twins), and 12 dichorionic twins (D-twins). GMs were scored according to the GMs optimality score (GMOS) and integrated into 6 items: the quality, neck-trunk and space, amplitude-speed, rotation, onset-offset and cramped, and tremulous score at 32-34 weeks, 35-36 weeks, and 37-42 weeks' GA. A hierarchical cluster analysis was performed using integrated GMOS, and the characteristics of clusters were examined according to clinical backgrounds.

RESULTS

Three clusters were identified. Cluster 1 was characterized by good-quality GMs, cluster 2 by a poor repertoire but optimal space and rotatory components, and cluster 3 by overall poor-quality GMs, respectively. The mean GMOSs were 36.6, 31.8 and 24.3 in clusters 1, 2, and 3, respectively. There were no marked differences in proportions within clusters with respect to sex and twins. Small-for-gestational age (SGA) was significantly more frequent in cluster 3 at 32-34 weeks' GA than in other clusters. Perinatal brain injury had a significantly lower proportion in cluster 1 and a higher proportion in cluster 3 at 35-36 weeks' GA and 37-42 weeks' GA. M-twin pairs tended to belong to the same clusters at 35-36 weeks' GA.

CONCLUSION

Preterm writhing GMs are associated with SGA and perinatal brain injury. Cluster matching in M-twins suggests that certain genetic factors may substantially influence GMs.

New Roles for Albumin/Globulin Ratio in the Early-Onset Hyperbilirubinemia among Infants Born Weighing 1,000 to 2,499 Grams

INTRODUCTION

Early-onset hyperbilirubinemia (EOH) is a clinical issue for premature infants. We predicted that EOH management would be improved by fast results from common laboratory tests. Total serum bilirubin (TSB) level and the albumin/globulin ratio may contribute to improving the management of EOH.

OBJECTIVE

The aim of the study is to examine the relationship between EOH and perinatal variables among infants born weighing 1,000 to 2,499 g.

STUDY DESIGNS

A single center study was undertaken at Ohta Nishinouchi Hospital between April 1, 2016 and January 31, 2022, using blood samples prospectively collected from infants admitted to the neonatal intensive care unit that were assessed by univariate analyses and multivariate logistic regression analysis. Due to a correlation between gestational age (GA) and birth weight (BW), each variable was entered separately into Model 1 (including GA) and 2 (including BW).

RESULTS

A total of 508 infants were analyzed (270 in the non EOH group and 238 in the EOH group). No infants experienced feto-maternal transfusion syndrome or hemolytic diseases such as blood type (ABO or Rh) incompatibility or glucose-6-phosphate dehydrogenase deficiency during perinatal period. Significant relationships were observed between EOH and BW (p <0.01, odds ratio [OR], 0.997; 95% confidence interval [CI], 0.996-0.997), albumin (p <0.01, OR, 0.278; 95% CI, 0.129-0.599), albumin/globulin ratio (p <0.01, OR, 2.695; 95% CI, 1.378-5.270), TSB (p <0.01, OR, 2.774; 95% CI, 1.795-4.287), and antenatal corticoid therapy (p = 0.02, OR, 1.852; 95% CI, 1.108-3.097) in Model 2. Per receiver operating characteristic curves, an albumin/globulin ratio of 1.84 could predict EOH at a sensitivity of 50.0% and specificity of 75.6% (AUC = 0.652, p <0.01, 95% CI, 0.603-0.700).

CONCLUSION

Albumin/globulin ratio among infants born weighing 1,000 to 2,499 g may be a useful indicator of EOH.

KEY POINTS

· Early-onset hyperbilirubinemia (EOH) is a clinical issue for premature infants.. · EOH management expected to be improved through the use of common laboratory tests.. · Albumin/globulin ratio among low birth weight infants may be a useful indicator of EOH..

Intrauterine exposure to chorioamnionitis and neuroanatomical alterations at term-equivalent age in preterm infants

PURPOSE

Infants born to mothers with chorioamnionitis (CAM) are at increased risk of developing adverse neurodevelopmental disorders in later life. However, clinical magnetic resonance imaging (MRI) studies examining brain injuries and neuroanatomical alterations attributed to CAM have yielded inconsistent results. We aimed to determine whether exposure to histological CAM in utero leads to brain injuries and alterations in the neuroanatomy of preterm infants using 3.0- Tesla MRI at term-equivalent age.

METHODS

A total of 58 preterm infants born before 34 weeks of gestation at Nagoya University Hospital between 2010 and 2018 were eligible for this study (CAM group, n = 21; non-CAM group, n = 37). Brain injuries and abnormalities were assessed using the Kidokoro Global Brain Abnormality Scoring system. Gray matter, white matter, and subcortical gray matter (thalamus, caudate nucleus, putamen, pallidum, hippocampus, amygdala, and nucleus accumbens) volumes were evaluated using segmentation tools (SPM12 and Infant FreeSurfer).

RESULTS

The Kidokoro scores for each category and severity in the CAM group were comparable to those observed in the non-CAM group. White matter volume was significantly smaller in the CAM group after adjusting for covariates (postmenstrual age at MRI, infant sex, and gestational age) (p = 0.007), whereas gray matter volume was not significantly different. Multiple linear regression analyses revealed significantly smaller volumes in the bilateral pallidums (right, p = 0.045; left, p = 0.038) and nucleus accumbens (right, p = 0.030; left, p = 0.004) after adjusting for covariates.

CONCLUSIONS

Preterm infants born to mothers with histological CAM showed smaller volumes in white matter, pallidum, and nucleus accumbens at term-equivalent age.

Timing of Elective Cesarean Section and Neonatal Outcomes in Term Singleton Deliveries: A Single-Center Experience

OBJECTIVE

This study aimed to evaluate the timing of elective cesarean sections at 37 to 41 weeks from a tertiary hospital in Japan. The primary outcome was the rate of adverse neonatal outcomes, especially focusing on neonates delivered at 38 weeks of gestation.

STUDY DESIGN

The study population was drawn from singleton pregnancies delivered following planned cesarean birth at the Fukuda Hospital from 2012 to 2019. Information on deliveries was obtained from the hospital database, which contains clinical, administrative, laboratory, and operating room databases.

RESULTS

After excluding women with chronic conditions, maternal complications, indications for multiple births, or a neonate with an anomaly, 2,208 neonates remained in the analysis. Among adverse neonatal outcomes, the rate was significantly higher in neonates delivered at 37 weeks of gestation (unadjusted odds ratio [OR] = 13.22 [95% confidence interval [CI]: 6.28, 27.86], p < 0.001) or 38 weeks of gestation (unadjusted OR = 1.82 [95% CI: 1.04, 3.19], p = 0.036) compared with neonates delivered at 39 to 41 weeks. The adjusted risk of any adverse outcome was significantly higher at 380-1/7 weeks (adjusted OR = 2.40 [95% CI: 1.35, 4.30], p = 0.003) and 382-3/7 weeks (adjusted OR = 1.89 [95% CI: 1.04, 3.44], p = 0.038) compared with neonates delivered at 39 to 41 weeks, respectively.

CONCLUSION

Our findings suggest that elective cesarean sections might be best scheduled at 39 weeks or later. When considering a cesarean at 38 weeks, it appears that 384/7 weeks of gestation or later could be a preferable timing in the context of reducing neonatal risks. However, as the composite outcome includes mostly minor conditions, the clinical significance of this finding needs to be carefully interpreted.

KEY POINTS

· Timing of elective cesarean sections from 37 to 41 weeks was evaluated in a Japanese tertiary hospital.. · Neonates delivered at 37 and 38 weeks had higher adverse outcome rates compared with 39 to 41 weeks.. · Scheduling elective cesarean sections at least 384/7 weeks or later may reduce neonatal risk..

Small for Gestational Age Affects Outcomes on Singletons and Inborn Births in Extremely Preterm Infants: A Japanese Cohort Study

OBJECTIVE

This study aimed to compare the short- and long-term outcomes of extremely preterm small for gestational age (SGA) infants and appropriate for gestational age (AGA) infants in Japan.

STUDY DESIGN

We retrospectively assessed 434 SGA and 1,716 AGA infants born at 22 to 27 weeks of gestational age (GA) and examined their outcomes on singletons and inborn births between 2003 and 2012. Infants were followed-up for 3 years, and the clinical characteristics and outcomes were compared. Fisher's exact and Student's t-tests were used for independent sample comparison. Logistic regression was used to identify associated factors.

RESULTS

The prevalence of intraventricular hemorrhage ≥ grade 3 was significantly lower (adjusted odds ratio [aOR]: 0.28; 95% confidence interval [CI]: 0.11 - 0.72), and the prevalence of bronchopulmonary dysplasia at 36 weeks of GA and the need for home oxygen therapy were significantly higher (aOR: 2.20; 95% CI: 1.66 - 2.91 and aOR: 2.46; 95% CI: 1.75-3.47, respectively) in SGA infants than in AGA infants. SGA infants born at 24 to 25 weeks of GA had a significantly higher prevalence of developmental quotient (DQ) < 70 (aOR: 1.73; 95% CI: 1.08 - 2.77). Those born at 26 to 27 weeks of GA showed a significantly higher prevalence of cerebral palsy (CP) and visual impairment (aOR: 2.31; 95% CI: 1.22 - 4.40 and aOR: 2.61; 95% CI: 1.21 - 5.61, respectively).

CONCLUSION

In SGA infants, birth at 24 to 25 weeks of GA is an independent risk factor for DQ < 70, and birth at 26 to 27 weeks of GA is an independent risk factor for CP and visual impairment. However, we did not consider nutritional and developmental factors, and a longer follow-up would help assess neurodevelopmental outcomes.

KEY POINTS

· SGA is a risk factor for poor outcomes.. · In SGA infants, birth at 25 to 26 weeks is a risk factor for low a DQ.. · In SGA infants, birth at 26 to 27 weeks is a risk factor for CP..

Nonreassuring fetal status during labor and offspring's childhood neurodevelopment at 3 years of age: The Japan Environment and Children's Study

OBJECTIVE

Although prior attempts have failed to identify the beneficial effects of intensive fetal monitoring on cerebral palsy, the association between nonreassuring fetal status (NRFS) during labor and the incidence of long-term neurodevelopmental delays in offspring remains unclear. This study aimed to evaluate this association using a nationwide birth cohort.

METHODS

Data from 72 869 women with singleton deliveries at and after 37 weeks of gestation from the Japan Environment and Children's Study (2011-2014) were analyzed. Multivariable logistic regression models were used to analyze the odds ratios (ORs) for neurodevelopmental delays using the Ages & Stages Questionnaire (Third Edition) in offspring aged 3 years.

RESULTS

The adjusted ORs for personal-social problems were 1.52 (95% confidence interval [CI], 1.06-2.16) for offspring delivered vaginally by nulliparous mothers and 1.51 (95% CI, 1.05-2.18) (for males, 1.70 [95% CI, 1.15-2.50]) for those delivered via cesarean section. No significant changes in adjusted ORs for neurodevelopmental delays were observed among participants without neonatal Apgar scores (ASs) <7 and without umbilical arterial pH (UmA-pH) <7.20.

CONCLUSION

NRFS during labor was associated with an increased incidence of personal-social problems in offspring aged 3 years. However, this association was not confirmed after excluding participants with neonatal ASs <7 and UmA-pH <7.20. The association between NRFS and offspring's neurodevelopmental delays might vary based on delivery settings, offspring sex, and short-term neonatal outcomes.

Association of maternal obesity with growth of fetal fractional limb volume

BACKGROUND

Maternal obesity influences birth weight and newborn adiposity. Fetal fractional limb volume has recently been introduced as a useful parameter for the proxy of fetal adiposity. However, the association between maternal adiposity and the growth of fetal fractional limb volume has not been examined.

AIMS

To investigate the association of maternal pre-pregnancy BMI with the growth of fetal fractional limb volume.

STUDY DESIGN

Prospective cohort study.

SUBJECTS

Women with singleton uncomplicated pregnancies enrolled between July 2017 and June 2020.

OUTCOME MEASURES

Fetal fractional limb volume was assessed between 20 and 40 weeks' gestation, measured as cylindrical limb volume based on 50 % of the total diaphysis length. The measured fractional limb volume at each gestational week were converted to z-scores based on a previous report. The association between pre-pregnancy BMI and fetal fractional limb volume was examined. Maternal age, parity, gestational weight gain and fetal sex were considered as potential confounding variables.

RESULTS

Ultrasound scans of 455 fractional arm volume and thigh volume were obtained. Fractional limb volume increased linearly until the second trimester of gestation, then increased exponentially in the third trimester. Maternal pre-pregnancy BMI was significantly correlated with z-scores of fractional arm volume and thigh volume across gestation. The post-hoc analysis showed the association between pre-pregnancy BMI and fractional arm volume was significant especially between 34 and 40 weeks.

CONCLUSIONS

Maternal obesity influences the growth pattern of fetal fractional limb volume. Fractional arm volume may potentially provide a useful surrogate marker of fetal nutritional status in late gestation.

Prolonged renal function impairment in infants born during the peri-viable period: A retrospective longitudinal cohort study

BACKGROUND

The number of infants born during the peri-viable period who survive has been increasing.

AIM

To clarify renal function in infants from the time of birth during the peri-viable period until their due date.

STUDY DESIGN

This retrospective cohort study was conducted at a single center.

SUBJECTS

We reviewed the data of infants born at ≤28 weeks of gestation between 2018 and 2022 at our hospital. The infants were divided into the following groups: born at 22-24 weeks vs. 25-28 weeks (appropriate-for-gestational age [AGA] infants), and AGA infants vs. small-for-gestational age (SGA) infants (born at 22-28 weeks).

OUTCOME MEASURES

We compared the perinatal data and renal function of the infants from birth until their due date.

RESULTS

Eighty-one infants were included. Their serum creatinine, fractional excretion of sodium, and urine glucose levels were high or positive soon after birth but gradually improved. The urine albumin level was significantly higher among AGA infants born at 22-24 weeks, even at term equivalent age, than among those born at 25-28 weeks.

CONCLUSIONS

Persistent renal insufficiency was observed even around the term equivalent age in peri-viable infants. Follow-up data collected after the neonatal period should be investigated in these infants.

Prognosis of 22- and 23-Gestational-Week-Old Infants at Our Facility: A Retrospective Cohort Study

OBJECTIVE

This study aimed to compare inborn infants aged 22 and 23 gestational weeks at our hospital to assess for differences in survival and long-term prognosis.

STUDY DESIGN

We retrospectively analyzed 22- and 23-gestational-weeks-old infants born in our hospital between January 2011 and December 2018. The prognosis of inborn infants in Japan was also calculated using the Neonatal Research Network of Japan (NRNJ) data during the same period.

RESULTS

The survival rates at our institution's neonatal intensive care unit discharge, including stillbirth, were 72 and 89% at 22 and 23 gestational weeks, respectively. The mortality rate and neurodevelopmental impairment (NDI) rate at 3 years of age, including stillbirth, were 58 and 32% at 22 and 23 weeks, respectively. Cerebral palsy, mental developmental retardation, visual impairment, and hearing impairment defined NDI. The prognosis at our hospital was better than the average calculated using NRNJ data. Survival rates varied among facilities, and some facilities had survival rates similar to that of our hospital.

CONCLUSION

The prognosis of 22-gestational-week-old inborn infants was inferior to that of 23 gestational weeks in our institution but was better than previously reported. If aggressive treatment is provided, survival without sequelae can be fully expected even for 22-gestational-week-old infants.

KEY POINTS

· We examined babies of gestation ages 22 and 23 weeks.. · We examined the survival and neurological prognoses.. · We compared our facility with that in entire Japan..

An Application of a Physiologically Based Pharmacokinetic Approach to Predict Ceftazidime Pharmacokinetics in a Pregnant Population

Physiological changes during pregnancy can alter maternal and fetal drug exposure. The objective of this work was to predict maternal and umbilical ceftazidime pharmacokinetics during pregnancy. Ceftazidime transplacental permeability was predicted from its physicochemical properties and incorporated into the model. Predicted concentrations and parameters from the PBPK model were compared to the observed data. PBPK predicted ceftazidime concentrations in non-pregnant and pregnant subjects of different gestational weeks were within 2-fold of the observations, and the observed concentrations fell within the 5th-95th prediction interval from the PBPK simulations. The calculated transplacental clearance (0.00137 L/h/mL of placenta volume) predicted an average umbilical cord-to-maternal plasma ratio of 0.7 after the first dose, increasing to about 1.0 at a steady state, which also agrees well with clinical observations. The developed maternal PBPK model adequately predicted the observed exposure and kinetics of ceftazidime in the pregnant population. Using a verified population-based PBPK model provides valuable insights into the disposition of drug concentrations in special individuals that are otherwise difficult to study and, in addition, offers the possibility of supplementing sparse samples obtained in vulnerable populations with additional knowledge, informing the dosing adjustment and study design, and improving the efficacy and safety of drugs in target populations.

Early infantile spontaneous movement in very low birthweight infants is associated with sensory characteristics at the corrected age of 3 years

AIM

To clarify the relationship between early infantile spontaneous movement of very-low-birth-weight infants (VLBWIs) and sensory characteristics in childhood.

STUDY DESIGN

Prospective cohort study. We investigated the association between the Motor Optimality Score-Revised (MOS-R), a detailed assessment of general movements (GMs) at the corrected age of 9-17 weeks and the Infant/Toddler Sensory Profile Japanese version (ITSP-J) at the corrected age of 3 years. A multiple regression analysis was performed to examine the correlation of ITSP-J and MOS-R with patient clinical background factors.

SUBJECTS

Fifty-three VLBWIs (median gestational age: 28 weeks, 6 days; median birth weight: 997 g) who were managed at the NICU of Oita University from September 2013 to June 2019.

RESULTS

A multiple regression analysis revealed that the ITSP-J subscale in the sensory section of visual score was significantly correlated with the age-adequate movement repertoire subscore of MOS-R, and in the sensory section of vestibular score was correlated with the fidgety subscore of MOS-R. For both visual and vestibular section scores, intraventricular hemorrhage (IVH) showed an independent association with the MOS-R subscore.

CONCLUSION

Spontaneous movement characteristics in early infancy were associated with sensory characteristics in early childhood.

Postneonatal mortality of severely small for gestational age extremely low birth weight infants

BACKGROUND

Infants born with weights below the 10th percentile of the expected birth weight for gestational age, defined as small for gestational age (SGA), have an increased risk of neonatal mortality and prematurity-related complications. However, the relationship between SGA and postneonatal (28 days to <1 year) mortality among extremely low birth weight infants (ELBWIs) remains uncertain. Hence, this study aimed to investigate the association between birth weight percentiles and postneonatal mortality in ELBWIs.

METHODS

A cohort of ELBWIs with a gestational age greater than 23 weeks who were admitted to Osaka Women's and Children's Hospital between 2008 and 2019 were considered eligible. Infants with major congenital anomalies, those large for their gestational age, or those who died within 28 days of birth were excluded. Baseline characteristics and outcomes of the three groups of ELBWIs-severe SGA (sSGA; birth weight, <3rd percentile), moderate SGA (mSGA; birth weight, 3rd to <10th percentile), and appropriate for gestational age (AGA; birth weight, 10th to <90th percentile)-were compared. Logistic regression analysis was used to identify perinatal factors associated with postneonatal mortality in sSGA infants.

RESULTS

sSGA ELBWIs demonstrated higher incidence of meconium obstruction (25% vs. 8.3% vs. 7.6%, P < 0.001), cholestasis (21% vs. 4.2% vs. 9.7%, P < 0.003), and postneonatal mortality (7.3% vs. 0% vs. 0.7%, P < 0.004) than mSGA and AGA ELBWIs. In the logistic regression analysis, cholestasis (odds ratio, 30.1; 95% confidence interval, 2.98-304) and sepsis (odds ratio, 13.5; 95% confidence interval, 1.06-173) were significantly related to postneonatal mortality among ELBWIs with sSGA. The leading cause of postneonatal mortality in sSGA ELBWIs was liver failure (55.5%).

CONCLUSION

sSGA ELBWIs exhibited a higher rate of postneonatal mortality compared to mSGA and AGA ELBWIs. Therefore, strategies aimed at preventing liver dysfunction in severely cholestatic ELBWIs with sSGA are necessary.

Investigation of optimal weight gain during pregnancy: A retrospective analysis of the Japanese perinatal registry database

AIM

This study aimed to determine the weight gain during pregnancy that minimizes the predicted probability of various perinatal adverse events according to the pre-pregnancy body mass index (BMI) and make recommendations for optimal weight gain in Japan.

METHODS

The Japan Society of Obstetrics and Gynecology perinatal database for 2015-2017 was used. From the 719 723 deliveries included in this database, parturients with underlying diseases or missing data were excluded, and 419 114 deliveries were analyzed. A questionnaire survey was also conducted to weigh each perinatal adverse event. For each of the nine outcomes, a restricted cubic spline model was made to estimate the association between the "expected gestational weight gain at 40 weeks" and the outcome risk.

RESULTS

Since the classes of medical facilities were generally the same, weights were assigned according to the mean of the questionnaires rather than by the class of the facility. For each pre-pregnancy BMI, the weight gains during pregnancy that minimized the predicted probability of various adverse perinatal events were 12-15, 10-13, 7-10, and upper limit of 5 kg for the underweight, normal-weight, obese 1, and obese ≥2 groups, respectively.

CONCLUSIONS

The weight gain during pregnancy that minimizes the predicted probability of various perinatal adverse events according to the pre-pregnancy BMI was established.

Impact of interpregnancy weight changes and perinatal outcomes: A retrospective study in Japan

Previous studies have shown that interpregnancy weight fluctuations impact perinatal outcomes. In order to examine this in Japanese women, we analyzed the data of 2,861 women in their first and second pregnancies who delivered singletons between 2000 and 2022. We compared the second pregnancy perinatal outcomes of women whose interpregnancy body mass index (BMI) change was -1 to 1 unit with those of women whose BMI change was < -1 or ≥ 1 unit. An interpregnancy BMI change ≥ 1 unit was associated with an increased risk of developing gestational diabetes mellitus (adjusted odds ratio [aOR], 1.51; 95% confidence interval [CI], 1.18-1.95) and delivering a large for gestational age neonate (aOR, 1.67; 95% CI, 1.15-2.42) but a decreased risk of preterm birth (aOR, 0.66; 95% CI, 0.46-0.95). An interpregnancy BMI change < -1 unit was associated with a decreased risk of developing gestational diabetes mellitus (aOR, 0.51; 95% CI, 0.31-0.85). In a subgroup analysis of three groups divided according to prepregnancy BMI, interpregnancy BMI changes ≥ 1 unit in women with a BMI of < 18.5 kg/m2 before their first pregnancy were associated with a remarkable risk reduction of developing preterm birth (aOR, 0.30; 95% CI, 0.11-0.81). Interpregnancy BMI changes < -1 unit in women with a BMI of ≥ 25 kg/m2 before their first pregnancy were associated with a remarkable risk reduction of developing gestational diabetes mellitus (aOR, 0.33; 95% CI, 0.12-0.88). Weight gain during interpregnancy period was related to an increased risk of gestational diabetes mellitus and delivery of a large-for-gestational-age neonate, whereas weight loss was related to a decreased risk of developing gestational diabetes mellitus. These results indicate the importance of interpregnancy weight control as part of preconception care; therefore, women considering additional pregnancies should be educated on the importance of maintaining a healthy weight.

Association of cesarean section and infectious outcomes among infants at 1 year of age: Logistic regression analysis using data of 104,065 records from the Japan Environment and Children's Study

BACKGROUND

There has been a recent decrease in the prevalence of infectious diseases in children worldwide due to the usage of vaccines. However, the association between cesarean delivery and infectious diseases remains unclear. Here, we aimed to clarify the association between cesarean delivery and the development of infectious diseases.

METHODS

This study is a cross-sectional study. We used data from the Japan Environment and Children's Study, which is a prospective, nationwide, government-funded birth cohort study. The data of 104,065 records were included. Information about the mode of delivery, central nervous system infection (CNSI), otitis media (OM), upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI), gastrointestinal infection (GI), and urinary tract infection (UTI) was obtained from questionnaires and medical records transcripts. Multiple logistic regression analysis was used to assess the association between cesarean delivery and CNSI, OM, URTI, LRTI, GI, and UTI risk.

RESULTS

We included a total of 74,477 subjects in this study, of which 18.4% underwent cesarean deliveries. After adjusting for the perinatal, socioeconomic, and postnatal confounding factors, children born by cesarean delivery did not have an increased risk of developing CNSI (95% confidence interval [CI] 0.46-1.35), OM (95% CI 0.99-1.12), URTI (95% CI 0.97-1.06), LRTI (95% CI 0.98-1.15), GI (95% CI 0.98-1.11), or UTI (95% CI 0.95-1.45).

CONCLUSIONS

This nationwide cohort study did not find an association between cesarean delivery and CNSI, OM, URTI, LRTI, GI, and UTI. However, further studies are needed to evaluate the role of cesarean delivery in the development of infectious diseases.

The serum thioredoxin-1 levels are not associated with bronchopulmonary dysplasia and retinopathy of prematurity

BACKGROUND

We hypothesized that the serum TRX-1 in extremely preterm infants (EPIs) after birth was associated with the development of severe bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP).

METHODS

This single-centered retrospective study enrolled EPIs treated at our institution. Serum TRX-1 concentrations of the residual samples taken on admission, day 10-20 of life, and 36-40 weeks of postmenstrual age (PMA) were measured with an enzyme-linked immunosorbent assay.

RESULTS

The serum TRX-1 levels on admission were not different between the severe BPD (n = 46) and non-severe BPD groups (n = 67): [median (interquartile range) 147 (73.0-231) vs. 164 (80.5-248) ng/mL] (P = 0.57). These had no significant difference between the severe ROP (n = 47) and non-severe ROP groups (n = 66): [164 (71.3-237) vs. 150 (80.9-250) ng/mL] (P = 0.93). The TRX-1 levels at 10-20 days of life and 36-40 weeks of PMA also had no association with the development of severe BPD and ROP.

CONCLUSION

The serum TRX-1 levels after birth are not predictive of severe BPD and ROP.

IMPACT

Serum thioredoxin-1 levels in extremely preterm infants on the day of birth are lower than those in term or near-term infants hospitalized for transient tachypnea of the newborn. In extremely preterm infants, the serum thioredoxin-1 levels on the day of birth, at 10-20 days of life, and at postmenstrual age of 36-40 weeks were not associated with severe bronchopulmonary dysplasia and retinopathy of prematurity. The thioredoxin system is under development in extremely preterm infants; however, the serum thioredoxin-1 level is not predictive for severe bronchopulmonary dysplasia and retinopathy of prematurity.

Range of protein induced by vitamin K absence or antagonist-II levels in neonates at birth

Protein induced by vitamin K absence or antagonist-II (PIVKA-II) is avitamin K (VK) deficiency indicator in neonates. However, PIVKA-II detection frequency in neonatal blood at birth and the correlation between PIVKA-II and gestational age are unclear. We retrospectively analyzed infants admitted to our institution between June 1, 2018, and March 31, 2022, whose clinical and PIVKA-II data were available, and classified them into preterm and term infant groups. Overall incidence of PIVKA-II-positive cases (≥ 50 mAU/mL) was 42.8%, including 0.6% apparent VK deficiency (≥ 5000 mAU/mL), 3.1% experimental VK deficiency (1000-4999 mAU/mL), and 10.7% latent VK deficiency (200-999 mAU/mL) cases. Incidence of PIVKA-II-positive cases was significantly higher in the term group than in the preterm group (49.4% vs. 29.7%, p < 0.001). Gestational age correlated with PIVKA-II levels (r2 = 0.117, p < 0.0001). Median serum PIVKA-II levels and incidence of PIVKA-II-positive cases (≥ 50 mAU/mL, 16.4%) were lower at 5 days after birth than at birth, possibly reflecting the postnatal VK prophylaxis impact. Only one infant was diagnosed with VK deficiency bleeding (PIVKA-II levels, at birth: 10,567 mAU/mL; at day 5: 2418 mAU/mL). Thus, serum PIVKA-II levels after birth weakly correlated with gestational age. VK deficiency was more common in term infants than in preterm infants.

The Population-Attributable Fractions of Small-for-Gestational-Age Births: Results from the Japan Birth Cohort Consortium

A fetal growth restriction is related to adverse child outcomes. We investigated risk ratios and population-attributable fractions (PAF) of small-for-gestational-age (SGA) infants in the Japanese population. Among 28,838 infants from five ongoing prospective birth cohort studies under the Japan Birth Cohort Consortium, two-stage individual-participant data meta-analyses were conducted to calculate risk ratios and PAFs for SGA in advanced maternal age, pre-pregnancy underweight, and smoking and alcohol consumption during pregnancy. Risk ratio was calculated using modified Poisson analyses with robust variance and PAF was calculated in each cohort, following common analyses protocols. Then, results from each cohort study were combined by meta-analyses using random-effects models to obtain the overall estimate for the Japanese population. In this meta-analysis, an increased risk (risk ratio, [95% confidence interval of SGA]) was significantly associated with pre-pregnancy underweight (1.72 [1.42-2.09]), gestational weight gain (1.95 [1.61-2.38]), and continued smoking during pregnancy (1.59 [1.01-2.50]). PAF of underweight, inadequate gestational weight gain, and continued smoking during pregnancy was 10.0% [4.6-15.1%], 31.4% [22.1-39.6%], and 3.2% [-4.8-10.5%], respectively. In conclusion, maternal weight status was a major contributor to SGA births in Japan. Improving maternal weight status should be prioritized to prevent fetal growth restriction.

Risk factors for non-previa placenta accreta spectrum in pregnancies conceived through frozen embryo transfer during a hormone replacement cycle in Japan

Purpose

Non-previa placenta accreta spectrum (PAS) is associated with assisted reproductive technology (ART), particularly frozen embryo transfer during hormone replacement therapy (HRC-FET). We especially aimed to evaluate the prevalence and risk factors for non-previa PAS in HRC-FET pregnancies.

Methods

Overall, 279 women who conceived through ART at three ART facilities and delivered at a single center were included in this retrospective study. Data regarding endometrial thickness at embryo transfer, previous histories, and type of embryo transfer-HRC-FET, frozen embryo transfer during a natural ovulatory cycle (NC-FET), and fresh embryo transfer (Fresh-ET)-were collected. Univariable logistic regression analyses were conducted.

Results

The prevalence of non-previa PAS was 27/192 (14.1%) in the HRC-FET group and 0 (0.0%) in both the NC-FET and Fresh-ET groups. Significantly high odds ratio [95% confidence interval] of non-previa PAS was associated with a history of artificial abortion (6.45 [1.98-21.02]), endometrial thickness <8.0 mm (6.11 [1.06-35.12]), resolved low-lying placenta (5.73 [2.13-15.41]), multiparity (2.90 [1.26-6.69]), polycystic ovarian syndrome (2.62 [1.02-6.71]), and subchorionic hematoma (2.49 [1.03-6.04]).

Conclusions

A history of artificial abortion, endometrial thickness <8.0 mm, and resolved low-lying placenta may help in antenatal detection of a high-risk population of non-previa PAS in HRC-FET pregnancies.

Cerebellar injury in preterm infants less than 28 weeks gestational age

BACKGROUND

Cerebellar injury is one of the perinatal complications in preterm infants. Recent studies have highlighted the effect of perinatal complications on neurological morbidity. We investigated the perinatal risk factors and morbidity for cerebellar injury in extremely premature infants.

METHODS

This retrospective cohort study included 285 infants born between April 2009 and December 2020 at gestational age <28 weeks at our institution. The infants were divided into two groups based on magnetic resonance imaging findings: those with and without cerebellar injury. We performed a statistical analysis of the perinatal background and short-term morbidity of the two groups.

RESULTS

Significant differences (p < 0.05) were observed between the groups with respect to the perinatal background, especially gestational weeks, birthweight, and hemoglobin values at birth. In the short-term morbidity, significant differences (p < 0.05) were observed in the incidence of respiratory distress syndrome, chronic lung disease, hydrocephalus, severe intraventricular hemorrhage (IVH), and cerebellar hemorrhage. Extensive cerebellar lesions, such as cerebellar agenesis or global cerebellar hypoplasia, accounted for 11 of the 22 cases of cerebellar injury; seven of the 11 cases had severe IVH in addition to cerebellar hemorrhage.

CONCLUSIONS

Gestational age was significantly lower in the cerebellar injury group. The combination of severe IVH and cerebellar hemorrhage may promote cerebellar injury.

Sex-specific differences in head circumference of term singletons after assisted reproductive technology: a multicentre study in Japan

RESEARCH QUESTION

Does fertility treatment, specifically assisted reproductive technology (ART), affect head circumference in term singletons?

DESIGN

A total of 32,651 women who delivered at term at 12 maternity hospitals in Japan between 2010 and 2018 were included in the analysis; of these, 1941 (5.9%) and 2984 (9.1%) women conceived through ART and non-ART fertility treatments (timed intercourse, ovulation induction or artificial insemination), respectively. The study evaluated the adjusted odds ratios of head circumference ≥90th percentile stratified by infant sex and type of ART procedure after adjusting for covariates, with natural conception as the reference group.

RESULTS

ART significantly increased the risk of head circumference ≥90th percentile (adjusted odds ratio 1.56 [95% confidence interval 1.25-1.96]), whereas non-ART fertility treatment did not increase the risk (1.14 [0.92-1.42]). This increased risk of head circumference ≥90th percentile was observed exclusively in male neonates (1.73 [1.33-2.26]) and not in female neonates (1.18 [0.76-1.85]) in the ART group. Frozen embryo transfer (FET), FET in a hormone replacement cycle (HRC-FET) and blastocyst-stage embryo transfer were significantly associated with head circumference ≥90th percentile (1.60 [1.26-2.02], 1.70 [1.30-2.22] and 1.72 [1.33-2.24], respectively).

CONCLUSIONS

The use of ART, particularly FET, HRC-FET or blastocyst-stage embryo transfer, was linked with a heightened risk of head circumference ≥90th percentile compared with non-ART fertility treatment or natural conception. The increased risk was observed only in male neonates.

New-onset postpartum hypertension in women without a history of hypertensive disorders of pregnancy: a multicenter study in Japan

The aim of this study was to investigate the prevalence and risk factors of new-onset postpartum hypertension (PPHTN), defined as new-onset hypertension during the postpartum period, among women without a history of hypertension during pregnancy and labor. A multicenter retrospective study was conducted using clinical data of women who delivered at term between 2011 and 2018 at 12 maternity hospitals. A total of 18,295 normotensive women were eligible, after excluding those with hypertensive disorders of pregnancy or hypertension during labor. New-onset PPHTN was defined as multiple blood pressure readings of ≥ 140/90 mmHg between 1 d and 4 weeks postpartum among normotensive women throughout pregnancy. Multivariate regression analyses were performed to evaluate the risk factors for new-onset PPHTN. Among the 18,295 normotensive women, 227 (1.2%) presented with new-onset PPHTN. The prevalence was higher in women who delivered via cesarean section than in those who delivered vaginally (7.0% and 1.0%, respectively). The independent risk factors were maternal age ≥ 35 years (adjusted odds ratio 1.67, 95% confidence interval [1.10-2.53]), nulliparity (1.83 [1.24-2.71]), high normal blood pressure (systolic blood pressure [SBP] 120-129 and diastolic blood pressure [DBP] < 80) at the last prenatal check-up (1.96 [1.23-3.13]), elevated blood pressure (SBP 130-139 and/or DBP 80-89) (6.42 [4.15-9.95]), urinary protein 1+ (1.99 [1.27-3.11]), scheduled cesarean section (4.05 [1.69-9.69]), and emergency cesarean section (10.02 [5.10-19.70]). New-onset PPHTN was observed in 1.2% of the normotensive women, with women who delivered via cesarean section having the highest risk. Close postpartum blood pressure monitoring may be required for women with multiple risk factors to identify new-onset PPHTN in a timely manner and reduce adverse maternal consequences.

Antenatal corticosteroids and outcomes of small for gestational age infants born at 24-31 gestational weeks: a population-based propensity score matching analysis

PURPOSE

To evaluate the effect of antenatal corticosteroid (ACS) treatment on neonatal outcomes in small for gestational age (SGA) infants born at 24-31 gestational weeks compared with non-SGA infants.

METHODS

A population-based retrospective study was conducted that analyzed clinical data from the Neonatal Research Network of Japan database, which enrolls neonates born at < 32 gestational weeks and weighing 1500 g or less (n = 22,414). Propensity score matching (with the ratio of ACS to no-ACS groups of 1:1) was performed in SGA (n = 7028) and non-SGA (n = 15,386) infants, respectively. Univariate logistic and interaction analyses were performed to compare the short-term neonatal outcomes of infants with and without ACS treatment in utero.

RESULTS

In the SGA and non-SGA infants, ACS treatment significantly reduced in-hospital mortality (odds ratio 0.67 95% confidence interval [0.50-0.88] and 0.62 [0.50-0.78], respectively), respiratory distress syndrome (0.77 [0.69-0.87] and 0.63 [0.58-0.68], respectively), and composite adverse outcomes (0.73 [0.58-0.91] and 0.57 [0.50-0.65], respectively). ACS treatment also significantly reduced intraventricular hemorrhage (grade III/IV), periventricular leukomalacia, and sepsis in the non-SGA infants, but not in the SGA infants. However, interaction analyses revealed no significant differences between the SGA and non-SGA infants in the efficacy of ACS treatment on short-term outcomes except for respiratory distress syndrome.

CONCLUSIONS

ACS treatment was associated with beneficial effects on mortality, respiratory distress syndrome, and adverse composite outcomes in extremely and very preterm SGA infants, with similar efficacy on all neonatal outcomes except for respiratory distress syndrome observed in the non-SGA infants.

Difference in risk of preterm and small-for-gestational-age birth depending on maternal occupations in Japan

OBJECTIVES

In this study, an association between the mother's occupations with preterm and small-for-gestational-age (SGA) births was investigated using national data in Japan, and individual-level birth data from the Report of Vital Statistics: Occupational and Industrial Aspects in the 2015 fiscal year were used. Preterm and SGA birth rates were calculated for each of infant characteristics, and relative risk of each type of maternal occupations (categorized into 12 types) for the outcomes was estimated using a log binomial regression model.

RESULTS

Data of 997,600 singleton births were analyzed. Among maternal occupations, preterm birth rate was highest among carrying, cleaning, packaging, and related workers (5.65%) and lowest among security workers (4.24%). SGA birth rate was highest among manufacturing process workers (5.91%) and lowest among security workers (4.00%). We found significantly elevated risks for preterm birth among manufacturing process workers compared with unemployed mothers, and significantly elevated risks for SGA birth compared with unemployed mothers were observed among sales workers, service workers, and manufacturing process workers. In contrast, security workers had a significantly decreased risk for SGA birth compared with unemployed mothers.

Cord blood triglyceride and total cholesterol in preterm and term neonates: reference values and associated factors from the Japan Environment and Children's Study

This study aimed to investigate the associations between cord serum total cholesterol (TC) and triglyceride (TG)levels and perinatal factors and determine the reference levels of cord blood TC and TG in Japanese neonates. This was a prospective birth cohort study using data from the Japan Environment and Children's Study, which included data on births from 2011 to 2014 in Japan. TC and TG levels were determined in cord blood samples. A total of 70,535 pairs of neonates (male: 36,001, female: 34,524) and mothers were included. The mean cord blood TC and TG levels were 72.2 mg/dL and 24.4 mg/dL, respectively. Multiple regression analyses revealed that gestational age and birth weight were significantly associated with cord blood TC (coefficient -2.35, 95% confidence interval [CI] -2.40 - -2.22 and coefficient 0.002, 95% CI 0.002-0.003, respectively) and TG (coefficient 3.09, 95% CI 3.01-3.17 and coefficient - 0.009, 95% CI - 0.009-0.008, respectively) levels. Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories.    Conclusion: Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories in Japanese newborns. Maternal complications such as maternal parity, HDP, PROM, maternal obesity and income level were associated with cord TC and TG levels. What is Known: • No studies have ascertained the reference levels of cord blood lipid levels in Japan. What is New: • Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term.

Factors associated with low birthweight among late preterm singletons in Japan using pregnancy birth registry data

Late preterm (LP, born between 34 0/7 and 36 6/7 weeks of gestation) infants may experience several adverse outcomes, similar to those experienced by low birthweight (LBW, birthweight <2500 g) infants. However, while LP infants are often born with LBW, the association between LP and LBW remains unknown. This study aimed to investigate LBW rate and independent risk factors for LBW in LP singleton neonates. We retrospectively analyzed data of LP singleton neonates, born between 2013 and 2017, from the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System. The exclusion criteria included stillbirths and infants with missing data. Logistic regression analyses were performed to investigate maternal and perinatal factors associated with LBW in LP singletons. LBW was observed in 62.5% (n = 35,113) of 56,160 LP singleton births. In the multiple logistic regression analysis, LBW in LP neonates was independently associated with modifiable maternal factors, including pre-pregnancy underweight, inadequate gestational weight gain, and smoking during pregnancy, as well as non-modifiable factors, including younger maternal age, nulliparity, hypertensive disorder of pregnancy, preeclampsia, cesarean section delivery, and female offspring. According to the Japanese pregnancy birth registry data, more than half of LP neonates were LBW. We previously discussed the issue of LBW regarding infants with different backgrounds, as there are many different causes of LBW. Several risk factors should be subdivided and considered for the risk of LP and LBW.

Delivery room intubation and severe intraventricular hemorrhage in extremely preterm infants without low Apgar scores: A Japanese retrospective cohort study

The purpose of this study was to assess the associations between delivery room intubation (DRI) and severe intraventricular hemorrhage (IVH), as well as other neonatal outcomes, among extremely preterm infants without low Apgar scores using data from a large-scale neonatal registry data in Japan. We analyzed data for infants born at 24-27 gestational weeks between 2003 and 2019 in Japan using robust Poisson regression. Infants with low Apgar scores (≤ 1 at 1 min or ≤ 3 at 5 min) were excluded. The primary outcome was severe IVH. Secondary outcomes were other neonatal morbidities and mortality. The full cohort included 16,081 infants (intubation cohort, 13,367; no intubation cohort, 2714). The rate of DRI increased over time (78.6%, 2003-2008; 83.4%, 2009-2014; 87.8%, 2015-2019), while the rate of severe IVH decreased (7.1%, 2003-2008; 5.7%, 2009-2014; 5.3%, 2015-2019). Infants with DRI had a higher risk of severe IVH than those without DRI (6.8% vs. 2.3%; adjusted risk ratio, 1.86; 95% confidence interval, 1.33-2.58). The results did not change substantially when stratified by gestational age. Despite conflicting changes over time in DRI and severe IVH, DRI was associated with an increased risk of severe IVH among extremely preterm infants in Japan.

The Associated Factors of Low Birthweight Among Term Singletons in Japan: A Pregnancy Birth Registry Analysis

BACKGROUND

Progress in reducing the global low birthweight (LBW) has been insufficient. Although the focus has been on preventing preterm birth, evidence regarding LBW in term births is limited. Despite its low preterm birth prevalence, Japan has a higher LBW proportion than other developed countries. This study aimed to examine the prevalence of LBW in term singleton births and its associated factors using a national database.

METHODS

We retrospectively analyzed the data of neonates registered in the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System who were born 2013-2017. Exclusion criteria included stillbirths, delivery after 42 gestational weeks, and missing data. Logistic regression analyses were performed to investigate the maternal and perinatal factors associated with LBW in term singletons using the data of 715,414 singleton neonates.

RESULTS

The overall prevalence of LBW was 18.3%, and 35.7% of LBWs originated from singleton term pregnancies. Multiple logistic regression analyses indicated that both modifiable and non-modifiable factors were independently associated with LBW in term neonates. The modifiable maternal factors included pre-pregnancy underweight, inadequate gestational weight gain, and smoking during pregnancy, while the non-modifiable factors included younger maternal age, nulliparity, hypertensive disorders of pregnancy, cesarean section delivery, female offspring, and congenital anomalies.

CONCLUSION

Using the Japanese pregnancy birth registry data, more than one-third of LBWs were found to originate from singleton term pregnancies. Both modifiable and non-modifiable factors were independently associated with LBW in term neonates. Prevention strategies on modifiable risk factor control will be effective in reducing LBW worldwide.

The Association between Early Gram-Negative Bacteria in Tracheal Aspirate Cultures and Severe Bronchopulmonary Dysplasia among Extremely Preterm Infants Requiring Prolonged Ventilation

OBJECTIVE

The study aimed to evaluate the association between bronchopulmonary dysplasia (BPD) development at 36 weeks' postmenstrual age (PMA) and Gram-negative bacteria in tracheal aspirate cultures among extremely preterm infants.

STUDY DESIGN

This study has a retrospective cohort. Patients were 155 infants aged less than or equal to 26 gestational weeks who were admitted to the neonatal intensive care unit of Osaka Women's and Children's Hospital from 2009 to 2018. Primary outcome was respiratory outcomes expressed as BPD development.Multivariable logistic regression analysis was used to identify neonatal and bacterial factors associated with BPD.

RESULTS

After adjusting for gestational age, birth weight, sex, chorioamnionitis, Gram-positive cocci (GPC) and Gram-negative rods (GNRs) in tracheal aspirate cultures within 28 days after birth, GNRs were significantly associated with BPD development (odds ratio [OR]: 3.88, 95% confidence interval [CI]: 1.68-8.94). In contrast, GPCs were not associated with BPD development (OR: 0.47, 95% CI: 0.05-1.61).

CONCLUSION

Gram-negative bacteria in tracheal cultures within 28 days of birth are associated with BPD development in infants aged less than or equal to 26 gestational weeks.

KEY POINTS

· BPD is a factor for morbidity in extremely preterm infants.. · Respiratory infection is an adverse outcome of BPD.. · GNRs in tracheal cultures soon after birth disturb BPD development.. · GPC was not associated with BPD development..

Association between gestational age at threatened preterm birth diagnosis and incidence of preterm birth: the Japan Environment and Children's Study

We evaluated the association between gestational age at threatened preterm birth (TPTB) diagnosis and preterm birth (PTB) incidence using a nationwide birth cohort. Data of 94,236 women with singleton deliveries from the Japan Environment and Children's Study (enrolled between 2011 and 2014) were analysed. Participants were divided based on parity and gestational age at TPTB diagnosis (22-24, 25-27, 28-30, 31-33, and 34-36 weeks). Multivariable logistic regression models were used to calculate the odds ratios (ORs) for PTB before 37 and 34 weeks in women from all groups, using participants without TPTB as the reference. The adjusted ORs for PTB before 37 weeks were the highest in the latest gestational age group in nulliparous and multiparous women without previous PTB, while those before 34 weeks were the highest in the earliest and latest gestational age group in multiparous women without previous PTB and in the earliest gestational age group in multiparous women with previous PTB. The association between gestational age at TPTB diagnosis and PTB incidence varies based on maternal parity and PTB before 37 or 34 weeks. Further studies with detailed clinical data and a unified TPTB diagnosis protocol are necessary to clarify this association.

Sleep quality and temperament in association with autism spectrum disorder among infants in Japan

BACKGROUND

Sleep problems and irritable temperaments are common among infants with autism spectrum disorder (ASD). The prospective association between such sleep problems and irritable temperaments and ASDs needs to be determined for elucidating the mechanism and exploring the future intervention study. Thus, in this study, we investigated whether sleep quality and temperament in 1-month-old infants are associated with the onset of ASD in 3-year-old children. We also assessed its sex-stratified associations.

METHODS

We conducted a longitudinal study using data from 69,751 mothers and infants from a large-cohort study, the Japan Environment and Children's Study. We examined the prospective association between infant sleep quality and temperament at 1 month of age and ASD diagnosis by 3 years of age.

RESULTS

Here we show infants with longer daytime sleep have a higher risk of later ASD than those with shorter daytime sleep (risk ratio [RR]: 1.33, 95% confidence interval [CI]: 1.01-1.75). Infants who experienced intense crying have a higher risk of ASD than those who did not (RR: 1.31, 95% CI: 1.00-1.72). There is a difference in sex in the association between a bad mood and later ASD. In particular, female infants experiencing bad moods have a higher risk of ASD than others (RR: 3.59, 95% CI: 1.91-6.75).

CONCLUSIONS

The study findings provide important information for future intervention to reduce the risk of future ASD.

Evaluating glucose variability through OGTT in early pregnancy and its association with hypertensive disorders of pregnancy in non-diabetic pregnancies: a large-scale multi-center retrospective study

BACKGROUND

Recent evidence suggests increased glucose variability (GV) causes endothelial dysfunction, a central pathology of hypertensive disorders of pregnancy (HDP). We aimed to investigate the association between GV in early pregnancy and subsequent HDP development among non-diabetes mellitus (DM) pregnancies.

METHODS

This multicenter retrospective study used data from singleton pregnancies between 2009 and 2019. Among individuals who had 75 g-OGTT before 20 weeks of gestation, we evaluated GV by 75 g-OGTT parameters and examined its relationship with HDP development, defining an initial-increase from fasting-plasma glucose (PG) to 1-h-PG and subsequent-decrease from 1-h-PG to 2-h-PG.

RESULTS

Approximately 3.0% pregnancies (802/26,995) had 75 g-OGTT before 20 weeks of gestation, and they had a higher prevalence of HDP (14.3% vs. 7.5%). The initial-increase was significantly associated with overall HDP (aOR 1.20, 95% CI 1.02-1.42), and the subsequent-decrease was associated with decreased and increased development of early-onset (EoHDP: aOR 0.56, 95% CI 0.38-0.82) and late-onset HDP (LoHDP: aOR 1.38, 95% CI 1.11-1.73), respectively.

CONCLUSIONS

A pattern of marked initial-increase and minor subsequent-decrease (i.e., sustained hyperglycemia) was associated with EoHDP. Contrarily, the pattern of marked initial-increase and subsequent-decrease (i.e., increased GV) was associated with LoHDP. This provides a new perspective for future study strategies.

Influence of chest/head circumference ratio at birth on obstetric and neonatal outcomes: The Japan environment and children's study

OBJECTIVES

Some newborns that are not small-for-gestational-age (non-SGA, birthweight ≥10th percentile for a given gestational age) may have pathologic growth restrictions. This study examined the association of adverse obstetric and neonatal outcomes with chest/head circumference ratio at birth in non-SGA and SGA newborns.

METHODS

This study was a cross-sectional evaluation of data from a nationwide prospective birth cohort study, the Japan Environment and Children's Study. We analyzed 93 690 non-anomalous singletons born at 34-41 gestational weeks. We defined low, normal, and high chest/head circumference ratio as <10th percentile, 10th-90th percentile, and >90th percentile, respectively, according to the internally constructed chest/head circumference percentile chart. Modified Poisson regression was used to estimate adjusted prevalence ratios (aPR) for the outcomes studied.

RESULTS

Compared with non-SGA newborns with a normal ratio, those with a low ratio had an increased occurrence of low birthweight (1.75, 1.58-1.94 [aPR, 95% confidence interval]), cesarean delivery (1.34, 1.29-1.38), Apgar score <7 at 5 min (1.57, 1.14-2.17), respiratory complications (1.20, 1.04-1.39), and prolonged hospitalization (1.36, 1.30-1.42). In contrast, the high-ratio group had a lower rate of low birthweight (0.71, 0.59-0.86), cesarean delivery (0.82, 0.77-0.87), and prolonged hospitalization (0.83, 0.78-0.89). In SGA newborns, a low ratio was associated with increased aPRs for low birthweight, cesarean delivery, hypoglycemia, and prolonged hospitalization, whereas a high ratio showed no such association.

CONCLUSIONS

Findings indicate that the chest/head circumference ratio at birth influence obstetric and neonatal outcomes regardless of the birthweight status.

Achievement of Target Glycemic Goal with Simple Basal Insulin Regimen in Women with Gestational Diabetes: A Prospective Cohort Study

There is little evidence concerning the need to treat gestational diabetes (GDM) in the same way as pregestational diabetes. We evaluated the efficacy of the simple insulin injection (SII) regimen for achieving the target glucose goal without increasing adverse perinatal outcomes in singleton pregnant women with GDM. All subjects underwent self-monitoring of blood glucose (SMBG), and insulin therapy was indicated according to the SMBG profile. Insulin was initially started with the SII regimen, in which one daily injection of NPH insulin before breakfast was used, and another NPH injection was added at bedtime, if necessary. We used the target glucose as <95 mg/dL at fasting and <120 mg/dL postprandial and accepted <130 mg/dL for the latter. If the target glucose did not reach with the regimen, we switched to the multiple daily injection (MDI) with additional prandial insulin aspart. We compared the SMBG profile before delivery as well as the perinatal outcomes between the SII and MDI groups. Among 361 women (age 33.7 years, nullipara 41%, prepregnancy body mass index 23.2 kg/m²) with GDM, 59%, 18%, and 23% were in the diet-alone, SII, and MDI groups, respectively. Consequently, regarding women requiring insulin therapy, 43% were treated with the SII regimen throughout pregnancy. The severity of baseline hyperglycemia according to the SMBG data at baseline was the MDI>the SII>the diet group. The rate of achieving target glucose levels before delivery in the SII group at fasting, postprandial < 120 mg/dL and <130 mg/dL were 93%, 54% and 87%, respectively, which were similar to that in the MDI group (93%, 57%, and 93%, respectively), with no significant differences in perinatal outcomes. In conclusion, more than 40% of women with GDM requiring insulin therapy achieved the target glucose goal with this simple insulin regimen without any increase in adverse effects.

Association of Maternal Asthma and Total Serum Immunoglobulin E levels with Obstetric Complications: The Japan Environment and Children's Study

OBJECTIVE

To evaluate the association between maternal asthma (MA) and obstetric complications, while considering subdivided total serum immunoglobulin E (IgE) levels.

METHODS

Data of the participants enrolled in the Japan Environment and Children's Study between 2011 and 2014 were analyzed. In total, 77,131 women with singleton live births at and after 22 weeks of gestation were included. MA was defined based on a self-administered questionnaire. Women with MA were stratified based on the quartile of total serum IgE levels during pregnancy as follows: low IgE levels (< 52.40 IU/mL), moderate IgE levels (52.40-331.00 IU/mL), and high IgE levels (> 331.00 IU/mL). The adjusted odds ratios (aORs) for preterm births (PTB), small for gestational age (SGA) infants, gestational diabetes mellitus, and hypertensive disorders of pregnancy (HDP) were calculated using multivariable logistic regression, while considering women without MA as reference and maternal socioeconomic factors as confounders.

RESULTS

The aORs for SGA infants and HDP in women with MA and high total serum IgE levels were 1.26 (95% confidence interval [CI], 1.05-1.50) and 1.33 (95% CI, 1.06-1.66), respectively. The aOR for SGA infants among women with MA and moderate total serum IgE levels was 0.85 (95% CI, 0.73-0.99). The aOR for PTB among women with MA and low total serum IgE levels was 1.26 (95% CI, 1.04-1.52).

CONCLUSIONS FOR PRACTICE

MA with subdivided total serum IgE levels was associated with obstetric complications. Total serum IgE level may be a potential prognostic marker to predict obstetric complications in pregnancies with MA.

Maternal triglyceride levels and neonatal outcomes: The Japan Environment and Children's Study

BACKGROUND

Although maternal triglyceride (TG) is important for fetal growth, there are few large cohort studies investigating the relationships between maternal TG during pregnancy and neonatal outcomes.

OBJECTIVES

The objective of this study was to investigate the associations between maternal TG during the second and third trimesters and neonatal outcomes including preterm birth (PTB), low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA).

METHODS

This was a prospective birth cohort study using data of the Japan Environment and Children's Study included data of births from 2011-2014 in Japan including 79,519 pairs. Participants were divided into tertiles according to maternal TG in the second or third trimesters. Multiple logistic regression modeling was used to examine the risks of LBW, SGA, LGA and PTB in association with maternal TG levels in the second or third trimesters RESULTS: In the second trimester, compared with reference TG group (T2), women in higher TG group (T3) and lower TG group (T1) were also at increased risk of LGA (aOR 1.20, 95% CI 1.11-1.29) and SGA (aOR 1.25, 95% CI 1.10-1.41), respectively. In the third trimester, women in T3 and T1 were at increased risk of LGA (aOR 1.27, 95% CI 1.17-1.38) and SGA (aOR 1.17, 95% CI 1.02-1.34), respectively.

CONCLUSION

In this study, higher maternal TG levels in the second or third trimesters were associated with risks of LGA, however, lower maternal TG levels in the second or third trimesters were conversely associated with risks of SGA.

Diet Quality and Its Relationship with Weight Characteristics in Pregnant Japanese Women: A Single-Center Birth Cohort Study

Maternal underweight and inadequate gestational weight gain (GWG) are problems in Japan. However, increases in food intake aimed at weight gain alone are not sufficient for mother-child health. This study assessed diet quality based on the 3-day dietary records of pregnant women in an urban area of Japan in order to show the importance of evaluating diet quality, using the Nutrient-Rich Food Index 9.3 (NRF9.3), which is one metric based on nutrition profiling, and the Japanese Food Guide Spinning Top (JFGST). After excluding misreporters of energy intake, we stratified women (n = 91) by pre-pregnancy body mass index (BMI) and determined energy intake, diet quality status, and their relationship with GWG. Intakes of carbohydrate-containing staple foods, vegetable dishes, and fruit were insufficient regardless of BMI. Most of the underweight women with inadequate GWG had insufficient energy intake but high diet quality, as assessed by NRF9.3. In contrast, most women who consumed energy within the recommended range had low diet quality and gained weight at inappropriate levels. These results highlight the importance for pregnant Japanese women to maintain diet quality through a nutrient-dense diet, while simultaneously increasing energy intake after evaluation of their individual diet quality.

Changes in In-Hospital Survival and Long-Term Neurodevelopmental Outcomes of Extremely Preterm Infants: A Retrospective Study of a Japanese Tertiary Center

OBJECTIVES

The objective of this study was to elucidate whether the survival and long-term neurodevelopmental outcomes of extremely preterm infants have improved in a Japanese tertiary center with an active treatment policy for infants born at 22-23 weeks of gestation.

STUDY DESIGN

This single-centered retrospective cohort study enrolled extremely preterm infants treated at Saitama Medical Center, Saitama Medical University, from 2003 to 2014. Patients with major congenital abnormalities were excluded. Primary outcomes were in-hospital survival and severe neurodevelopmental impairment (NDI) at 6 years of age, which was defined as having severe cerebral palsy, severe cognitive impairment, severe visual impairment, or deafness. We assessed the changes in primary outcomes between the first (period 1; 2003-2008) and the second half (period 2; 2009-2014) of the study period and evaluated the association between birth-year and primary outcomes using multivariate logistic regression models.

RESULTS

Of the 403 eligible patients, 340 (84%) survived to discharge. Among 248 patients available at 6 years of age, 43 (14%) were classified as having severe NDI. Between the 2 periods, in-hospital survival improved from 155 of 198 (78%) to 185 of 205 (90%), but severe NDI increased from 11 of 108 (10%) to 32 of 140 (23%). In multivariate logistic regression models adjusted for gestational age, birthweight, sex, singleton birth, and antenatal corticosteroids, the aOR (95% CI) of birth-year for in-hospital survival and severe NDI was 1.2 (1.1-1.3) and 1.1 (1.0-1.3), respectively.

CONCLUSION

Mortality among extremely preterm infants has improved over the past 12 years; nevertheless, no significant improvement was observed in the long-term neurodevelopmental outcomes.

Dosage of hydrocortisone during late infancy is positively associated with changes in body mass index during early childhood in patients with 21-hydroxylase deficiency

Obesity is a major complication in children with 21-hydroxylase deficiency (21-OHD). There is evidence to show that higher body mass index (BMI) during infancy and early childhood is associated with an increased risk for the subsequent development of obesity in the general population; however, limited information is currently available on this issue in 21-OHD patients. Additionally, despite the frequent use of supraphysiological dosages of hydrocortisone in 21-OHD, the association between BMI and hydrocortisone dosage during these periods remains largely unclear; therefore, we retrospectively investigated BMI at approximately 1 and 3 years old and its association with hydrocortisone dosage in 56 children with 21-OHD. The median BMI-standard deviation score (SDS) was 0.28 (Interquartile range [IQR]: -0.53 to 1.09) and 0.39 (IQR: -0.44 to 1.14) at approximately 1 and 3 years old, respectively, and no association was observed between hydrocortisone dosage and BMI-SDS at either time-point; however, multivariate analysis revealed that hydrocortisone dosage at approximately 1 year old was positively associated with changes in BMI (β = 0.57, p = 0.013) and BMI-SDS (β = 0.59, p = 0.011) between approximately 1 and 3 years old after adjustment for age, sex, and changes in hydrocortisone dosage during the same period. The average dosage of hydrocortisone between approximately 6 months and 1 year old also showed similar results. These results indicate that a higher dosage of hydrocortisone during late infancy is associated with a higher BMI at approximately 3 years old, which may lead to the development of obesity later in life in children with 21-OHD.

Relationship between Birth Order and Postnatal Growth until 4 Years of Age: The Japan Environment and Children’s Study

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 26,249 full-term singleton births were targeted. General linear and multivariable logistic regression models were performed and adjusted for birth weight, parents’ heights, maternal age at delivery, gestational weight gain, maternal smoking and alcohol drinking status during pregnancy, household income, breastfeeding status, and Study Areas. The multivariate adjusted mean length Z-scores in “first-borns having no sibling”, “first-borns having siblings”, “second-borns”, and “third-borns or more” were −0.026, −0.013, 0.136, and 0.120 at birth and −0.324, −0.330, −0.466, and −0.569 at 10 months, respectively. Results similar to those at 10 months were observed at 1.5, 3, and 4 years. The adjusted odds ratios (95% confidence intervals) of short stature at 4 years in “first-borns having siblings”, “second-borns”, and “third-borns or more” were 1.08 (0.84–1.39), 1.36 (1.13–1.62), and 1.50 (1.20–1.88), respectively, versus “first-borns having no sibling”. Birth order was significantly associated with postnatal growth and may be a factor predisposing to short stature in early childhood.

Prospective cohort study for postnatal cytomegalovirus infection in preterm infants

AIM

Cytomegalovirus (CMV) is a virus that can cause congenital and postnatal infections. Postnatal CMV is mainly transmitted via breast milk and blood transfusions. Frozen-thawed breast milk is used to prevent postnatal CMV infection. A prospective cohort study was conducted to determine the infection rate, risk, and clinical findings of postnatal CMV infection.

METHODS

This prospective cohort study included infants born at 32 weeks or earlier than the gestational age (GA). Participants were prospectively screened for infection in the urine by performing urine CMV DNA tests twice, that is, once within the first 3 weeks of life and again after 35 weeks postmenstrual age (PMA). Postnatal CMV infection was defined as a case of CMV negative tests within 3 weeks of birth and CMV positive tests after 35 weeks PMA. CMV-negative blood products were used for transfusions in all cases.

RESULTS

A total of 139 patients were subjected to two urine CMV DNA tests. The prevalence of postnatal CMV infection was 5.0%. One patient died of sepsis-like syndrome. The risk factors of postnatal CMV infection were younger GA and older age of the mother. The characteristic clinical findings of postnatal CMV infection were pneumonia.

CONCLUSIONS

Frozen-thawed breast milk feeding is not fully effective in preventing postnatal CMV infection. The prevention of postnatal CMV infection is important to further improve the survival rate of preterm infants. Development of guidelines on breast milk feeding for the prevention of postnatal CMV infection is necessary in Japan.

Dental radiographic information of term newborn babies within the first month: Analyzing five radiographic cases along with physical attributes in Japan

BACKGROUND

Although dental radiography is a valuable tool for age estimation in forensic anthropology and odontology, very limited radiological data are available regarding tooth development in healthy newborn babies during the first month of life.

AIM

This study aimed to describe the radiological findings of tooth development in babies aged 0 days to 1 month.

DESIGN

We analyzed the postmortem findings of five newborn babies with no known natural cause of death who had undergone autopsy, computed tomography (CT), and dental radiography. We estimated the gestational age for the babies aged 0 days and analyzed the condition of mandibular symphysis, existence of tooth germs, and presence or absence of calcification of the first permanent molars of all the babies.

RESULTS

The calcified form of 20 deciduous teeth, tooth germs of the permanent upper and lower first molars, and non-calcified mandibular symphysis were observed in each case. However, calcification of the first permanent molar was observed in only two 1-month-old babies.

CONCLUSION

The dental radiographic findings and anthropometric measurements of non-skeletonized, non-mummified term babies confirmed calcification of all the deciduous teeth and the first permanent molar at the age of 0 days and 1 month, respectively.

Mild small-for-gestational-age as a non-negligible risk factor for short stature

Risk of subsequent short stature remains unclear among mild small-for-gestational-age (SGA) infants with birthweight <10th percentile and ≥-2 standard deviations. In this multicenter cohort study in Japan, height was found to be <-2 standard deviations at 3 years old even in 18 % of mild-SGA infants.

Dexmedetomidine versus fentanyl for sedation in extremely preterm infants

BACKGROUND

Few studies have compared the efficacy and complications of dexmedetomidine (DEX) and fentanyl (FEN) in extremely preterm infants.

METHODS

We conducted a single-institution, retrospective controlled before and after study of preterm infants before 28 weeks of gestation admitted between April 2010 and December 2018 to compare the complications and efficacy of DEX and FEN for preterm infants. Patients were administered FEN prior to 2015 and DEX after 2015 as the first-line sedative. A composite outcome of death during hospitalization and developmental quotient (DQ) < 70 at a corrected age of 3 years was compared as the primary outcome. Secondary outcomes including postmenstrual weeks at extubation, days of age when full enteral feeding was achieved and additional sedation by phenobarbital (PB) were compared.

RESULTS

Sixty-six infants were enrolled into the study. The only perinatal factor that differed between the FEN (n = 33) and DEX (n = 33) groups was weeks of gestation. The composite outcome of death and DQ < 70 at a corrected age of 3 years were not significantly different. Postmenstrual weeks at extubation did not significantly differ between groups after adjustment for weeks of gestation and being small for gestational age. On the other hand, full feeding was significantly prolonged by DEX (p = 0.031). Additional sedation was less common in the DEX group (p = 0.044).

CONCLUSION

The composite outcome of death and DQ < 70 at a corrected age of 3 years were not significantly different by DEX or FEN for primary sedation. Prospective randomized controlled trials should examine the long-term effects on development.