Background
More than 10 years have passed since the previous Japanese neonatal growth charts were published, therefore the aim of this study was to develop an updated set of Japanese neonatal growth ...charts.
Methods
We used data from the registry database of the Japan Society of Obstetrics and Gynecology from 2003 until 2005. A total of 150 471 singleton live births without stillbirth or severe congenital malformation were enrolled in the preliminary analysis. It was found that the distribution of the 10th centile charts based on these subjects was skewed toward lower birthweight for preterm infants, because of the significantly lower birthweight in the 10th centile in neonates delivered by cesarean section than those delivered vaginally. Therefore, the data of subjects delivered by cesarean section were also excluded.
Results
Finally, 104 748 singleton vaginal births at 22–41 weeks of gestation were used to construct a new set of Japanese neonatal anthropometric charts. The birthweight chart is parity and sex specific. The differences between the Japanese fetal growth chart and the new neonatal birthweight chart were small.
Conclusion
The present new neonatal anthropometric charts may reveal unrestricted growth pattern mimicking fetal growth. Use of these charts may result in recognition of abnormal fetal growth and risk in preterm infants. Further studies are needed to evaluate the risk for adverse neonatal and long‐term outcome among small‐for‐gestational‐age infants using these neonatal charts.
The main mode of mother-to-child transmission of the human T-cell leukemia virus (HTLV)-1 is through breastfeeding. Although the most reliable nutritional regimen to prevent HTLV-1 transmission is ...exclusive formula feeding, a recent meta-analysis revealed that short-term breastfeeding within 90 days does not increase the risk of infection. The protocol of the Japanese Health, Labor, and Welfare Science Research Group primarily recommended exclusive formula feeding for mothers who are positive for HTLV-1. However, there has been no quantitative research on the difficulties experienced by HTLV-1-positive mothers in carrying out these nutritional regimens, including the psychological burden. Therefore, this review was performed to clarify the burdens and difficulties encountered by mothers who are positive for HTLV-1; to this end, we analyzed the data registrants on the HTLV-1 career registration website “Carri-net” website. The data strongly suggest that it is not sufficient to simply recommend exclusive formula feeding or short-term breastfeeding as a means of preventing mother-to-child transmission; it is important for health care providers to understand that these nutritional regimens represent a major burden for pregnant women who are positive for HTLV-1 and to provide close support to ensure these women’s health.
Approximately 95% of mother-to-child transmission (MTCT) of human T-cell leukemia virus type-1 (HTLV-1) is derived from prolonged breastfeeding, which is a major cause of adult T-cell leukemia (ATL). ...Exclusive formula feeding (ExFF) is therefore generally used to prevent MTCT. A recent cohort study revealed that 55% of pregnant carriers chose short-term breastfeeding for ≤3 months in Japan. Our meta-analysis showed that there was no significant increase in the risk of MTCT when breastfeeding was carried out for ≤3 months compared with ExFF (pooled relative risk (RR), 0.72; 95% confidence interval (CI), 0.30–1.77), but there was an almost threefold increase in risk when breastfeeding was carried out for up to 6 months (pooled RR, 2.91; 95% CI, 1.69–5.03). Thus, short-term breastfeeding for ≤3 months may be useful in preventing MTCT. Breastmilk is the best nutritional source for infants, and any approach to minimizing MTCT by avoiding or limiting breastfeeding must be balanced against the impact on the child’s health and mother–child bonding. To minimize the need for nutritional interventions, it is necessary to identify factors that predispose children born to carrier mothers to MTCT and thereby predict MTCT development with a high degree of accuracy.
The perception of human T-cell leukemia virus type 1 (HTlV-1) infection as a "silent disease" has recently given way to concern that its presence may be having a variety of effects. HTLV-1 is known ...to cause adult T-cell leukemia (ATL), an aggressive cancer of peripheral CD4 T cells; however, it is also responsible for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Most patients develop ATL as a result of HTLV-1 mother-to-child transmission. The primary route of mother-to-child transmission is through the mother's milk. In the absence of effective drug therapy, total artificial nutrition such as exclusive formula feeding is a reliable means of preventing mother-to-child transmission after birth, except for a small percentage of prenatal infections. A recent study found that the rate of mother-to-child transmission with short-term breastfeeding (within 90 days) did not exceed that of total artificial nutrition. Because these preventive measures are in exchange for the benefits of breastfeeding, clinical applications of antiretroviral drugs and immunotherapy with vaccines and neutralizing antibodies are urgently needed.
Japan has been running a nationwide antenatal human T-cell leukemia virus type-1 (HTLV-1) antibody screening program since 2010 for the prevention of HTLV-1 mother-to-child transmission. As part of ...the program, pregnant women are invited to take an HTLV-1 antibody screening test, usually within the first 30 weeks of gestation, during regular pregnancy checkups. Pregnant women tested positive on the antibody screening test undergo a confirmatory test, either western blotting or line immunoassay. In indeterminate case, polymerase chain reaction (PCR) is used as a final test to diagnose infection. Pregnant women tested positive on a confirmatory or PCR test are identified as HTLV-1 carriers. As breastfeeding is a predominant route of postnatal HTLV-1 mother-to-child transmission, exclusive formula feeding is widely used as a postnatal preventive measure. Although there is insufficient evidence that short-term breastfeeding during ≤3 months does not increase the risk of mother-to-child transmission compared to exclusive formula feeding, this feeding method is considered if the mother is eager to breastfeed her child. However, it is important that mothers and family members fully understand that there is an increase in the risk of mother-to-child transmission when breastfeeding would be prolonged. As there are only a few clinical studies on the protective effect of frozen-thawed breastmilk feeding on mother-to-child transmission of HTLV-1, there is little evidence to recommend this feeding method. Further study on the protective effects of these feeding methods are needed. It is assumed that the risk of anxiety or depression may increase in the mothers who selected exclusive formula feeding or short-term breastfeeding. Thus, an adequate support and counseling for these mothers should be provided. In addition to raising public awareness of HTLV-1 infection, epidemiological data from the nationwide program needs to be collected and analyzed. In most cases, infected children are asymptomatic, and it is necessary to clarify how these children should be followed medically.
Our goal was to investigate the neonatal mortality rate and the mortality rate during the NICU stay for extremely low birth weight infants born in Japan in 2005.
The Committee of Neonatal Medicine of ...the Japan Pediatric Society retrospectively surveyed the deaths of extremely low birth weight infants born and hospitalized between January 1 and December 31, 2005. From 297 institutions in Japan, data on 3065 extremely low birth weight infants, which represented 98.4% of those reported in the maternal and health statistics of Japan in 2005, were collected.
The neonatal mortality rate and the mortality rate during the NICU stay were 13.0% and 17.0%, respectively, which were lower than 17.7% and 21.5% in the survey in 2000. The neonatal mortality rates and the mortality rates during the NICU stay were 53.3% and 67.7% in the <400-g birth weight group (n = 62), 42.1% and 53.5% in the 400- to 499-g birth weight group (n = 159), 22.2% and 27.7% in the 500- to 599-g birth weight group (n = 387), 16.8% and 22.2% in the 600- to 699-g birth weight group (n = 537), 9.4% and 12.7% in the 700- to 799-g birth weight group (n = 574), 6.3% and 9.1% in the 800- to 899-g birth weight group (n = 649), and 3.9% and 5.3% in the 900- to 999-g birth weight group (n = 697), respectively. The factors involved in the deaths of extremely low birth weight infants included lower gestational age, lower birth weight, male gender, multiple birth, institutions in which <10 extremely low birth weight infants were admitted per year, and no prenatal maternal transfer.
The mortality rates of extremely low birth weight infants who were born in 2005 demonstrated definite improvement.
Background
Nationwide antenatal human T‐cell leukemia/lymphoma virus type‐1 (HTLV‐1) antibody screening has been conducted in Japan. The purpose of our study was to clarify the issues related to ...feeding options to prevent postnatal mother‐to‐child transmission.
Methods
Of the pregnant carriers at 92 facilities in Japan between 2012 and 2015, 735 were followed prospectively. Among the children born to them, 313 (42.6%) children were followed up to the age of 3 and tested for HTLV‐1 antibodies. The mother‐to‐child transmission rate was calculated for each feeding option selected before birth.
Results
Among the 313 pregnant carriers, 55.0, 35.1, 6.1, and 3.8% selected short‐term breast‐feeding (≤3 months), exclusive formula feeding, frozen‐thawed breast‐milk feeding, and longer‐term breast‐feeding, respectively. Despite short‐term breast‐feeding, 8–18% of the mothers continued breast‐feeding for 4–6 months. The mother‐to‐child transmission rate with short‐term breast‐feeding was 2.3% (4/172), and its risk ratio compared with that of exclusive formula feeding was not significantly different (0.365; 95% CI: 0.116–1.145). Because of the small number of children who were fed by frozen‐thawed breast‐milk, their mother‐to‐child transmission rate was not statistically reliable.
Conclusions
Pregnant HTLV‐1 carriers tended to select short‐term breast‐feeding in Japan. While short‐term breast‐feeding was not always easy to wean within 3 months, it may be a viable option for preventing postnatal mother‐to‐child transmission because the vertical transmission rate with short‐term breast‐feeding was not significantly higher than that with exclusive formula feeding. Increasing the follow‐up rates for children born to pregnant carriers may provide clearer evidence of preventative effects by short‐term breast‐feeding and frozen‐thawed breast‐milk feeding.
Background
If their own mother's milk (OMM) is not available, another mother's milk may be used for extremely low‐birthweight (ELBW) infants. Human milk is a bodily fluid, however, therefore we have ...assumed that other mother's milk is currently seldom given to infants despite its superiority to formula. Although the World Health Organization and the American Academy of Pediatrics have recommended using donor human milk (DHM) from a human milk bank (HMB) in the case that OMM is not available, there is no HMB in Japan. To assess whether other mother's milk is used for ELBW infants and whether an HMB is necessary in Japan, we surveyed neonatal intensive care units (NICU) via questionnaire.
Methods
The questionnaire was sent by email to members of the Japanese Neonatologist Association who are responsible for NICU.
Results
In total, 126 completed questionnaires (70.7%) were returned and analyzed. One‐fourth of NICU give other mother's milk to ELBW infants. The first choice of nutrition is OMM, but other mother's milk or formula is given to infants at 19% of NICU if OMM is unavailable. Approximately three‐fourths of NICU would like an HMB.
Conclusion
Although human milk contains contagious agents and authorities do not recommend giving other mother's milk as a substitute for OMM, other mother's milk is still a choice in NICU in Japan. Many neonatologists, however, would prefer a safer alternative, that is, DHM obtained from an accredited HMB. A well‐regulated HMB should be established and safe DHM should be available for all preterm infants if necessary.
Background: Globally, few published studies have tracked the temporal trend of dioxin levels in the human body since 2000. This study describes the annual trend of dioxin levels in human breast milk ...in Japanese mothers from 1998 through 2015. Methods: An observational study was conducted from 1998 through 2015. Participants were 1,194 healthy mothers following their first delivery who were recruited annually in Japan. Breast milk samples obtained from participants were analyzed using gas chromatography and mass spectrometry for dioxins, including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (PCBs). Results: Mean age was 29.5 years, and 53% of participants were 20–25 years old. A declining trend in total dioxin levels was found, from a peak of 20.8 pg toxic equivalence (TEQ)/g fat in 1998 to 7.2 pg TEQ/g fat in 2014. Data from the last 5 years of the study indicated a plateau at minimal levels. In contrast, an increasing trend was found in the mean age of participants during the last 5 years. Although significantly higher dioxin levels were observed in samples from older participants, an upward trend in dioxin levels was not observed, indicating that dietary and environmental exposure to dioxins had greatly diminished in recent years. Conclusions: Dioxin levels in human breast milk may be approaching a minimum in recent years in Japan. The findings may contribute to global reference levels for environmental pollution of dioxins, which remains a problem for many developing countries.