Trends in Birth Weight and the Incidence of Low Birth Weight and Advanced Maternal Age in Korea between 1993 and 2016

BACKGROUND: As the aging society progresses, the average age of mothers is also increasing. Advanced maternal age has been known to be associated with perinatal outcomes, as well as birth weight (BW). In this study, we aimed to investigate the perinatal factors associated with low birth weight infants (LBWIs) using birth statistics of the Korean population. METHODS: Birth statistics between 1993 and 2016 from the Korean Statistical Information Service were reviewed. We investigated 12,856,614 data points, which included the number of births, BWs, percentage of preterm births and LBWIs, multiple pregnancies, and maternal age. RESULTS: The proportion of LBWIs delivered by mothers of advanced maternal age has gradually increased since 1993. In addition, the proportion of older mothers (≥ 35 years old) giving birth to LBWIs has increased over the years. Average BW has a negative correlation with the ratio of preterm births, LBW, multiple births, and advanced maternal age. The mean BW also has a negative correlation with maternal age. CONCLUSION: This study shows that the average BW continues to decline, and the incidence of LBWIs is increasing in Korea since 1993. This study also revealed that several perinatal factors, including percentage of preterm births, LBWIs, multiple births, and maternal age influence the mean BW. Although this study did not investigate the effects of decreasing mean BW on perinatal health, future research is worth discussing.

Impact of Changes in Maternal Age and Parity Distribution on the Increasing Trends in the Low Birth Weight and Very Low Birth Weight Rates in South Korea, 2005-2015 / 예방의학회지

OBJECTIVES: The aim of this study was to evaluate the impact of shifts in maternal age and parity on the increasing trends in the low birth weight (LBW) and very low birth weight (VLBW) rates from 2005 to 2015 in South Korea. METHODS: Data from 4 993 041 live births registered with Statistics Korea during the period between 2005 and 2015 were analyzed. Applying a modified standardization method, we partitioned the total increment in the LBW and VLBW rates into (1) the increase in the LBW and VLBW rates due to changes in the maternal age and parity distribution (AP-dis) and (2) the increase due to changes in the age-specific and parity-specific rates (AP-spe) of LBW and VLBW for singleton and multiple births, respectively. RESULTS: During the study period, the total increment in the LBW and VLBW rates was 1.43%p and 0.25%p, respectively. Among singleton births, changes in the AP-dis accounted for 79% (0.34%p) and 50% (0.06%p) of the total increment in the LBW and VLBW rates, respectively. Meanwhile, among multiple births, changes in the AP-dis did not contribute to the increase in the LBW and VLBW rates, with 100% of the increase in the LBW (1.00%p) and VLBW (0.13%p) rates being attributed to changes in the AP-spe. CONCLUSIONS: This study demonstrated that shifts in maternal age and parity were prominent contributors to the increase in the LBW and VLBW rates among singleton births between 2005 and 2015 in South Korea.

Secular Trends of Multiple Birth Rate in Korea: 1981–2017

PURPOSE: To determine the secular trend of the multiple birth rate in Korea from 1981 to 2017. METHODS: This study used birth certificate data covering the years 1981–2017 (20,948,901 births), provided by Statistics Korea. The impact of assisted reproductive technologies (ART) on multiple birth was analyzed by examining data prior to and after the introduction of ART and the national support program for infertile couples in South Korea. The odds ratio (OR) and 95% confidence intervals were calculated to describe the secular trend in the multiple birth rate per 100 births. RESULTS: During this period, the multiple birth rate per 100 births increased by 277 percent from 1.031 to 3.891, the twin birth rate increased from 1.013 to 3.807 (275%), and the triplet birth rate increased from 0.018 to 0.084 (363%). The secular trend of the multiple birth rate remained in the 1.000 level during 1981–1991, but has been rising steadily since 1992. The average increment of the multiple birth rate was 3.9% annually from 1981 through 2017 (peaking at more than 10 percent during 2006–2007). Prior to the introduction of ART in Korea (1981–1984), the multiple birth rate was 1.007, but after its introduction, the multiple birth rate was 1.005 in 1985–1989 (OR, 0.998; 95% confidence interval, 0.982–1.014), 1.084 in 1990–1994 (1.007; 1.060–1.094), 1.891 in 2000–2004 (1.894; 1.866–1.922), 3.127 in 2010–2014 (3.173; 3.129–3.217), and 3.811 in 2015–2017 (3.893; 3.835–3.952). CONCLUSION: Over the past three decades, multiple births have risen dramatically in Korea, primarily due to the increasingly widespread use of fertility therapies, and the delayed age of childbearing. There is a need for more research to understand the factors contributing to multiple births, and the national birth registration systems ought to be reformed to monitor whether multiple births originated spontaneously or from assisted-conception.

Being a mother of preterm multiples in the context of socioeconomic disadvantage: perceived stress and psychological symptoms / Ser mãe de múltiplos prematuros no contexto de desvantagem socioeconômica: estresse percebido e sintomas psicológicos

Abstract Objective: This study aimed to examine the differences between mothers of preterm multiples and mothers of preterm singletons regarding perceived stress and maternal psychological symptoms, and to explore the putative adverse amplified effect of socioeconomic disadvantage. Method: Ninety-five mothers of 1-year-olds born preterm participated in this cross-sectional study. Data collection was carried out in two public hospitals from Northern Portugal. To assess maternal perceived daily stress and psychological symptoms, mothers completed two questionnaires. Mothers reported on socioeconomic factors, including family poverty, parent unemployment, and low education, and two groups of family socioeconomic disadvantage were created. A child medical risk index was calculated. Results: Results indicated that mothers of preterm multiples reported higher levels of stress than mothers of preterm singletons. Moreover, and specifically regarding psychological functioning, mothers of preterm multiples reported more symptoms than mothers of preterm singletons, but only when living in a context of socioeconomic adversity. Conclusions: The results of the present study have important implications for practice. Mothers of preterm multiples are at higher risk to present mental health difficulties, in comparison to mothers of singletons, especially when exposed to socioeconomic adversities. The development of psychosocial intervention programs and public policies are of decisive importance in helping mothers of multiples adjust to parenthood.

Resumo Objetivo: Examinar as diferenças entre mães de múltiplos prematuros e mães de filhos únicos prematuros a respeito de estresse percebido e sintomas psicológicos maternos e explorar o efeito adverso amplificado putativo da desvantagem socioeconômica. Método: Participaram deste estudo transversal 95 mães de crianças de um ano nascidas prematuras. A coleta de dados foi feita em dois hospitais públicos do norte de Portugal. Para avaliar o estresse diário percebido e os sintomas psicológicos maternos, as mães responderam dois questionários. As mães relataram fatores socioeconômicos, incluindo pobreza familiar, desemprego dos pais e baixo nível de escolaridade, e foram criados dois grupos de desvantagem socioeconômica familiar. Foi calculado um índice de risco médico infantil. Resultados: Os resultados indicaram que as mães de múltiplos prematuros relataram maiores níveis de estresse do que as mães de filhos únicos prematuros. Além disso e especificamente com relação ao funcionamento psicológico, as mães de múltiplos prematuros relataram mais sintomas do que as mães de filhos únicos prematuros, porém apenas quando moravam em um contexto de adversidade socioeconômica. Conclusões: Os resultados deste estudo possuem importantes implicações para a prática. As mães de múltiplos prematuros apresentam maior risco de dificuldades de saúde mental, em comparação a mães de filhos únicos, principalmente quando expostas a adversidades socioeconômicas. O desenvolvimento de programas de intervenção psicossocial e políticas públicas é de importância decisiva ao ajudar as mães de filhos múltiplos a se ajustarem à maternidade.

Freemartinism in replacement ewe-lambs of the Ripollesa sheep breed

The freemartinism syndrome affects almost all female calves born as co-twins to male calves, whereas little is known about this phenomenon in female sheep. Within this context, 1,185 ewe-lambs from the Ripollesa sheep breed were genotyped for the presence of oY1 polymorphism (a non-autosomal region of the Y chromosome). Neither ewe-lambs from single births (856) nor ewe-lambs from all-female multiple births (170) were revealed as freemartins, whereas five of 159 ewe-lambs from multiple births with male co-twins were freemartins (3.15 ± 1.38%). All freemartin ewe-lambs were confirmed by physical examination of external genitalia. The results confirm a low incidence of freemartinism from heterosexual twin pregnancies in Ripollesa sheep.

Trends in Fetal and Perinatal Mortality in Korea (2009–2014): Comparison with Japan and the United States

Fetal death is an important indicator of national health care. In Korea, the fetal mortality rate is likely to increase due to advanced maternal age and multiple births, but there is limited research in this field. The authors investigated the characteristics of fetal deaths, the annual changes in the fetal mortality rate and the perinatal mortality rate in Korea, and compared them with those in Japan and the United States. Fetal deaths were restricted to those that occurred at 20 weeks of gestation or more. From 2009 to 2014, the overall mean fetal mortality rate was 8.5 per 1,000 live births and fetal deaths in Korea, 7.1 in Japan and 6.0 in the United States. While the birth rate in Korea declined by 2.1% between 2009 and 2014, the decrease in the number of fetal deaths was 34.5%. The fetal mortality rate in Korea declined by 32.9%, from 11.0 in 2009 to 7.4 in 2014, the largest decline among the 3 countries. In addition, rates for receiving prenatal care increased from 53.9% in 2009 to 75.0% in 2014. Perinatal mortality rate I and II were the lowest in Japan, followed by Korea and the United States, and Korea showed the greatest decrease in rate of perinatal mortality rate II. In this study, we identified that the indices of fetal deaths in Korea are improving rapidly. In order to maintain this trend, improvement of perinatal care level and stronger national medical support policies should be maintained continuously.

Contribution of Maternal Age Distribution to Incidence of Preterm Birth in Multiple Births; from 1997~98 to 2014~15

PURPOSE: To figure out the contribution of maternal age distribution to the preterm birth (PTB) rate of multiple births between 1997~98 and 2014~15. METHODS: Multiple birth certificate data of Korea Statistics were used for this analysis. There were 18,557 births in 1997~98 and 30,992 births in 2014~15. Kitagawa's decomposition method was used to examine the contribution of age-specific PTB rate and maternal age distribution of multiple births to overall increment of PTB rate in multiple births between 1997~98 and 2014~15. RESULTS: PTB rate of multiple births increased from 32.40 percent to 58.22 percent (odds ratio: 1.80, 95% confidence interval: 1.76~1.84) during 1997-2015. PTB rate of multiple births greatly increased for women aged 25~29 years (odds ratio: 2.09) during the same period. The rates increased 1.88 times for women aged ≤24 years, followed by women aged 30~34 years (OR: 1.65), women aged 35~39 years (1.54), and women aged ≥ 40 years (1.36). Most (78.7%) of the overall increment in PTB rate of multiple births was attributable to the increase in the dimension of women aged 30~34 years, and 49.9 percent for women aged 35~39 years. CONCLUSION: The total increment in the PTB rate of multiple births was explained by increase the proportion and the PTB rate of women aged 30~39 years. More research is needed to comprehend the contributing age factors to PTB rate of multiple births.

Contribution of Maternal Age Distribution to Incidence of Preterm Birth; 1997~99 and 2012~14 Singleton Birth Certificated Data of Korea

PURPOSE: The objective of the study was to compare contribution of maternal age to preterm birth (PTB) rates between 1997~99 and 2012~14. METHODS: We used 1997~99 (1,872,720 births) and 2012~14 (1,280,348 births) singleton birth certificated data of Korea Statistics excluding multiple birth and extra-marital birth cases. We decomposed the contributions of age-specific PTB rates and maternal age distribution (Kitagawa's decomposition method) to overall PTB rates during the period. Odds ratio (OR) and 95% confidence intervals were calculated from logistic regression to describe the secular trend of PTB rate by birth year and maternal age. RESULTS: The incidence of PTB increased 1.5 times, from 3.0 percent to 4.6 percent, during 1997~2014. After adjustment by logistic regression for infantile sex, parity and maternal age, the odds ratio of PTB in birth year of 2012~14 was 1.38 (95% confidence interval: 1.36~1.39), compared with incidence of PTB in 1997~99. During the period, PTB rates increased 1.79 times in women aged 20~24 years and 25~29 years (OR: 1.56), whereas rates remained stable in women aged 35 years and older (OR: range from 1.08 to 1.13). 87.5% of the overall increase in the PTB rates was attributable to the increase in the proportion of women aged 30~34 years, but these age group accounted for only a small portion of the increase in PTB rates (OR: 1.27). CONCLUSION: The remainder of the total increment in the PTB rates during the period was explained by increase the proportion of women aged 30~34 years. There was a need to close attention in this area to understand the contributing factors to the secular trend of PTB rates.

Modification of nutrition strategy for improvement of postnatal growth in very low birth weight infants / 소아과

PURPOSE: To identify the effects of modified parenteral nutrition (PN) and enteral nutrition (EN) regimens on the growth of very low birth weight (VLBW) infants. METHODS: The study included VLBW infants weighing <1,500 g, admitted to Chungnam National University Hospital between October 2010 and April 2014, who were alive at the time of discharge. Subjects were divided according to 3 periods: period 1 (n=37); prior to the PN and EN regimen being modified, period 2 (n=50); following the PN-only regimen modification, period 3 (n=37); following both PN and EN regimen modification. The modified PN regimen provided 3 g/kg/day of protein and 1 g/kg/day of lipid on the first day of life. The modified EN regimen provided 3.5-4.5 g/kg/day of protein and 150 kcal/kg/day of energy. We investigated growth rate, anthropometric measurements at 40 weeks postconceptional age (PCA) and the incidence of extrauterine growth restriction (EUGR) at 40 weeks PCA. RESULTS: Across the 3 periods, clinical characteristics, including gestational age, anthropometric measurements at birth, multiple births, sex, Apgar score, surfactant use and PDA treatment, were similar. Growth rates for weight and height, from time of full enteral feeding to 40 weeks PCA, were higher in period 3. Anthropometric measurements at 40 weeks PCA were greatest in period 3. Incidence of weight, height and head circumference EUGR at 40 weeks PCA decreased in period 3. CONCLUSION: Beginning PN earlier, with a greater supply of protein and energy during PN and EN, is advantageous for postnatal growth in VLBW infants.

Do induced twin pregnancies influence the obstetric and neonatal results of multiple births born before 32 weeks? Comparison to spontaneous gestation / Gestações gemelares induzidas modificam o resultado obstétrico e perinatal de partos antes da 32ª semana? Comparação com gestações espontâneas

PURPOSE: To compare obstetric outcomes of induced preterm twin births (under 32 weeks gestation) with those spontaneously conceived. METHODS: Prospective study of twin pregnancies (25 induced and 157 spontaneously conceived) developed over a period of 16 years in a tertiary obstetric center. Demographic factors, obstetric complications, gestational age at delivery, mode of delivery, birth weight and immediate newborn outcome were compared. RESULTS: The analysis of obstetrical complications concerning urinary or other infections, hypertensive disorders of pregnancy, gestational diabetes, fetal malformations, intrauterine fetal death, intrauterine growth restriction and intrauterine discordant growth reveal no significant statistical differences between the two groups. First trimester bleeding was higher in the induced group (24 versus 8.3%, p=0.029). The cesarean delivery rate was 52.2% in spontaneous gestations and 64% in induced gestations. Gestational age at delivery, birth weight, Apgar scores at first and fifth minutes, admissions to Neonatal Intensive Care Unit and puerperal complications show no statistically significant differences between the two groups. These results were independent of chorionicity and induction method. CONCLUSION: The mode of conception did not influence obstetric and neonatal outcomes. Although induced pregnancies have higher risk of first trimester bleeding, significant differences were not observed regarding other obstetric and puerperal complications and neonatal results. .

OBJETIVO: Comparar os resultados obstétricos de gestações gemelares induzidas com as concebidas espontaneamente, em partos ocorridos antes da 32ª semana de idade gestacional. MÉTODOS: Estudo prospectivo de gestações gemelares (25 induzidas e 157 concebidas espontaneamente) desenvolvido durante um período de 16 anos num centro terciário de Obstetrícia. Foram comparados fatores demográficos, complicações obstétricas, idade gestacional no parto, tipo de parto, peso ao nascer e o outcome imediato do recém-nascido. RESULTADOS: A análise das seguintes complicações obstétricas: infecções urinárias ou outras, distúrbios hipertensivos da gravidez, diabetes gestacional, malformações fetais, morte fetal intrauterina, restrição de crescimento intrauterino e crescimento intrauterino discordante não revelou diferenças estatísticas significativas entre os dois grupos. No grupo das gestações induzidas, observou-se maior taxa de metrorragias do 1º trimestre (24 versus 8,3%, p=0,029). A taxa de cesariana foi de 52,2% nas gestações espontâneas e 64% nas gestações induzidas. Idade gestacional no parto, peso ao nascer, índice de Apgar no primeiro e quinto minutos, internamento em unidade de cuidados intensivos neonatal e complicações puerperais não apresentam diferenças estatisticamente significantes entre os dois grupos. Esses resultados foram independentes do tipo de placentação e método de indução. CONCLUSÃO: O modo de concepção não influenciou os resultados obstétricos e neonatais. Embora as gestações induzidas tenham maior risco de metrorragias do primeiro trimestre, não foram observadas diferenças significativas em relação a outras complicações obstétricas, complicações puerperais e em relação aos resultados neonatais. .

Analysis of the incidence and perinatal outcomes of multiple births in Zhejiang Province from 2008 to 2013 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the trends of multiple births rates and their perinatal outcomes in Zhejiang province from 2008 to 2013.</p><p><b>METHODS</b>Data were obtained from hospital-based perinatal mortality surveillance system in Zhejiang, including all the hospitals in 30 monitoring counties (districts). All births (28 or more weeks of gestation) born in the monitoring hospitals were included in our study within 7 days after delivery from 2008 to 2013. Chi-square test was performed for statistical analyses for comparisons between regions. Trends in the incidence of multiple births and causes of perinatal death were analyzed using chi-square test for trend.</p><p><b>RESULTS</b>From 2008 to 2013, the multiple births rate in Zhejiang province was increased and the rates were 2.32% (5 551/239 636), 2.49% (6 053/243 452), 2.61% (6 549/250 594), 2.82% (7 758/275 105), 2.91% (8 803/302 447) and 3.06% (9 051/295 709), respectively. And the perinatal mortality rates for multiple births were 4.32% (240/5 551), 3.45% (209/6 053), 3.76% (246/6 549), 2.86% (222/7 758), 2.77% (244/8 803) and 2.11% (191/9 051), respectively. A significant drop in the perinatal mortality rates for multiple births was observed between 2008 and 2013 (χ(2) trend = 66.52, P < 0.001). There was a significantly greater risk for perinatal death to multiple births when compared with single birth (OR = 3.62, 95% CI: 3.42-3.83). The three leading causes of perinatal death for multiple births were birth defect, premature and/or low birth weight, and twin-twin transfusion syndrome.</p><p><b>CONCLUSION</b>The multiple births rates in Zhejiang province showed an increasing trend. The perinatal mortality rates for multiple births were decreased annually, however, it was still higher than those in developed countries.</p>

Características da carcaça e dos componentes não carcaça de cordeiros oriundos de parto simples ou duplo / Carcass and non-carcass traits of single and twin lambs

Um experimento foi conduzido com o objetivo de avaliar as características da carcaça e dos componentes não carcaça de cordeiros nascidos de parto simples ou duplo. Dezesseis cordeiros mestiços Texel × Ile de France, machos não castrados, foram desmamados aos 56 dias de idade e abatidos com aproximadamente 28kg de peso corporal. Imediatamente após o abate, cada componente corporal foi pesado separadamente, sendo as carcaças avaliadas após 24 horas de refrigeração a 2°C. Os cordeiros oriundos de parto simples apresentaram superioridade no peso e nos rendimentos da carcaça, além de maior área de olho de lombo. Por outro lado, proporcionalmente ao peso de corpo vazio, o rúmen é maior em cordeiros nascidos de parto duplo, o que resulta incremento da proporção de conteúdo gastrintestinal ao abate. Os resultados deste estudo indicam que, quando abatidos a um mesmo peso, cordeiros oriundos de parto simples possuem carcaças de melhor qualidade, em comparação a cordeiros nascidos de parto gemelar...

An experiment was conducted to evaluate the carcass and non-carcass traits of single and twin lambs. Sixteen Texel × Ile de France crossbred, non-castrated male lambs were weaned at 56 days of age and slaughtered at 28kg of body weight. Immediately after the slaughter each body component was individually weighed, while carcasses were evaluated after a 24h period of refrigeration at 2°C. Single lambs presented higher values of carcass weight and carcass dressing percentage. Moreover, the Longissimus muscle area was also greater for single lambs. On the other hand, as a proportion of empty body weight, rumen was greater for twin lambs, increasing their gastrointestinal content at slaughter. The results of this study indicated that at a same slaughter weight single lambs have better quality carcasses in comparison with those from twin lambs...

Incidence of low birth weight in Mazandaran province northern Iran

Low Birth Weight [LBW] has an important role in the mortality and morbidity of neonates and the incidence of LBW may vary across different environments. The aim of this study was to determine the incidence and some related factors of LBW in Mazandaran province. Northern Iran. In this longitudinal study, all live births that were born in 5 maternity hospitals in Mazandaran province, north of Iran in 2011, were evaluated. Data including birth weight, sex, maternal age, gestational age, living location, number of pregnancy and delivery, as well as multiple births were recorded in medical files. LBW neonates were compared with neonates whose birth weight was more than 2, 500 gram [control group]. Out of 3792 infants, 2.9% [CI 95%: 2.3-3.3] were of low birth weight. Sixty percent of the infants in the LBW group and 8.3% in the control group were preterm, [p< 0.001]. In the LBW group, 22.2% were multiple births, while 0.5% in control group were multiple births [p< 0.001], but other variable distributions such as sex, living location and mother's age did not differ between the LBW and the control groups [p>0.05]. Results show that the incidence of LBW in Mazandaran was low and prevention of preterm labor, educational intervention programs for high risk can be effective in the prevention of low birth weight

Análisis de la mortalidad perinatal, Hospital Miguel Servet, Zaragoza, España: 2000-2009 / Analysis of perinatal mortality, Miguel Servet Hospital, Zaragoza, Spain: 2000-2009

OBJETIVOS: Evaluar la mortalidad perinatal (MP) del Hospital Miguel Servet (2000-2009). Valorar su evolución, distribución según edad gestacional y peso de los recién nacidos (RN), y las posibles causas. MÉTODO: Análisis sobre un total de 44.409 RN >500 gramos y 402 nacidos muertos ó fallecidos antes de los 28 días completos de vida. Los datos se recogieron en un formulario siguiendo las recomendaciones de la FIGO y la novena Clasificación Internacional de Enfermedades. RESULTADOS: La MP ampliada global fue de 9,05/1000 nacidos, la mortalidad fetal de 4,91/1000 nacidos y la mortalidad neonatal 4,14/1000 nacidos vivos. La MP estándar fue de 4,73/1000 nacidos. Según la edad gestacional, un 79,6% de la MP fueron pretérminos; el 46,02% de los casos eran <1000 gramos y 59,95% <1500 gramos. Procedían de partos múltiples 92 RN (90 pretérminos); la MP de los embarazos gemelares fue 34,65/1000 nacidos. Las causas más frecuentes de MP eran: inmadurez extrema, <1000 gramos (46,02%), rotura prematura de membranas (23,13%), gestaciones múltiples (22,89%), complicaciones de placenta o cordón (21,64%), hipoxia intrauterina y asfixia al nacer (21,64%), y malformaciones congénitas y cromosomopatías (18,9%). CONCLUSIÓN: La MP está gravada por la prematuridad, el bajo peso extremo y los embarazos múltiples, disminuyendo paulatinamente a expensas de la mortalidad neonatal.

OBJECTIVE: To evaluate Hospital Miguel Servet perinatal mortality (PM) during the years 2000-2009, valuing its evolution and distribution according to gestational age and birth weight. Maternal and fetal possible causes are analized. METHODS: 44.409 newborns of >500 grams or 22 weeks gestational age, were studied. The total number of perinatal deaths was 402 containing late neonatal deaths (to 28 completed days of live). The data for each case of perinatal mortality were recorded in a form following FIGO recommendations and the 9th International Classification of Diseases. RESULTS: Extended PM rate was 9.05/1000 newborns, fetal mortality 4.91/1000 newborns and neonatal mortality 4.14/1000 live births. Standard PM was 4.73/1000 newborns. According to gestational age, 79.60% were preterm deliveries. Considering birth weights, 46.02% were extremely low birth weight (<1000 grams), and 59.95% were <1500 grams. The number of perinatal deaths in multiple pregnancies was 92 (90 preterm deliveries). PM in twins was 34.65/1000 newborns. Main causes of death were extreme immaturity (<1000 grams) in 46.02%, premature rupture of membranes (23.13%), multiple deliveries (22.89%), complications of placenta or umbilical cord (21.64%), intrauterine hypoxia and asphyxia at birth in 21.64% of the cases, and congenital malformations and chromosomopaties (18.90%). CONCLUSIONS: PM is encumbered by prematurity, extremely low birth weight and múltiple pregnancies. Decrease of perinatal mortality had occurred mainly at the expense of neonatal mortality.

Changes in Statistical Birth Data Related to Maternity and Newborn over the Past 15 Years in Korea / 대한주산의학회잡지

PURPOSE: The statistical birth data related to maternity and newborns over the past 15 years in Korea was analyzed in order to review the changing patterns of maternity and newborns in Korea. METHODS: Statistical data after 1995 in Korea were obtained from the Statistics Korea. Birth data related to maternity (distribution of birth rate, maternal age, advanced maternal age group, rank of birth, and time of pregnancy) and newborn (distribution of number of births, birth weight, ratio of sex, and multiple births) were analyzed. RESULTS: The average age of maternity is increasing while births in an advanced age has also increased from 4.7% in 1995 to 15.5% in 2009. There was a decrease in the total number of births, total birth rate and average birth weight. The rate of premature births in an advanced age occupied more than 6% of this study. The ratio of sex from the third born child and beyond has been relieved. The rate of multiple births has increased. The birth rate within two years of cohabitation before giving birth to a couple's first child has decreased. CONCLUSIONS: The rates of newborns requiring perinatal care such as births of prematurity, low birth weight infants, multiple pregnancies, etc are increasing. This is in relation to the increase in age of maternity and number of pregnancies in an advanced age. Therefore, there is an increase demand for strategies in order to decrease the age of maternity and the rate of pregnancies in an advanced age.

Childhood Cancer Mortality and Birth Characteristics in Korea: A National Population-based Birth Cohort Study

To examine the relationship between birth characteristics and childhood cancer mortality, a retrospective cohort study of Korean children was conducted using data collected by the national birth register between 1995 and 2006, which were then individually linked to death data. A cohort of 6,479,406 children was followed from birth until their death or until December 31, 2006. Poisson regression analyses were used to calculate rate ratios of childhood cancer deaths according to birth characteristics. A total of 1,469 cancer deaths were noted and the childhood cancer mortality rate was found to be 3.43 per 100,000 person-years in Korea during the period of 1995-2006. The birth characteristics examined in this study (i.e. , birth weight, gestational age, multiple births, parental ages, and number of siblings) were generally found to be not significantly associated with childhood cancer mortality, and the associations did not vary meaningfully with gender nor with cancer sites. However, among children aged 5-11 yr, higher birth weight was associated with elevated childhood cancer mortality (rate ratio = 1.28, 95% confidence interval 1.04-1.58). Our results offer no overall associations between childhood cancer mortality and birth characteristics, but suggest that the association may be specific to age group.

The changing trends in live birth statistics in Korea, 1970 to 2010 / 소아과

Although Korean population has been growing steadily during the past four decades, the nation is rapidly becoming an aging society because of its declining birth rate combined with an increasing life expectancy. In addition, Korea has one of the lowest fertility rates in the world due to fewer married couples, advanced maternal age, and falling birth rate. The prevalence of low birth weight infants and multiple births has been increased compared with the decrease in the birth rate. Moreover, the number of congenital anomalies is expected to increase due to the advanced maternal age. In addition, the number of interracial children is expected to increase due to the rise in the number of international marriages. However, the maternal education level is high, single-mother birth rate is low, and the gender imbalance has lessened. The number of overweight babies has been decreased, as more pregnant women are receiving adequate prenatal care. Compared to the Asian average birth weight, the average birth weight is the highest in Asia. Moreover, the rate of low birth weight infants is low, and infant mortality is similarly low across Asia. Using birth data from Statistics Korea and studies of birth outcomes in Korea and abroad, this study aimed to assess the changes in maternal and infant characteristics associated with birth outcomes during the past four decades and identify necessary information infrastructures to study countermeasures the decrease in birth rate and increase in low birth weight infants in Korea.

The changing trends in live birth statistics in Korea, 1970 to 2010 / 소아과

Although Korean population has been growing steadily during the past four decades, the nation is rapidly becoming an aging society because of its declining birth rate combined with an increasing life expectancy. In addition, Korea has one of the lowest fertility rates in the world due to fewer married couples, advanced maternal age, and falling birth rate. The prevalence of low birth weight infants and multiple births has been increased compared with the decrease in the birth rate. Moreover, the number of congenital anomalies is expected to increase due to the advanced maternal age. In addition, the number of interracial children is expected to increase due to the rise in the number of international marriages. However, the maternal education level is high, single-mother birth rate is low, and the gender imbalance has lessened. The number of overweight babies has been decreased, as more pregnant women are receiving adequate prenatal care. Compared to the Asian average birth weight, the average birth weight is the highest in Asia. Moreover, the rate of low birth weight infants is low, and infant mortality is similarly low across Asia. Using birth data from Statistics Korea and studies of birth outcomes in Korea and abroad, this study aimed to assess the changes in maternal and infant characteristics associated with birth outcomes during the past four decades and identify necessary information infrastructures to study countermeasures the decrease in birth rate and increase in low birth weight infants in Korea.

Evaluation of the growth process of infants conceived by assisted reproductive techniques at royan institute from birth to 9 months

Due to recent scientific progress in assisted reproductive techniques [ART], infertile couples can now become fertile. Thus, a number of infants in our country are the results of these costly interventions. This study has been undertaken to evaluate the physical growth process of different methods of ART infants by standard growth charts from birth until nine months of age. This was a descriptive cross-sectional study of 333 infants conceived through ART [intracytoplasmic sperm injection [ICSI] and in vitro fertilization [IVF]] at Royan Institute. A sequential, non-random sampling method in a period of 22 months was used. Their growth was assessed by measuring infants' weight, height and head circumference, and physical examination. The growth patterns were calculated by recording the values in standard growth charts. The final analysis was done with SPSS version 16 and by using Chi-square test. In comparison with growth charts, the weights of one-third of the infants were less than two standard deviations [SD] at birth and one-fourth had head circumference less than three SD at birth. Low birth weight [LEW] infants were six times more than infants of normal population. From birth to six months of age, growth abnormalities were seen in a substantial number of infants. However, at nine months of age, there was no significant difference observed between infants conceived by different methods of ART [IVF and ICSI]. Multiple births are the most important confounding factor impacting the growth process of ART infants. Multiple pregnancies can lead to low birth weight, height and head circumference, and growth abnormalities up to six months of age. This abnormality improves by increasing age of the infants

Multiple births conceived by assisted reproductive technology in Korea / 소아과

PURPOSE: The recent trends of multiple births (MBs) conceived by assisted reproductive technology (ART) in Korea were analyzed as well as the relationship with maternal age, especially advanced maternal age. METHODS: Data were obtained from the Korean Statistical Information Service and annual ART reports from the ART committee of the Korean Society of Obstetrics and Gynecology. RESULTS: MBs increased from the early 1990s; there was a 275% increase by 2008. The number of total live births was 448,153 and MBs accounted for 10,767; the MB rate was 24.0% in 2006. Among 2,326 deliveries conceived by ART, multiple deliveries accounted for 786 (33.8%). The total number of live births with ART was 3,125 and 1,585 (50.7%) of them were MBs. During 2006, 14.7% of the entire MBs in Korea were associated with ART. The proportion of women of advanced maternal age was much higher in the ART group than in the total live birth group. CONCLUSION: MBs in women of advanced maternal age have been increasing in Korea with the use of ART. The results of this study showed that ART was a significant factor associated with the increase in MBs in Korea.