Talk:Birth - Preterm
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Cite this page: Hill, M.A. (2024, May 6) Embryology Birth - Preterm. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Birth_-_Preterm |
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Preterm Birth
<pubmed limit=10>Preterm+Birth</pubmed>
2012
Prepregnancy maternal body mass index and preterm delivery
Am J Obstet Gynecol. 2012 Sep;207(3):212.e1-7. doi: 10.1016/j.ajog.2012.06.002. Epub 2012 Jun 11.
Khatibi A, Brantsaeter AL, Sengpiel V, Kacerovsky M, Magnus P, Morken NH, Myhre R, Gunnes N, Jacobsson B. Source Department of Obstetrics and Gynecology, Sahlgrenska University Hospital/East, Gothenburg, Sweden. ali.khatibi_esfangani@vgregion.se
Abstract
OBJECTIVE: The purpose of this study was to determine the influence of maternal prepregnancy body mass index on preterm delivery (PTD), controlling for health and lifestyle variables. STUDY DESIGN: Prospective data were from 83,544 pregnancies in the Norwegian Mother and Child Cohort Study. PTD was divided into early PTD (22 + 0 to 31 + 6 weeks' gestation) and late PTD (32 + 0 to 36 + 6 weeks' gestation). RESULTS: The overall prevalence of PTD was 5.1%. Increased body mass index was associated with an increased risk of PTD; adjusted odds ratio (aOR) ranged from 1.11 (95% confidence interval [CI], 1.03-1.20) for preobesity to 2.00 (95% CI, 1.48-2.71) for grade-III obesity in the group that included all PTD subgroups. Grade-III obese women had an increased risk of both early and late PTD: aOR, 3.24 (95% CI, 1.71-6.14) and 1.81 (95% CI, 1.29-2.54), respectively. CONCLUSION: Prepregnancy maternal overweight increases the risk of both early and late PTD. Copyright © 2012 Mosby, Inc. All rights reserved.
PMID 22835494
World Health Organization
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Academic Achievement Varies With Gestational Age Among Children Born at Term
Pediatrics. 2012 Jul 2. [Epub ahead of print]
Noble KG, Fifer WP, Rauh VA, Nomura Y, Andrews HF. Source Departments of Pediatrics.
Abstract
OBJECTIVE: The goal of this study was to examine the degree to which children born within the "normal term" range of 37 to 41 weeks' gestation vary in terms of school achievement. METHODS: This study analyzed data from 128 050 singleton births born between 37 and 41 weeks' gestation in a large US city. Data were extracted from city birth records to assess a number of obstetric, social, and economic variables, at both the individual and community levels. Birth data were then matched with public school records of standardized city-wide third-grade reading and math tests. Specifically, we assessed (1) whether children born within the normal term range of 37 to 41 weeks' gestation show differences in reading and/or math ability 8 years later as a function of gestational age, and (2) the degree to which a wide range of individual- and community-level social and biological factors mediate this effect. RESULTS: Analyses revealed that gestational age within the normal term range was significantly and positively related to reading and math scores in third grade, with achievement scores for children born at 37 and 38 weeks significantly lower than those for children born at 39, 40, or 41 weeks. This effect was independent of birth weight, as well as a number of other obstetric, social, and economic factors. CONCLUSIONS: Earlier normal term birth may be a characteristic considered by researchers, clinicians, and parents to help identify children who may be at risk for poorer school performance.
PMID 22753563
Preterm Birth and Psychiatric Disorders in Young Adult Life
Arch Gen Psychiatry. 2012 Jun 1:610-617. doi: 10.1001/archgenpsychiatry.2011.1374. [Epub ahead of print]
Nosarti C, Reichenberg A, Murray RM, Cnattingius S, Lambe MP, Yin L, Maccabe J, Rifkin L, Hultman CM.
Abstract
CONTEXT Preterm birth, intrauterine growth restriction, and delivery-related hypoxia have been associated with schizophrenia. It is unclear whether these associations pertain to other adult-onset psychiatric disorders and whether these perinatal events are independent. OBJECTIVE To investigate the relationships among gestational age, nonoptimal fetal growth, Apgar score, and various psychiatric disorders in young adult life. DESIGN Historical population-based cohort study. SETTING Identification of adult-onset psychiatric admissions using data from the National Board of Health and Welfare, Stockholm, Sweden. PARTICIPANTS All live-born individuals registered in the nationwide Swedish Medical Birth Register between 1973 and 1985 and living in Sweden at age 16 years by December 2002 (n = 1 301 522). MAIN OUTCOME MEASURES Psychiatric hospitalization with nonaffective psychosis, bipolar affective disorder, depressive disorder, eating disorder, drug dependency, or alcohol dependency, diagnosed according to the International Classification of Diseases codes for 8 through 10. Cox proportional hazards regression models were used to estimate hazard ratios and 95% CIs. RESULTS Preterm birth was significantly associated with increased risk of psychiatric hospitalization in adulthood (defined as ≥16 years of age) in a monotonic manner across a range of psychiatric disorders. Compared with term births (37-41 weeks), those born at 32 to 36 weeks' gestation were 1.6 (95% CI, 1.1-2.3) times more likely to have nonaffective psychosis, 1.3 (95% CI, 1.1-1.7) times more likely to have depressive disorder, and 2.7 (95% CI, 1.6-4.5) times more likely to have bipolar affective disorder. Those born at less than 32 weeks' gestation were 2.5 (95% CI, 1.0-6.0) times more likely to have nonaffective psychosis, 2.9 (95% CI, 1.8-4.6) times more likely to have depressive disorder, and 7.4 (95% CI, 2.7-20.6) times more likely to have bipolar affective disorder. CONCLUSIONS The vulnerability for hospitalization with a range of psychiatric diagnoses may increase with younger gestational age. Similar associations were not observed for nonoptimal fetal growth and low Apgar score.
PMID 22660967
Antenatal magnesium sulfate and neuroprotection
Curr Opin Pediatr. 2012 Apr;24(2):154-9.
Doyle LW. Source Murdoch Childrens Research Institute, The Royal Women's Hospital, University of Melbourne, Melbourne, Victoria, Australia. lwd@unimelb.edu.au
Abstract
PURPOSE OF REVIEW: Antenatal magnesium sulfate may reduce the excessive rates of cerebral palsy in survivors of very preterm birth. RECENT FINDINGS: There are five randomized controlled trials of magnesium sulfate therapy given to the mother prior to very preterm birth which have reported neurological outcomes for the child, in four of which the primary aim of the trial was neuroprotection for the fetus. From meta-analysis of these randomized trials, the rate of cerebral palsy was reduced by magnesium sulfate [relative risk (RR) = 0.69; 95% confidence interval (CI) = 0.54-0.87; five trials; 6145 infants). Magnesium sulfate also lowered the rate of substantial motor dysfunction in early childhood (RR = 0.61; 95% CI = 0.44-0.85; four trials; 5980 infants). In addition, where the main aim of the trial was neuroprotection of the fetus, the rates of the combined outcomes of death or cerebral palsy (RR = 0.86; 95% CI = 0.74-0.98; four trials; 4446 infants) and death or substantial motor dysfunction (RR = 0.85; 95% CI = 0.73-0.98; three trials; 4387 infants) were significantly lower with magnesium. SUMMARY: On the basis of these findings several countries have now released clinical practice guidelines recommending antenatal magnesium sulfate prior to very preterm birth.
PMID 22227787
Chloride Balance in Preterm Infants during the First Week of Life
Int J Pediatr. 2012;2012:931597. Epub 2012 Mar 8.
Iacobelli S, Kermorvant-Duchemin E, Bonsante F, Lapillonne A, Gouyon JB. Source Neonatology and NICU, GHSR, CHR, BP 350, 97448 Saint Pierre Cedex, Réunion, France.
Abstract
Objective. To describe the chloride balance in infants born 25-32-week gestation, analyze the association of chloride changes with hydroelectrolytic status and their relationship with perinatal conditions, morbidities, and neurological outcome. Methods. For 7 days after birth, sodium and chloride balance, plasma potassium, phosphate, and total carbon dioxide (tCO(2)) were prospectively determined and strong ion difference (SID) calculated. Three multivariate regression analyses were performed to identify factors associated with high plasma chloride concentration, low SID, and low tCO(2). Results. 107 infants were studied. Plasma chloride concentration was significantly positively associated with plasma sodium concentration. Higher plasma chloride and lower SID were significantly associated with lower plasma tCO(2). Chloride intake was the main independent factor associated with high plasma chloride, low SID, and low plasma tCO(2), with lesser contribution of sodium intake and low gestational age (GA). Also, patent ductus arteriosus and birth weight loss were independent factors affecting plasma chloride and SID. Neither high chloride levels nor low SID were associated to impaired neurological outcome. Conclusions. In preterm infants, chloride balance is influenced by GA and by interrelationship between sodium and chloride intake. High chloride levels are associated with metabolic acidosis but not related to increased risk of impaired neurological outcome.
PMID 22505945
Transvaginal sonographic evaluation of the cervix in asymptomatic singleton pregnancy and management options in short cervix
J Pregnancy. 2012;2012:201628. Epub 2012 Feb 22. Arisoy R, Yayla M. Source Department of Obstetrics and Gynaecology, Gole State Hospital, 34660 Ardahan, Turkey.
Abstract
Preterm delivery (PTD), defined as birth before 37 completed weeks of gestation, is the leading cause of perinatal morbidity and mortality. Evaluation of the cervical morphology and biometry with transvaginal ultrasonography at 16-24 weeks of gestation is a useful tool to predict the risk of preterm birth in low- and high-risk singleton pregnancies. For instance, a sonographic cervical length (CL) > 30 mm and present cervical gland area have a 96-97% negative predictive value for preterm delivery at <37 weeks. Available evidence supports the use of progesterone to women with cervical length ≤25 mm, irrespective of other risk factors. In women with prior spontaneous PTD with asymptomatic cervical shortening (CL ≤ 25 mm), prophylactic cerclage procedure must be performed and weekly to every two weeks follow-up is essential. This article reviews the evidence in support of the clinical introduction of transvaginal sonography for both the prediction and management of spontaneous preterm labour.
PMID 22523687
http://www.hindawi.com/journals/jp/2012/201628/
Editorial - Prevention and Management of Preterm Birth
Jacquemyn Y, Lamont R, Cornette J, Helmer H. J Pregnancy. 2012;2012:610364. Epub 2012 Mar 18. No abstract available.
Prevention and treatment of preterm delivery is not one of the success stories of modern medicine, preterm birth constitutes the major determinant of perinatal mortality and morbidity, and the long-term results of being born too early often lead to a shorter, less healthy life and a more difficult school and professional career. Different methods have been introduced to predict the advent of preterm labour in asymptomatic women, including fetal fibronectin and transvaginal ultrasound cervical length measurement. R. Arisoy and M. Yayla present data on the evaluation of the cervix in asymptomatic singleton pregnancies; they also address the most frustrating issue: what measures to take once a short cervix has been detected. They restrict their study to singleton pregnancies; although both cervical length and fetal fibronectin are good predictors of preterm delivery in twins, no intervention has proven useful in twins: vaginal progesteron makes no difference and cerclage even worsens the outcome.
Possibilities for real primary prevention are rare and include treatment of asymptomatic bacteriuria and periodontal disease. O. Huck et al. elaborate this last issue and present an excellent overview on both epidemiologic and pathophysiologic data. Another method proposed for primary prevention of preterm birth is the use of progesteron, including vaginal progesteron and systemic 17-hydroxyprogesterone caproate. Starting progesterone treatment can be based not only on cervical length or vaginal fibronectin but also on past obstetrical history. C. E. Ransom et al. comment on the use of 17-hydroxyprogesterone caproate and the influence of obstetric history.
Some newer methods are on the border of being introduced to clinical practice; one such candidate is near-infrared spectroscopy. K. M. Power and colleagues present the use of near-infrared spectroscopy of amniotic fluid to assess preterm delivery.
Once preterm labour has been established, tocolytics are (all too) often used, and what their exact place in treatment is remains open for discussion. Hubinont and F. Debieve present a concise update on tocolysis. In case preterm delivery seems unavoidable, the optimal mode of fetal monitoring and the mode of delivery have to be chosen. Fetal heart rate monitoring in the preterm period constitutes a special challenge and is further commented by K. Afors and E. Chandraharan, while S. R. Bhatta and C. R. Keriakos discuss the optimal way of delivering the preterm baby in vertex position.
As the articles in this issue demonstrate, preterm labour and delivery constitute one of the major challenges of obstetrics in the 21st century. PMID 22550589
http://www.hindawi.com/journals/jp/2012/610364/
WHO Report
The first-ever country-by-country estimate of premature births finds that 15 million babies a year are born preterm - more than one in 10 live births. Although more than 60% of preterm births are in sub-Saharan Africa and south Asia, they are also a problem for some high-income countries, including the USA and Brazil. Both rank among the 10 countries with the highest number of preterm births. In the USA, about 12% of all births are preterm, a percentage far higher than in Europe or other developed countries. ...
The Partnership (PMNCH) - joins the maternal, newborn and child health (MNCH) communities into an alliance of more than 350 members to ensure that all women, infants and children not only remain healthy, but thrive. Born Too Soon: The Global Action Report on Preterm Birth
http://apps.who.int/datacol/survey_result.asp?survey_id=258&view_id=274&respondent_id=100490
Effects of gestational age at birth on health outcomes at 3 and 5 years of age: population based cohort study
BMJ. 2012 Mar 1;344:e896. doi: 10.1136/bmj.e896.
Boyle EM, Poulsen G, Field DJ, Kurinczuk JJ, Wolke D, Alfirevic Z, Quigley MA. Source Department of Health Sciences, University of Leicester, Leicester LE1 6TP, UK. eb124@le.ac.uk Abstract OBJECTIVE: To investigate the burden of later disease associated with moderate/late preterm (32-36 weeks) and early term (37-38 weeks) birth. DESIGN: Secondary analysis of data from the Millennium Cohort Study (MCS). SETTING: Longitudinal study of infants born in the United Kingdom between 2000 and 2002. PARTICIPANTS: 18,818 infants participated in the MCS. Effects of gestational age at birth on health outcomes at 3 (n = 14,273) and 5 years (n = 14,056) of age were analysed. MAIN OUTCOME MEASURES: Growth, hospital admissions, longstanding illness/disability, wheezing/asthma, use of prescribed drugs, and parental rating of their children's health. RESULTS: Measures of general health, hospital admissions, and longstanding illness showed a gradient of increasing risk of poorer outcome with decreasing gestation, suggesting a "dose-response" effect of prematurity. The greatest contribution to disease burden at 3 and 5 years was in children born late/moderate preterm or early term. Population attributable fractions for having at least three hospital admissions between 9 months and 5 years were 5.7% (95% confidence interval 2.0% to 10.0%) for birth at 32-36 weeks and 7.2% (1.4% to 13.6%) for birth at 37-38 weeks, compared with 3.8% (1.3% to 6.5%) for children born very preterm (<32 weeks). Similarly, 2.7% (1.1% to 4.3%), 5.4% (2.4% to 8.6%), and 5.4% (0.7% to 10.5%) of limiting longstanding illness at 5 years were attributed to very preterm birth, moderate/late preterm birth, and early term birth. CONCLUSIONS: These results suggest that health outcomes of moderate/late preterm and early term babies are worse than those of full term babies. Additional research should quantify how much of the effect is due to maternal/fetal complications rather than prematurity itself. Irrespective of the reason for preterm birth, large numbers of these babies present a greater burden on public health services than very preterm babies.
PMID 22381676
Patterns and outcomes of preterm hospital admissions during pregnancy in NSW, 2001-2008
Med J Aust. 2012 Mar 5;196(4):261-5.
Badgery-Parker T, Ford JB, Jenkins MG, Morris JM, Roberts CL.
Source
Centre for Epidemiology and Research, NSW Ministry of Health, Sydney, NSW, Australia. clroberts@med.usyd.edu.au.
Abstract
OBJECTIVE: To assess the frequency and outcomes of preterm hospital admissions during pregnancy, with a focus on transfers to higher levels of care.
DESIGN: Population-based cohort study using linked population data.
SETTING AND SUBJECTS: Women who were admitted to hospital in weeks 20-36 of pregnancy (preterm) and gave birth to a liveborn singleton infant in New South Wales during 2001-2008.
MAIN OUTCOME MEASURE: Numbers of preterm admissions of pregnant women who were discharged without giving birth, were transferred to higher care, or who gave birth.
RESULTS: 110 439 pregnancies (16.0%) involved at least one preterm admission. After their initial preterm admission, 71.9% of women were discharged, 6.3% were transferred and 21.8% gave birth. Median gestational age at admission was 33 weeks and median time to discharge, transfer or giving birth was 1 day. Most women who were transferred or who gave birth had been admitted for preterm rupture of membranes or preterm labour. Of the women who were admitted or were transferred with suspected preterm labour, only 29% and 38%, respectively, gave birth. Compared with other admitted women, women having a first birth, public patients and those living in areas of low socioeconomic status were more likely to be transferred or to give birth. As gestational age increased, the proportion of women transferred decreased and the proportion giving birth increased. Infants born after maternal transfer had lower gestational age and more adverse outcomes than those born without maternal transfer.
CONCLUSIONS: Preterm hospital admission affects one in six women with singleton pregnancies. Methods that could improve assessment of labour status have a large potential to reduce the burden on maternity services. The increased morbidity for infants born after maternal transfer suggests women with high-risk pregnancies are being appropriately identified.
PMID 22409693
2011
Perinatal morbidity associated with late preterm deliveries compared with deliveries between 37 and 40 weeks of gestation
BJOG. 2011 Nov;118(12):1446-54. doi: 10.1111/j.1471-0528.2011.03045.x. Epub 2011 Aug 22.
Cheng YW, Kaimal AJ, Bruckner TA, Halloran DR, Caughey AB. Source Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 94143-0132, USA. yvecheng@hotmail.com Erratum in BJOG. 2011 Dec;118(13):1687. Hallaron, D R [corrected to Halloran, D R]. Abstract OBJECTIVE: To estimate the risk of short-term complications in neonates born between 34 and 36 weeks of gestation. DESIGN: This is a retrospective cohort study. SETTING: Deliveries in 2005 in the USA. POPULATION: Singleton live births between 34 and 40 weeks of gestation. METHODS: Gestational age was subgrouped into 34, 35, 36 and 37-40 completed weeks of gestation. Statistical comparisons were performed using chi-square test and multivariable logistic regression models, with 37-40 weeks of gestation designated as referent. MAIN OUTCOME MEASURES: Perinatal morbidities, including 5-minute Apgar scores, hyaline membrane disease, neonatal sepsis/antibiotics use, and admission to the intensive care unit. RESULTS: In all, 175,112 neonates were born between 34 and 36 weeks in 2005. Compared with neonates born between 37 and 40 weeks, neonates born at 34 weeks had higher odds of 5-minute Apgar <7 (adjusted odds ratio [aOR] 5.51, 95% CI 5.16-5.88), hyaline membrane disease (aOR 10.2, 95% CI 9.44-10.9), mechanical ventilation use >6 hours (aOR 9.78, 95% CI 8.99-10.6) and antibiotic use (aOR 9.00, 95% CI 8.43-9.60). Neonates born at 35 weeks were similarly at risk of morbidity, with higher odds of 5-minute Apgar <7 (aOR 3.42, 95% CI 3.23-3.63), surfactant use (aOR 3.74, 95% CI 3.21-4.22), ventilation use >6 hours (aOR 5.53, 95% CI 5.11-5.99) and neonatal intensive-care unit admission (aOR 11.3, 95% CI 11.0-11.7). Neonates born at 36 weeks remain at higher risk of morbidity compared with deliveries at 37-40 weeks of gestation. CONCLUSIONS: Although the risk of undesirable neonatal outcomes decreases with increasing gestational age, the risk of neonatal complications in late preterm births remains higher compared with infants delivered at 37-40 weeks of gestation. © 2011 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2011 RCOG.
PMID 21883872
Children's Brain Development Benefits from Longer Gestation
Front Psychol. 2011;2:1. Epub 2011 Feb 9.
Davis EP, Buss C, Muftuler LT, Head K, Hasso A, Wing DA, Hobel C, Sandman CA. Source Women and Children's Health and Well-Being Project, Department of Psychiatry and Human Behavior, University of California Irvine Orange, CA, USA. Abstract Disruptions to brain development associated with shortened gestation place individuals at risk for the development of behavioral and psychological dysfunction throughout the lifespan. The purpose of the present study was to determine if the benefit for brain development conferred by increased gestational length exists on a continuum across the gestational age spectrum among healthy children with a stable neonatal course. Neurodevelopment was evaluated with structural magnetic resonance imaging in 100 healthy right-handed 6- to 10-year-old children born between 28 and 41 gestational weeks with a stable neonatal course. Data indicate that a longer gestational period confers an advantage for neurodevelopment. Longer duration of gestation was associated with region-specific increases in gray matter density. Further, the benefit of longer gestation for brain development was present even when only children born full term were considered. These findings demonstrate that even modest decreases in the duration of gestation can exert profound and lasting effects on neurodevelopment for both term and preterm infants and may contribute to long-term risk for health and disease.
PMID 21713130
The surprising composition of the salivary proteome of preterm human newborn
Saliva is a body fluid of a unique composition devoted to protect the mouth cavity and the digestive tract. A quantitative label-free MS analysis showed protein levels altered in relation to the postconceptional age and suggested coordinate and hierarchical functions for these proteins during development. In summary, this study shows for the first time that analysis of these proteins in saliva of preterm newborns might represent a non-invasive way to obtain precious information of the molecular mechanisms of development of human fetal oral structures.
PMID 20943598
2009
Differing prevalence and diversity of bacterial species in fetal membranes from very preterm and term labor
PLoS One. 2009 Dec 8;4(12):e8205.
Jones HE, Harris KA, Azizia M, Bank L, Carpenter B, Hartley JC, Klein N, Peebles D. Source Infectious Diseases and Microbiology Unit, Institute of Child Health, London, United Kingdom. h.jones@ich.ucl.ac.uk
Abstract
BACKGROUND: Intrauterine infection may play a role in preterm delivery due to spontaneous preterm labor (PTL) and preterm prolonged rupture of membranes (PPROM). Because bacteria previously associated with preterm delivery are often difficult to culture, a molecular biology approach was used to identify bacterial DNA in placenta and fetal membranes. METHODOLOGY/PRINCIPAL FINDINGS: We used broad-range 16S rDNA PCR and species-specific, real-time assays to amplify bacterial DNA from fetal membranes and placenta. 74 women were recruited to the following groups: PPROM <32 weeks (n = 26; 11 caesarean); PTL with intact membranes <32 weeks (n = 19; all vaginal birth); indicated preterm delivery <32 weeks (n = 8; all caesarean); term (n = 21; 11 caesarean). 50% (5/10) of term vaginal deliveries were positive for bacterial DNA. However, little spread was observed through tissues and species diversity was restricted. Minimal bacteria were detected in term elective section or indicated preterm deliveries. Bacterial prevalence was significantly increased in samples from PTL with intact membranes [89% (17/19) versus 50% (5/10) in term vaginal delivery p = 0.03] and PPROM (CS) [55% (6/11) versus 0% (0/11) in term elective CS, p = 0.01]. In addition, bacterial spread and diversity was greater in the preterm groups with 68% (13/19) PTL group having 3 or more positive samples and over 60% (12/19) showing two or more bacterial species (versus 20% (2/10) in term vaginal deliveries). Blood monocytes from women with PTL with intact membranes and PPROM who were 16S bacterial positive showed greater level of immune paresis (p = 0.03). A positive PCR result was associated with histological chorioamnionitis in preterm deliveries. CONCLUSION/SIGNIFICANCE: Bacteria are found in both preterm and term fetal membranes. A greater spread and diversity of bacterial species were found in tissues of women who had very preterm births. It is unclear to what extent the greater bacterial prevalence observed in all vaginal delivery groups reflects bacterial contamination or colonization of membranes during labor. Bacteria positive preterm tissues are associated with histological chorioamnionitis and a pronounced maternal immune paresis.
PMID 19997613
