How Is Cigarette Smoking Harmful to Unborn Babies
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Smoking during pregnancy and harm reduction in birth weight: a cross-exclusive study
BMC Pregnancy and Childbirth volume 18, Commodity number:67 (2018) Cite this commodity
Abstract
Background
Unlike studies have shown the advantages of abstinence from cigarette smoking during pregnancy to promote full fetal evolution. Given that pregnant women do not always abjure from smoking, this study aimed to analyze the effect of different intensities of smoking on birth weight of the newborn.
Methods
A cross-sectional study was adopted to explore smoking in a population of significant women from a medium-sized city in São Paulo state, Brazil, who gave birth between Jan and June of 2012. Data were collected from maternal and pediatric medical files and, where data were absent, they were collected by interview during hospitalization for delivery. For data analysis, the effect of potential confounding variables on newborn birth weight was estimated using a gamma response model. The effect of the identified misreckoning variables was also estimated past means of a gamma response regression model.
Results
The prevalence of smoking during pregnancy was xiii.four% in the study population. In full-term infants, nascence weight decreased as the category of cigarette number per day increased, with a significant weight reduction as of the category vi to 10 cigarettes per twenty-four hours. Compared with infants born to non smoking mothers, mean birth weight was 320 g lower in infants whose mothers smoked 6 to x cigarettes per day and 435 g lower in infants whose mothers smoked 11 to 40 cigarettes per twenty-four hour period during pregnancy.
Conclusions
Based on the study results and the principle of harm reduction, if a meaning woman is unable to quit smoking, she should be encouraged to reduce consumption to less than six cigarettes per mean solar day.
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Background
Since the adoption of the Framework Convention on Tobacco by member countries of the Earth Health Organization in 2003, in that location have been important global actions to control smoking. Despite this, the smoking "epidemic" has grown in some countries because of the marketing power of the tobacco manufacture, population growth in countries with extensive consumption, and the number of highly dependent people who are unable to quit smoking [1].
The Centers for Disease Control and Prevention has estimated that nineteen.0% of American adults smoked cigarettes in 2011 [2]. The Special Survey on Smoking, a supplement to the 2008 Brazilian National Household Sample Survey, reported a smoking prevalence rate of 17.2% for people anile 15 years or older [iii]. In the adult population of 27 Brazilian cities, fourteen.viii% were smokers, and the frequency was greater for men (xviii.i%) than for women (12.0%) [iv].
It is known that smoking tin can cause lung and other cancers, heart disease, stroke and many other diseases [2]. When associated with pregnancy, tobacco consumption can have even more astringent effects, potentially compromising non only maternal health, but also fetal wellness and viability [5]. In the United States, about xx% of women are smokers at the beginning of pregnancy; however, 30.ii% to 61% surrender smoking in the prenatal period [6]. Women who are able to quit tend to accept been light smokers [vii]. At that place are no national Brazilian data on the prevalence of smoking during pregnancy, nor are there estimates on smoking cessation during pregnancy; notwithstanding, a population-based study carried out in Santa Maria, southern Brazil, reported that 23% of pregnant women were smokers [eight].
Cigarettes are amidst the well-nigh often used drugs in pregnancy [nine]. A Brazilian study identified greater run a risk of smoking during pregnancy in women with a higher number of previous pregnancies and who did not undergo prenatal intendance [8].
Smoking in pregnancy is also associated with cognitive disabilities in the newborn, slower fetal growth, abortion and premature nascency [eight, ix].
The mechanisms through which smoking leads to negative effects during pregnancy accept non been fully understood. Nicotine likely plays an important role. Nicotine causes reduction in uteroplacental circulation, leading to lower maternal weight gain and in plough, negative fetal outcomes, such equally small size for gestational age, low nascence weight, short stature and compromised fetal neurological development. Additionally, cigarettes and their fume contain more than than 4000 potentially toxic substances, and the combination of these toxins in cigarette smoke may be the chief cistron responsible for health damage [ten].
Other important negative furnishings of smoking are seen in pregnancy and the postpartum period. During pregnancy, smoking compromises local and systemic immune responses, which in turn may be associated with agin pregnancy outcomes [11]. Postpartum, cigarettes can crusade early on abeyance of breastfeeding and consequences for child wellness and development [12].
Although in that location are endless studies in the literature confirming the relationship between smoking and low birth weight, they have non considered the dose–response consequence of smoking on low birth weight [5, 8, 13]. In view of the loftier prevalence of smoking during pregnancy in Brazil, the loftier likelihood of adverse perinatal consequences and the difficulty of quitting, this study aimed to clarify the effect of different intensities of smoking on birth weight of the newborn.
Methods
This cantankerous-sectional study evaluated smoking in pregnant women from 13 small towns belonging to the "Colegiado Pólo Cuesta", a health network in Botucatu, a medium-sized city (140,000 inhabitants) in southeastern São Paulo, Brazil.
In Botucatu, the Public Health Service operates eighteen primary care units that provide bones wellness care and other health services. Childbirth intendance is provided by specialty obstetrics and neonatology services at a university referral hospital, which has twoscore beds for pregnant/puerperal women, 24 beds for newborns, 30 beds in the Intensive Care Unit of measurement (ICU) for adults and 15 beds for neonates.
In addition to public health services, private health insurance and services are likewise bachelor in Botucatu. In that location is 1 private maternity infirmary with 16 beds for pregnant/puerperal women, six beds for newborns and an boosted 10 beds in the ICU for both adults and neonates.
Systematic sampling was used in this study: all pregnant women admitted to give birth at either of the two maternity hospitals during the written report menstruum from January 1 to June xxx, 2012, were considered eligible for the written report. Only women meaning with a single fetus were included in the study. A total of 1404 pregnant/puerperal women met those conditions. Seven women refused to participate and 84 were discharged before information collection was possible; thus, the final sample consisted of 1313 pregnant/puerperal women, representing 93.v% of the eligible report population.
All subjects gave informed written consent prior to their participation in the study, in accordance with established principles of inquiry ethics. The study was approved past the Enquiry Ideals Committee of Botucatu Medical School (blessing number 004/2013).
The variable nether investigation was smoking during pregnancy (classified equally: no; yeah, from ane to v cigarettes per day; yeah, from 6 to 10 cigarettes per day and yeah, from eleven to twoscore cigarettes per twenty-four hours. With this option, the study aimed to analyze the effect of different intensities of smoking on nascency weight of the newborn compared to the birth weight of newborns from nonsmoker pregnant women. Smoking during pregnancy data were obtained from medical records (56.3%) and when they were non recorded, they were obtained during interviews (43.seven%) with the puerperal women in the hospital where the birth took place. In the interviews, the question asked was: "Do/Did you smoke during gestation period? If and then, how many cigarettes do/did you usually fume per mean solar day". For both forms of data drove, women who reported having smoked merely equally they did not know they were meaning or for a short period of gestation (n = 6) were classified as non-smoking. Women classified as smokers during gestation were those who reported having maintained this addiction throughout pregnancy.
Information were also nerveless on potentially confounding sociodemographic, medical and behavioral variables. Sociodemographic variables included: historic period (classified as ≤19 years, twenty–34 years, ≥ 35 years); teaching (≤ 8 years, ix–11 years, ≥ 12 years); paid employment (yes/no); and presence of a partner (yes/no). Medical variables included information on obstetrical history, namely: first pregnancy, yes/no; the interval betwixt deliveries, only for multiparous women (≤ ii years, 3–v years, ≥ 6 years); and pregestational overweight or obesity (based on body mass index and classified according to the Constitute of Medicine) [14] (yes/no). The quality of prenatal care was also investigated using the variables: place of care (public service facility, private service facility); number of medical visits (observing that seven visits are proposed as minimum by the Brazilian Ministry of Health), (< 7 visits, 7–xiv visits, ≥ 15 visits, subsequently classified into < 7 visits, ≥ seven visits); participation in a prenatal educational grouping (yeah/no); previous advice regarding warning signs in pregnancy (yep/no); and use of both folic acrid (equally of the first prenatal visit) and fe sulfate (every bit of the 20th calendar week of gestation)(yep/no). Finally, the presence of whatever bug during gestation (yes/no) was investigated, including emotional bug; alcoholic beverage consumption; use of illegal drugs; anemia; high claret pressure, pre-eclampsia, eclampsia, or hemolysis, elevated liver enzymes, depression platelet count (HELLP) syndrome; diabetes; hyperemesis; hemorrhage, bleeding, or threatened ballgame; and infection, such as syphilis, urinary tract infection, toxoplasmosis, human immunodeficiency virus (HIV), or hepatitis.
Infant data were also collected to evaluate furnishings. The consequence variable was birth weight (g). Given the close relationship between birth weight and gestational age, the furnishings of smoking on term and premature newborns were studied separately [xv, 16]; therefore, information were likewise nerveless on the nascency condition (preterm, full-term) for stratification.
Only as for the information on smoking, all these other information were obtained from maternal or infant medical records (including prenatal care cards and records from the delivery room or the plant nursery) during hospital admission for commitment. Data that were non recorded were obtained past interview with the pregnant/puerperal women, likewise during infirmary admission.
All information were nerveless by authorized wellness service professionals, under the supervision of a doctoral educatee in public health who was responsible for quality control. The data were input to a database and checked for consistency before statistical assay.
The data analyses were performed in ii phases. Offset, the effect of each possible confounding variable on newborn weight was estimated using a univariate gamma response model (rough assay); variables with p < 0.twenty were called every bit potential confounders for inclusion in the following multivariate analysis. In the second stage, the smoking issue, corrected for the result of the identified confounders, was estimated using a gamma response regression model (adjusted analysis). This model was selected for its ability to simultaneously estimate the main issue and correct for the outcome of potential confounders (following the asymmetric probability distribution of the outcome). Relationships were considered meaning if p < 0.05. All analyses were performed using the Statistical Package for the Social Sciences SPSS v 20.0.
Results
Nearly study participants were aged twenty–34 years and had 8 to 11 years of school attendance. Considering premature and term newborns, nearly mothers lived with a partner respectively), employed (49.7% and 56.v%, respectively), were multiparous (57.1% and 62.0%, respectively) and prenatal follow-up had been provided by public services (75.1% and 70.4%, respectively). Amidst the women who had preterm delivery (n = 189), 59.3% had attended ≤7 medical visits; amongst those who delivered at term (northward = 1124), 73.two% had attended 8–14 prenatal visits.
The prevalence of smoking was 18.0% among mothers of premature infants and 12.six% among mothers of term infants. In both groups, the median of the number of cigarettes smoked per mean solar day ranged from ane to xl cigarettes/day. The preterm birth rate was fourteen.iv%. Median birth weight was 2410 g and 3250 g for premature and full-term infants, respectively (Table 1).
The relationship between potential confounders and weight of premature infants is besides shown in Table 2. Attendance at ≥seven prenatal medical visits; participation in a prenatal educational group; presence of emotional problems; high claret pressure level, pre-eclampsia, eclampsia or HELLP syndrome; hyperemesis; hemorrhage, haemorrhage or threatened abortion; and infection during pregnancy were all identified equally possible confounders (p < 0.twenty).
The relationship between smoking during pregnancy and birth weight of premature infants, adjusted for potential confounders (adjusted analysis), is shown in Tabular array iii. Again, no significant difference in birth weight was constitute in relation to smoking.
In contrast, in full-term infants the following potential confounding factors (p < 0.20) were identified: presence of a partner; first pregnancy; interval between deliveries; omnipresence at ≥7 prenatal visits; emotional bug during pregnancy; age at delivery; illegal drug use; anemia; high blood pressure, pre-eclampsia, eclampsia or HELLP syndrome; hyperemesis; and infection during pregnancy (Table 4).
The independent upshot of smoking intensity on birth weight was estimated correcting for the potential confounding variables in the adapted regression model (Table 5). Newborn weight decreased equally the category of number of cigarettes per day increased, with a meaning reduction at the 6 to 10 cigarettes: when mothers smoked 6 to 10 cigarettes per twenty-four hour period, baby weight was 320.41 g (CI 95% = − 535.51 to − 105,32) lower than that of infants born to nonsmoker mothers; when mothers smoked 10 to 40 cigarettes per day, infant weight was 435.01 g (CI 95% = − 733.16 to − 136,87) lower than that of infants born to nonsmoker mothers. When the female parent smoked during pregnancy upward to five cigarettes per 24-hour interval at that place was no outcome on birth weight (p = 0.715).
Discussion
This report evaluated the prevalence of smoking and the human relationship between birth weight and smoking intensity in a population of women who gave nascence in a medium-sized city in southeastern Brazil. The affect of tabagism was evaluated using a cathegorized pattern instead of a continuous variable, because of the irregular distribution of the variable and loftier proportion of zeros (nonsmoker mothers). That procedure was performed then that a dilution of the smoking event could exist avoided (hateful result), and the bear upon of different loads of maternal smoking could exist detected: one to 5 cigarretes per day or light smokers, 6 to 10 or medium smokers and 11 to forty or heavier smokers.
Analysis of the premature babe information showed no statistically significant differences between the birth weight of infants born to smoking and nonsmoking pregnant women. In contrast, the analysis of total-term infants revealed a negative, dose–response upshot of smoking on newborn weight. Compared with infants born to nonsmoking mothers, mean birth weight was 320 g lower in newborns whose mothers smoked 6–x cigarettes per 24-hour interval and 435 thou lower in newborns whose mothers smoked 11–40 cigarettes per day during pregnancy. This effect was observed fifty-fifty after correction for identified potential confounders, such as maternal historic period, presence of a partner, parity, interval between deliveries, number of prenatal medical visits, emotional bug in pregnancy, illegal drug use, anemia, high blood pressure, hyperemesis, gestational age and infection during pregnancy. Interestingly, no statistically pregnant differences were institute in mean birth weight when mothers smoked one–five cigarettes per 24-hour interval.
An important consideration is that the accurateness of the data on smoking and the number of cigarettes smoked per day during pregnancy may limit the validity of the report findings. It is known that the number of cigarettes smoked per twenty-four hour period tin can vary throughout pregnancy [17], and this was not addressed in the cantankerous-sectional design of the nowadays report, which relied on self-reporting at the fourth dimension of delivery or medical records. Also, women who reported having quit the habit just at the commencement of gestation were considered as nonsmokers, and the passive exposure to tobacco smoke (non investigated) was not considered, which could issue in some underestimation of the smoking event on nascence weight. Nevertheless, an of import negative effect was observed.
The information are representative of a single place in the southeastern region of Brazil. The prevalence of smoking in the significant women that was found in our study (overall prevalence of thirteen.4%) corroborates the importance of understanding its effects. The smoking prevalence among meaning women in Botucatu was lower than that in not-pregnant developed women in São Paulo capital city (16.8%) and higher to the average value reported in other Brazilian capitals (12%), the but population information available for comparisons [4]. Furthermore, smoking effects are mainly a result of biological processes, and that fact as well may support the generalization of our findings. Nevertheless, information technology is likely that in similar contexts and populations (heart-income countries with good availability of prenatal care), tobacco employ during pregnancy will negatively affect term newborn weight to a similar extension as it did in the present report.
Virtually 40% of pregnant women are estimated to quit smoking spontaneously, primarily out of concerns for fetal health but also, out of business organization for their own. Others may be encouraged to quit smoking, through concerted counseling most the risks of smoking to fetus and female parent that begins at the initiation of prenatal intendance [18]. On the whole, pregnant women are receptive to educational measures and wellness promotion [17] and are more likely to consider smoking cessation in the context of the frequent contact with wellness professionals during prenatal intendance [9]. Accordingly, the prenatal protocol of the Brazilian Health Ministry [16] instructs that smoking pregnant women exist identified in prenatal medical visits, advised to quit and offered support to achieve this goal. As such, the findings of the report population are worrying. It is likely that not all meaning women were accordingly counseled during their medical visits. The high prevalence of smoking in the report population shows that actions to accost prevention of tobacco use in full general and, particularly, during prenatal intendance, have been inadequate in the written report region.
Despite the need for smoking abeyance, information technology may exist more challenging to attain information technology during pregnancy, especially considering that a powerful psychoactive drug, nicotine, causes chemical addiction to smoking [xix]. Nicotine replacement therapy has been effective in helping the addicted population to quit smoking [xx] and thus, reduces damage from smoking; however, its use during pregnancy is controversial [21]. Questions remain most long-term furnishings and the safety of nicotine replacement therapy during pregnancy and the postpartum flow [13, 21, 22].
From the perspective of practical advice for meaning women unable to quit smoking, the study findings support the recommendation of less than six cigarettes a mean solar day to minimize the negative effects of smoking on newborn weight; notwithstanding, this must be validated with farther studies evaluating the effects of reduced tobacco use on birth weight and on other outcomes, such as prematurity, stillbirth and sudden infant death syndrome.
Conclusions
The study showed that smoking during pregnancy is associated with lower birth weight in full-term infants. Smoking intensity is as well of import. The written report plant a dose–response that was pregnant as of the 6 to ten cigarette-per-day category.
The high reported prevalence of smoking amid women during pregnancy shows that actions to promote and support smoking abeyance during pregnancy are definitely necessary in the study region. Smoke-free policies, both at a national level and globally, must remain strict, specially when related to recommendations of complete smoking cessation during pregnancy. If, nevertheless, the goal of total abstinence proves impossible, there is still an opportunity to minimize the negative furnishings of smoking during pregnancy on birth weight by reducing as much as possible the number of cigarettes smoked per day.
Abbreviations
- HELLP:
-
Hemolysis, elevated liver enzymes, low platelet count
- HIV:
-
Human being immunodeficiency virus
- ICU:
-
Intensive Care Unit of measurement
- SPSS:
-
Statistical package for the social sciences
References
-
World Health Organisation. WHO report on the global tobacco epidemic, 2011. Warning near the dangers of tobacco. Geneva: World Wellness Organization; 2011. Available from: http://whqlibdoc.who.int/publications/2011/9789240687813_eng.pdf. [cited 2015 Mar 20].
-
Centers for Disease Control and Prevention (CDC). Current cigarette smoking amidst adults – United States, 2011. Morb Mortal Wkly Rep. 2012;61(44):889–94.
-
Instituto Nacional do Câncer. Organização Pan-Americana de Saúde: Pesquisa especial de tabagismo. PETab. Relatório Brasil. Rio de Janeiro: Instituto Nacional do Câncer; 2011. Available from: bvsms.saude.gov.br/bvs/publicacoes/pesquisa_especial_tabagismo_petab.pdf
-
Ministério da Saúde, Secretaria de Vigilância em Saúde. Vigitel Brasil 2011: Vigilância de fatores de risco e proteção para doenças crônicas por inquérito telefônico. BrasÃlia (DF): Ministério da Saúde; 2012.
-
Murin S, Rafii R, Bilello K. Smoking and smoking abeyance in pregnancy. Clin Chest Med. 2011;32:75–91.
-
Tong VT, Jones JR, Dietz PM, D'Angelo D, Bombard JM. Trends in smoking earlier, during, and later on pregnancy - pregnancy risk assessment monitoring system (PRAMS) United States, 31 sites, 2000-2005. MMWR Surveill Summ. 2009;58:1–29.
-
Stotts AL, Groff JY, Velasquez MM, Benjamin-Garner R, Green C, Carbonari JP, et al. Ultrasound feedback and motivational interviewing targeting smoking cessation in the second and third trimesters of pregnancy. Nicotine Tob Res. 2009;xi:961–8.
-
Galão AO, Soder SA, Gerhardt K, Faertes TH, Krüger MS, Pereira DF, et al. Efeitos do fumo materno durante a gestação due east complicações perinatais. Rev HCPA. 2009;29:218–24.
-
Motta GCP, Echer IC, Lucena AF. Fatores associados ao tabagismo na gestação. Rev Latino-Am Enfermagem. 2010;18:08 telas.
-
Ontario Medical Association (OMA). Rethinking cease-smoking medications: handling myths and medical realities. Ontario Med Rev. 2008;75(1):22–34. Bachelor from: http://youcanmakeithappen.ca/wp-content/uploads/2011/08/2008RethinkingStop-SmokingMedications.pdf. [cited 2015 Mar xx].
-
Prins JR, Hylkema MN, JJHM E, Huitema South, Dekkema GJ, Dijkstra FE, et al. Smoking during pregnancy influences the maternal immune response in mice and humans. Am J Obstet Gynecol. 2012;207:76.e1–14.
-
Del Ciampo LA, Ricco RG, Ferraz IS, Daneluzzi JC, Martinelli Junior CE. Prevalence of smoking and alcohol consumption among mothers of infants under half-dozen months of age. Rev Paul Pediatr. 2009;27:361–5.
-
Jaddoe VW, Troe EJ, Hofman A, Mackenbach JP, Moll HA, Steegers EA, et al. Active and passive maternal smoking during pregnancy and the risks of depression birthweight and preterm nativity: the generation R report. Paediatr Perinat Epidemiol. 2008;22:162–71.
-
Institute of Medicine. Weight proceeds during pregnancy: reexamining the guidelines. Washington: Institute of Medicine; 2009. Available from: http://www.nationalacademies.org/hmd/~/media/Files/Report%20Files/2009/Weight-Proceeds-During-Pregnancy-Reexamining-the-Guidelines/Report%20Brief%xx-%20Weight%20Gain%20During%20Pregnancy.pdf. [cited 2016 Mar xx].
-
Barros FC, Victora CG, Matijasevich A, Santos IS, Horta BL, Silveira MF, et al. Preterm births, depression birth weight, and intrauterine growth restriction in 3 birth cohorts in southern Brasil: 1982, 1993 and 2004. Cad Saúde Pública. 2008;24(Suppl 3):S390–8.
-
World Health System. Guidelines on optimal feeding of low birth-weight infants in low- and heart-income countries. Geneva: World Health Organization; 2011. Bachelor from: http://www.who.int/maternal_child_adolescent/documents/9789241548366.pdf?ua=1. [cited 2015 Mar 20].
-
da Saúde One thousand. Secretaria de Atenção a Saúde. Cadernos de Atenção Básica: Atenção ao Pré-natal de Baixo Risco. Ministério da Saúde: BrasÃlia (DF); 2012.
-
Reichert J, Araújo AJ, Gonçalves CMC, Godoy I, Chatkin JM, Sales MPU, et al. Diretrizes para cessação practise tabagismo. J Bras Pneumol. 2008;34:845–80.
-
Grief SN. Nicotine dependence: health consequences, smoking cessation therapies, and pharmacotherapy. Prim Care Clin Office Pract. 2011;38:23–39.
-
Beard E, Aveyard P, Dark-brown J, Due west R. Assessing the association between the use of NRT for smoking reduction and attempts to quit smoking using propensity score matching. Drug Alcohol Depend. 2012;126:354–61.
-
Brose LS, McEwen A, West R. Association between nicotine replacement therapy apply in pregnancy and smoking cessation. Drug Booze Depend. 2013;128:15–9.
-
Bruin JE, Gerstein HC, Holloway Ac. Long-term consequences of fetal and neonatal nicotine exposure: a disquisitional review. Toxicol Sci. 2010;116:364–74.
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The authors gratefully acknowledge the São Paulo Research Foundation for funding this research.
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All authors have made substantial contributions to the study, and all endorsed the data and conclusions. MCK contributed to conception and design of the study, data conquering, and analysis and interpretation of data. APPC contributed to formulation and design of the report, information acquisition, and analysis and estimation of information; participated in writing the draft manuscript and revised information technology critically for important intellectual content, and gave concluding approving of the version to be published. APF participated in writing the typhoon manuscript and revised it critically for important intellectual content, and gave final approval of the version to be published. MBM participated in writing the draft manuscript and revised it critically for important intellectual content, and gave last approval of the version to exist published. MABLC participated in writing the typhoon manuscript and revised it critically for important intellectual content, and gave final approval of the version to be published. CMGLP participated in writing the draft manuscript and revised it critically for important intellectual content, and gave terminal approving of the version to exist published.
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Kataoka, Thousand.C., Carvalheira, A.P.P., Ferrari, A.P. et al. Smoking during pregnancy and harm reduction in nascence weight: a cross-exclusive study. BMC Pregnancy Childbirth 18, 67 (2018). https://doi.org/10.1186/s12884-018-1694-iv
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DOI : https://doi.org/10.1186/s12884-018-1694-four
Keywords
- Pregnancy
- Smoking
- Tobacco apply cessation
- Birth weight
Source: https://bmcpregnancychildbirth.biomedcentral.com/articles/10.1186/s12884-018-1694-4
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