Risk factors for preterm births in São Luís, Maranhão, Brazil

Preterm birth continues to be one of the main causes of neonatal morbidity and mortality. The objective of the present study was to identify risk factors for preterm birth in São Luís, Maranhão, Brazil. The sample consisted of hospital births at 10 public and private hospitals from March 1, 1997 to February 28, 1998. A total of 2,443 live births were randomly selected, excluding multiple deliveries and stillbirths. Preterm birth rate in São Luís was 12.7%. Risk factors for preterm delivery were maternal age below 18 years, family income equal to or less than one minimum wage/ month, primiparity, vaginal delivery at a public hospital, single mothers (or living without a partner), and absence of prenatal care. The following factors remained associated with preterm birth after multivariate analysis to control for confounding: maternal age below 18 years (OR = 1.9), primiparity (OR = 1.5), and failure to appear for scheduled prenatal care visits (OR = 1.5).

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EPIDEMIOLOGY AND RISK FACTORS FOR PREMATURE BIRTH

Knowledge International Journal ◽

10.35120/kij2802629m ◽

2018 ◽

Vol 28 (2) ◽

pp. 629-636

Author(s):

Anna Mihaylova ◽

Nikoleta Parahuleva ◽

Elina Petkova-Gueorguieva ◽

Stanislav Gueorguiev

Keyword(s):

Risk Factors ◽

Preterm Birth ◽

Prenatal Care ◽

Premature Birth ◽

Assisted Reproductive Technologies ◽

Preterm Births ◽

Developed Countries ◽

Reproductive Technologies ◽

Risk Indicators ◽

Etiological Factors

Premature birth is a significant medical, social and economic problem worldwide. In the 21st Century in developed countries, this problem accounts for over two thirds of neonatal deaths. In Bulgaria, statistics show that 10-12% of all pregnancies end with premature birth. Despite the number of studies in this field and the efforts made by obstetricians and gynecologists, the tendency to increase the number of preterm births has continued in the last decade. Its consequences are multiple complications who lead to a high neonatal mortality in the national and global world. Preterm birth is characterized by complex and vague etiology. A specific cause of premature birth can not be defined, but a set of risk factors is considered, divided into three main groups of etiological factors: socio-economic, medical-biological, and behavioral. Associated with preterm birth socio-economic and behavioral risk factors include poverty, unemployment, low education, poor prenatal care, harmful habits such as smoking, alcohol, drugs and other harmful substances, unhealthy family environment, severe and prolonged stress, excessive physical exercise (lifting weights), trauma (hits or violence), new pregnancies less than 6 months after previous birth, unhealthy diet and low mother BMI, etc. Essential for the preterm birth is also the medico - biological etiological factors. One of these is uterine enlargement, as the main reason for this may be the presence of: multiple pregnancies that occurred naturally or after using assisted reproductive technologies or polyhydramnios (increased amount of amniotic fluid). Other risk factors include: placenta previa, incorrect position of the fetus, myoma, uterine cervix malformations (including cerebrovascular insufficiency), preeclampsia, uterine contractions, acute infections during pregnancy (vaginal - chlamydia, trichomonas, mycoplasma , toxoplasmosis, bacterial vaginosis, viral rubella, cytomegalovirus, herpes, influenza, adenovirus infection, chronic diseases (hypertension, cardiovascular diseases, diseases of the lungs, liver or kidney anemia and etc.), genetic factors, previous premature birth, etc. These risk indicators are subject to detailed analysis in the work of a number of authors. To limit preterm births, a number of studies have been conducted to identify and identify the risk factors that are relevant to it. Identifying and recognizing their effects and impact leading to premature birth will significantly reduce the severe health, economic and social consequences as well as reduce the risk of neonatal death. In order to reduce the frequency of preterm births, adequate and specialized prenatal care is essential. They must be individually tailored for each particular case of pregnancy and take into account the complex of risk predispositions.

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Determinants of preterm birth: Pelotas, Rio Grande do Sul State, Brazil, 2004 birth cohort

Cadernos de Saúde Pública ◽

10.1590/s0102-311x2010000100019 ◽

2010 ◽

Vol 26 (1) ◽

pp. 185-194 ◽

Cited By ~ 24

Author(s):

Mariângela F. Silveira ◽

Cesar G. Victora ◽

Aluísio J. D. Barros ◽

Iná S. Santos ◽

Alicia Matijasevich ◽

...

Keyword(s):

Risk Factors ◽

Preterm Birth ◽

Birth Cohort ◽

Low Income ◽

Family Income ◽

Preterm Births ◽

Rio Grande ◽

Low Income Countries ◽

Rio Grande Do Sul ◽

Vaginal Deliveries

Prematurity is a leading cause of neonatal mortality and a global health problem that affects high, middle and low-income countries. Several factors may increase the risk of preterm birth. In this article, we test the hypothesis that different risk factors determine preterm birth in different income groups by investigating whether risk factors for preterm deliveries in the 2004 Pelotas (Rio Grande do Sul State, Brazil) birth cohort vary among those groups. A total of 4,142 women were included in the analysis. Preterm births were equally common among women who had spontaneous vaginal deliveries as for those with induced or operative births. In the multivariate analysis the factors that remained significantly associated with preterm birth were black skin color, low education, poverty, young maternal age, primiparity, previous preterm birth, inadequacy of prenatal care and reported hypertension. In the analyses repeated after stratification by family income terciles, there was no evidence of effect modification by income and no clear difference between the socioeconomic groups. No association between cesarean section and preterm delivery was found. Further studies are required to understand the causes of the epidemic of preterm births in Brazil.

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Risk Factors and Outcome of Preterm Labour in Tertiary Health Centre

Bangladesh Journal of Obstetrics & Gynaecology ◽

10.3329/bjog.v32i2.48279 ◽

2020 ◽

Vol 32 (2) ◽

pp. 90-93

Author(s):

Mst Afroza Khanum ◽

Salma Lavereen ◽

Moniruzzaman ◽

Romana

Keyword(s):

Risk Factors ◽

Risk Factor ◽

Preterm Birth ◽

Preterm Delivery ◽

Preterm Labour ◽

Health Centre ◽

Preterm Births ◽

Neonatal Morbidity ◽

Vaginal Infection ◽

History Of

Background: Currently preterm labour is one of the most challenging problems confronting the obstetricians and perinatologists. This unfortunate episode accounts for 50-75% of the perinatal mortality. Methods: A cross sectional study was conducted on 210 pregnant women with preterm labour admitted in Monno Medical College Hospital, Manikganj from June 2014 to December 2015, to study the causes and outcome of preterm birth in Tertiary health centre of Manikganj. Results: Occurence of preterm birth was 13.82%; 47.14% occured between 34-37 weeks of gestation; 33.80% occured 31-33 weeks of gestation and occurred in 28-30 weeks 19.04%. About 22% patients presenting with preterm labour had a past history of abortions and 14.3% had a history of preterm delivery. Premature rupture of membranes was found to be the most common risk factor related with preterm labour in the present pregnancy. Genitourinary tract infection was the next important risk factor of preterm labour; 24.8% (86) patients had either vaginal infection (19.5%) or urinary infection (21.4%) or both. Another important risk factor identified in this study was antepartum haemorrage which was cause in 11.4 % cases. Preterm babies commonly suffered from various complications like jaundice (32.1%), respiratory distress syndrome (22.6%), asphyxia (13.5%), sepsis, hypoglycemia and coagulopathy. Conclusion: Most of the preterm births occured between 34-37 weeks of gestation. Most common risk factors of preterm births are history of abortion and preterm delivery in previous pregnancy; PROM UTI vaginal infection, PIH and APH in correct pregnancy. Newborn jaundice, RDS and birth asphyxia are the common neonatal morbidity in preterm labour. Identifying risk factors to prevent the onset of preterm labour and advanced neonatal care unit can help decrease neonatal morbidity and mortality. Bangladesh J Obstet Gynaecol, 2017; Vol. 32(2) : 90-93

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Smoking and other pre-gestational risk factors for spontaneous preterm birth

Revista Brasileira de Saúde Materno Infantil ◽

10.1590/s1519-38292011000400006 ◽

2011 ◽

Vol 11 (4) ◽

pp. 397-403 ◽

Cited By ~ 3

Author(s):

Eugênio Grillo ◽

Paulo Fontoura Freitas

Keyword(s):

Risk Factors ◽

Body Mass Index ◽

Preterm Birth ◽

Body Mass ◽

Gestational Age ◽

Maternal Age ◽

Preterm Births ◽

Cumulative Effects ◽

Independent Effect ◽

Spontaneous Preterm Birth

OBJECTIVES: to investigate pre-gestational risk factors for spontaneous preterm birth and, the role of smoking and its cumulative effects on prematurity. METHODS: a case-control study analyzed a data set of all births occurring in a tertiary maternity hospital between April 2002 and July 2004. Spontaneous preterm births of single and live newborns without malformations were selected as cases. Controls were all the term births of live and single newborns without malformations during the same period. Three outcomes were studied: all preterm births (<37 weeks), less than 35 weeks and less than 32 weeks of gestational age. Logistic regression was used to obtain the independent effect of pre-gestational risk factors. RESULTS: maternal age of less than 20 years, low schooling, low maternal pre-gestational body mass index and smoking showed significant, independent association with spontaneous preterm birth for the three outcomes. For all these risk factors, excepting maternal smoking, odds ratios increased with decreasing gestational age at birth and this trend was significant for low maternal age and low pre-gestational body mass index. CONCLUSIONS: the cumulative effects of smoking calls for the need to encourage smoking cessation among pregnant women, especially those who are underweight and in the older age groups, because of the increased risk of delivering premature babies.

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Low birthweight and preterm birth: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982–2015

International Journal of Epidemiology ◽

10.1093/ije/dyy106 ◽

2018 ◽

Vol 48 (Supplement_1) ◽

pp. i46-i53 ◽

Cited By ~ 17

Author(s):

Mariangela F Silveira ◽

Cesar G Victora ◽

Bernardo L Horta ◽

Bruna G C da Silva ◽

Alicia Matijasevich ◽

...

Keyword(s):

Risk Factors ◽

Preterm Birth ◽

Low Income ◽

Low Birthweight ◽

Family Income ◽

Preterm Births ◽

Population Based ◽

Skin Colour ◽

Birth Cohorts ◽

Maternal Risk

Abstract Background Despite positive changes in most maternal risk factors in Brazil, previous studies did not show reductions in preterm birth and low birthweight. We analysed trends and inequalities in these outcomes over a 33-year period in a Brazilian city. Methods Four population-based birth cohort studies were carried out in the city of Pelotas in 1982, 1993, 2004 and 2015, with samples ranging from 4231 to 5914 liveborn children. Low birthweight (LBW) was defined as <2500 g, and preterm birth as less than 37 weeks of gestation. Information was collected on family income, maternal skin colour and other risk factors for low birthweight. Multivariable linear regression was used to estimate the contribution of risk factors to time trends in birthweight. Results Preterm births increased from 5.8% (1982) to 13.8% (2015), and LBW prevalence increased from 9.0% to 10.1%, being higher for boys and for children born to mothers with low income and brown or black skin colour. Mean birthweight remained stable, around 3200 g, but increased from 3058 to 3146 g in the poorest quintile and decreased from 3307 to 3227 g in the richest quintile. After adjustment for risk factors for LBW, mean birthweight was estimated to have declined by 160 g over 1982–2015 (reductions of 103 g in the poorest and 213 g in the richest quintiles). Conclusions Data from four birth cohorts show that preterm births increased markedly. Mean birthweights remained stable over a 33-year period. Increased prevalence of preterm and early term births, associated with high levels of obstetric interventions, has offset the expected improvements due to reduction in risk factors for low birthweight.

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Preterm Delivery; Who Is at Risk?

Journal of Clinical Medicine ◽

10.3390/jcm10112279 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2279

Author(s):

Dvora Kluwgant ◽

Tamar Wainstock ◽

Eyal Sheiner ◽

Gali Pariente

Keyword(s):

Risk Factors ◽

Preterm Birth ◽

Prenatal Care ◽

Recurrent Pregnancy Loss ◽

Placental Abruption ◽

Placenta Previa ◽

Population Based ◽

Perinatal Morbidity ◽

Multiple Gestations ◽

Extremely Preterm

Preterm birth (PTB) is the leading cause of perinatal morbidity and mortality. Adverse effects of preterm birth have a direct correlation with the degree of prematurity, in which infants who are born extremely preterm (24–28 weeks gestation) have the worst outcomes. We sought to determine prominent risk factors for extreme PTB and whether these factors varied between various sub-populations with known risk factors such as previous PTB and multiple gestations. A population-based retrospective cohort study was conducted. Risk factors were examined in cases of extreme PTB in the general population, as well as various sub-groups: singleton and multiple gestations, women with a previous PTB, and women with indicated or induced PTB. A total of 334,415 deliveries were included, of which 1155 (0.35%) were in the extreme PTB group. Placenta previa (OR = 5.8, 95%CI 4.14–8.34, p < 0.001), multiple gestations (OR = 7.7, 95% CI 6.58–9.04, p < 0.001), and placental abruption (OR = 20.6, 95%CI 17.00–24.96, p < 0.001) were the strongest risk factors for extreme PTB. In sub-populations (multiple gestations, women with previous PTB and indicated PTBs), risk factors included placental abruption and previa, lack of prenatal care, and recurrent pregnancy loss. Singleton extreme PTB risk factors included nulliparity, lack of prenatal care, and placental abruption. Placental abruption was the strongest risk factor for extreme preterm birth in all groups, and risk factors did not differ significantly between sub-populations.

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Magnitude of spontaneous preterm birth and its associated factors among preterm birth in NICU wards in Asella Teaching and Referral Hospital, Asella, Oromia, Ethiopia

Journal of International Medical Research ◽

10.1177/03000605211034693 ◽

2021 ◽

Vol 49 (8) ◽

pp. 030006052110346

Author(s):

Techane Sisay Tuji ◽

Addisu Dabi Wake ◽

Gezahegn Badeg Adere ◽

Aselefu Beka Wedajo ◽

Batu Dekeba Obole ◽

...

Keyword(s):

Risk Factors ◽

Preterm Birth ◽

Healthcare Providers ◽

Preterm Births ◽

Cross Sectional Study ◽

Spontaneous Preterm Birth ◽

Related Factors ◽

Cross Sectional ◽

Bivariate Logistic Regression ◽

Associated Risk Factors

Objective To assess the prevalence of spontaneous preterm births and to identify the associated risk factors. Methods This single-centre cross-sectional study enrolled women that experienced a preterm birth as registered on the neonatal log-book between 30 December 2019 and 30 December 2020. A pre-tested structured checklist was used to collect data (sociodemographic characteristics; obstetric-related factors; medical history; and pregnancy-related factors). Bivariate logistic regression analyses were applied to identify factors associated with spontaneous preterm birth. A multivariate model identified significant independent risk factors. Results A total of 310 patients participated in the study. The prevalence of spontaneous preterm birth in this population was 67.1% (208 of 310; 95% confidence interval [CI] 61.5, 71.9). Patients without a partner (adjusted odds ratio [AOR] = 1.470, 95% CI 1.23, 4.42), patients residing in a rural area (AOR = 2.51, 95% CI 1.123, 5.513) and those with a history of PIH during their current pregnancy (AOR = 0.104, 95% CI 0.053, 0.014) were significantly more likely to have a spontaneous preterm birth. Conclusion The prevalence of spontaneous preterm birth in in this study was high. Healthcare providers and all stakeholders should focus on screening pregnant women at the risk of spontaneous preterm birth.

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Impact of smoking and fetal gender on preterm delivery

Journal of Developmental Origins of Health and Disease ◽

10.1017/s2040174420000999 ◽

2020 ◽

pp. 1-6

Author(s):

Veronika Günther ◽

Ibrahim Alkatout ◽

Alexandra Stein ◽

Nicolai Maass ◽

Alexander Strauss ◽

...

Keyword(s):

Risk Factors ◽

Preterm Birth ◽

Preterm Delivery ◽

Preterm Infants ◽

Preterm Births ◽

World Health ◽

Smoking During Pregnancy ◽

Fetal Gender ◽

Extremely Preterm ◽

Heavy Smokers

Abstract According to the World Health Organization, smoking is the most important risk factor for adverse pregnancy outcomes in industrialized nations. We aimed to establish how fetal gender and smoking interact with regard to perinatal outcomes, especially preterm delivery. Data from 220,339 singleton pregnancies, obtained from the German Perinatal Survey in Schleswig-Holstein and registered between 2004 and 2017 were analyzed in regard to smoking behavior, fetal gender, and preterm delivery. The rate of preterm births was directly proportional to the women’s consumption of nicotine. The rate of preterm deliveries was 6.8% among nonsmokers, and 13.2% in women who were very heavy smokers (≥22 cigarettes/day). Very heavy smoking (≥22 cigarettes/day) had a marked impact on extremely preterm births (<28 weeks of gestation) and very preterm births (28–31 weeks of gestation). Preterm births increased by 1.2% from heavy smokers to very heavy smokers; the differences between the other groups ranged between 0.1% and 0.4%. Fetal gender also had an impact on preterm birth: male infants were predominant in nearly all groups of women who delivered preterm infants. Smoking during pregnancy and male gender are both risk factors for preterm delivery. Fetal gender should be given greater attention as one of the several risk factors of preterm birth. Due to the high rate of morbidity among preterm infants and enormous costs for the healthcare system, women should be encouraged to cease or at least reduce smoking during pregnancy.

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Association between maternal gestational weight gain and preterm birth according to body mass index and maternal age in Quzhou, China

Scientific Reports ◽

10.1038/s41598-020-72949-w ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Ying Hu ◽

Qi Wu ◽

Luyang Han ◽

Yuqing Zou ◽

Die Hong ◽

...

Keyword(s):

Body Mass Index ◽

Weight Gain ◽

Preterm Birth ◽

Gestational Weight Gain ◽

Body Mass ◽

Maternal Age ◽

Preterm Births ◽

Normal Weight ◽

Live Births ◽

Gestational Weight

Abstract The aim of this study is to investigate the association between maternal gestational weight gain (GWG) and preterm birth according to pre-pregnancy body mass index (BMI) and maternal age. We did a cohort, hospital-based study in Quzhou, South China, from 1 Jan 2018 to 30 June 2019. We selected 4274 singleton live births in our analysis, 315 (7.4%) of which were preterm births. In the overall population, excess GWG was significantly associated with a decreased risk of preterm birth compared with adequate GWG (adjusted OR 0.81 [95% CI 0.72–0.91]), and the risk varied by increasing maternal age and pre-pregnancy BMI. Interestingly, underweight women who older than 35 years with excess GWG had significantly increased odds of preterm birth compared with adequate GWG in underweight women aged 20–29 years (2.26 [1.06–4.85]) and normal weight women older than 35 years (2.23 [1.13–4.39]). Additionally, low GWG was positively and significantly associated with preterm birth overall (1.92 [1.47–2.50]). Among normal weight women category, compared with adequate GWG women aged 20–29 years did, those older than 20 years with low GWG, had significantly higher odds of preterm birth, which increased with maternal age (1.80 [1.16–2.79] in 20–29 years, 2.19 [1.23–3.91] in 30–34 years, 3.30 [1.68–6.46] in ≫ 35 years). In conclusion, maternal GWG was significantly associated with the risk of preterm birth, but the risk varied by pre-pregnancy BMI and maternal age.

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