Changes in perinatal health in two birth cohorts (1997/1998 and 2010) in São Luís, Maranhão State, Brazil

Birthweight trends and their explanatory factors in Hungary between 1999 and 2018: an analysis of the Hungarian Tauffer registry

BACKGROUND

The increasing birthweight trend stopped and even reversed in several high income countries in the last 20 years, however the reason for these changes is not well characterized. We aimed to describe birthweight trends of term deliveries in Hungary between 1999 and 2018 and to investigate potential maternal and foetal variables that could drive these changes.

METHODS

We analysed data from the Hungarian Tauffer registry, a compulsory anonymized data collection of each delivery. We included all singleton term deliveries in 1999-2018 (n = 1,591,932). We modelled birthweight trends separately in 1999-2008 and 2008-2018 in hierarchical multiple linear regression models adjusted for calendar year, newborn sex, maternal age, gestational age at delivery, and other important determinants.

RESULTS

Median birthweights increased from 3250/3400 g (girl/boy) to 3300/3440 g from 1999 to 2008 and decreased to 3260/3400 g in 2018. When we adjusted for gestational age at delivery the increase in the first period became more pronounced (5.4 g/year). During the second period, similar adjustment substantially decreased the rate of decline from 2.5 to 1.4 g/year. Further adjustment for maternal age halved the rate of increase to 2.4 g/year in the first period. During the second period, adjustment for maternal age had little effect on the estimate.

CONCLUSIONS

Our findings of an increasing birthweight trend (mostly related to the aging of the mothers) in 1999-2008 may forecast an increased risk of cardiometabolic diseases in offsprings born in this period. In contrast, the decreasing birthweight trends after 2008 may reflect some beneficial effects on perinatal morbidity. However, the long-term effect cannot be predicted, as the trend is mostly explained by the shorter pregnancies.

National data linkage assessment of live births and deaths in Mexico: Estimating under-five mortality rate ratios for vulnerable newborns and trends from 2008 to 2019

BACKGROUND

Linked datasets that enable longitudinal assessments are scarce in low and middle-income countries.

OBJECTIVES

We aimed to assess the linkage of administrative databases of live births and under-five child deaths to explore mortality and trends for preterm, small (SGA) and large for gestational age (LGA) in Mexico.

METHODS

We linked individual-level datasets collected by National statistics from 2008 to 2019. Linkage was performed based on agreement on birthday, sex, residential address. We used the Centre for Data and Knowledge Integration for Health software to identify the best candidate pairs based on similarity. Accuracy was assessed by calculating the area under the receiver operating characteristic curve. We evaluated completeness by comparing the number of linked records with reported deaths. We described the percentage of linked records by baseline characteristics to identify potential bias. Using the linked dataset, we calculated mortality rate ratios (RR) in neonatal, infants, and children under-five according to gestational age, birthweight, and size.

RESULTS

For the period 2008-2019, a total of 24,955,172 live births and 321,165 under-five deaths were available for linkage. We excluded 1,539,046 records (6.2%) with missing or implausible values. We succesfully linked 231,765 deaths (72.2%: range 57.1% in 2009 and 84.3% in 2011). The rate of neonatal mortality was higher for preterm compared with term (RR 3.83, 95% confidence interval, CI 3.78, 3.88) and for SGA compared with appropriate for gestational age (AGA) (RR 1.22 95% CI, 1.19, 1.24). Births at <28 weeks had the highest mortality (RR 35.92, 95%CI, 34.97, 36.88). LGA had no additional risk vs AGA among children under five (RR 0.92, 95%CI, 0.90, 0.93).

CONCLUSIONS

We demonstrated the utility of linked data to understand neonatal vulnerability and child mortality. We created a linked dataset that would be a valuable resource for future population-based research.

Association between violence and depression during pregnancy with perinatal outcomes: a moderated mediation analysis

OBJECTIVE

To assess the direct, indirect, and total effects of violence during pregnancy on perinatal outcomes, and to evaluate the effect of violence as a moderator of the mediated relationship of depression with perinatal outcomes.

METHODS

Data was collected from the prenatal study and follow-ups of the BRISA cohort, São Luís, Maranhão, Brazil. The perinatal outcomes investigated were: birth weight (BW), intrauterine growth restriction (IUGR) and gestational age (GA). Violence against women was evaluated using the World Health Organization Violence against Women instrument (Violence during pregnancy - regardless of the type of violence; Physical violence during pregnancy; Psychological violence during pregnancy). Depressive symptoms during pregnancy were evaluated as a mediating variable. Moderated mediation analysis was performed to estimate the effects of violence and depression on perinatal outcomes.

RESULTS

Three types of violence analyzed by depression had an indirect effect in BW and GA. None of the types of violence showed an association with IUGR. All types of violence analyzed showed a moderated mediation effect with BW and GA. Only among women who experienced violence were birth weight and gestational age lower the higher the values of depressive symptoms.

CONCLUSION

Violence and depression are only associated with lower BW and GA when they occur simultaneously.

Early weaning and family characteristics are associated with greater sodium intake in children between 13 and 35 months: BRISA birth cohort

Children are consuming less healthy foods, and this eating behaviour exposes the child to greater Na intake. The association between family, maternal and child characteristics with Na intake by children aged 13-35 months was evaluated. A study carried out with retrospective data on 1,185 children from the Brisa cohort. The children's dietary Na intake was assessed by a 24-h diet recall survey. Values ≥ 1200 mg were considered excessive intake. The association between Na intake and independent variables was assessed by a three-level logistic hierarchical regression model. Variables with P-value < 0·05 were retained in the model. Most children were male (51·2 %), eutrophic (63·2 %) and not exclusively breast-feeding (EBF) for 6 months (58·4 %). The average Na intake was 925 mg (±410·4). The prevalence of excessive Na intake was 18·5 % and was associated with the variables children of younger mothers (< 20 years old OR = 4·04, 95 % CI 1·64, 9·99; ≥ 20 to < 35 years old OR = 2·48, 95 % CI 1·10, 5·63), having four or more children (OR = 2·51, 95 % CI 1·29, 4·89), lower family income (≥ 1 and < 3 minimum wages OR = 0·60, 95 % CI 0·39, 0·93; ≥ 3 minimum wages OR = 0·50, 95 % CI 0·30, 0·82) and not being EBF until 6 months (OR = 1·64, 95 % CI 1·14, 2·34). The average Na intake of children was higher than the recommendation for adequate intake, pointing to a high consumption of this micronutrient in the first years of life. Excessive Na intake seems to be linked to unfavourable socio-economic conditions. Avoiding early weaning is the only possible intervention in this scenario.

Cesarean section and body mass index in children: is there a causal effect?

Obesity is considered a global public health problem. Cesarean section has been associated with high body mass index (BMI) and increased obesity throughout life. However, this association has been challenged by some studies. This study aims to assess the causal effect of cesarean section on the BMI of children aged 1-3 years. This is a cohort study of 2,181 children aged 1-3 years, born in 2010, obtained from the BRISA Birth Cohort, in São Luís, state of Maranhão, Brazil. Sociodemographic variables, maternal characteristics, type of childbirth, morbidity, anthropometric measurements, and BMI were assessed. Marginal structural models with a counterfactual approach were used to check the causal effect of the type of childbirth on obesity, weighted by the inverse probability of selection and exposure. Out of the 2,181 children assessed (52% female), 50.6% were born by cesarean section, 5.9% of the newborn infants were large for gestational age, and 10.7% of them had excess weight. No causal effect of cesarean section on BMI was observed (coefficient = -0.004; 95%CI: -0.136; 0.127; p = 0.948). Cesarean section did not have a causal effect on the BMI of children aged 1-3 years.

Factors associated with perinatal mortality in a Brazilian Northeastern capital

This study investigated factors associated with perinatal mortality in São Luís, Maranhão, Northeastern Brazil. Data on perinatal mortality were obtained from the BRISA birth cohort and from the Mortality Information System, including records of 5,236 births, 70 of which referred to fetal deaths and 36 to early neonatal deaths. Factors associated with mortality were investigated using a hierarchical logistic regression model, resulting in a perinatal mortality coefficient equal to 20.2 per thousand births. Mothers with low education level and without a partner were associated with an increased risk of perinatal death. Moreover, children of mothers who did not have at least six antenatal appointments and with multiple pregnancies (OR= 9.15; 95%CI:4.08-20.53) were more likely to have perinatal death. Perinatal death was also associated with the presence of congenital malformations (OR= 4.13; 95%CI:1.23-13.82), preterm birth (OR= 3.36; 95%CI:1.56-7.22), and low birth weight (OR=11.87; 95%CI:5.46-25.82). In turn, families headed by other family members (OR= 0.29; 95%CI: 0.12 - 0.67) comprised a protective factor for such condition. Thus, the results indicate an association between perinatal mortality and social vulnerability, non-compliance with the recommended number of prenatal appointments, congenital malformations, preterm birth, and low birthweight.

Adverse pregnancy outcomes and occlusal traits in the primary dentition: A prospective cohort (BRISA)

OBJECTIVES

This study aimed to analyse the relationship between adverse pregnancy outcomes (APO) and occlusal traits in the primary dentition, checking for different mediation paths.

SETTING AND SAMPLE POPULATION

Children evaluated at birth (T1), between 12 and 24 months (T2), and between 24 and 36 months (T3) were included. Two hundred and seventeen children who participated in T1 and T2 were randomly selected to perform the occlusion examination.

MATERIALS AND METHODS

This is a prospective cohort study (BRISA). The theoretical model was tested by structural equation modelling (SEM), estimating standardized coefficients (Coeff.) (α = 0.05). The primary exposure was APO-a latent variable manifested from three health problems at birth: low birthweight (LBW), pre-term birth (PTB) and intrauterine growth restriction (IUGR), evaluated in T1. The outcomes were four different occlusal traits assessed in T3: overjet, anterior and posterior crossbite, and crowding. Each outcome's direct and indirect effects were tested, mediated by growth, breathing, breastfeeding, and pacifier use.

RESULTS

There was no direct association between APO and any of the outcomes: overjet (Coeff. = -0.163, P = .241), anterior crossbite (Coeff. = -0.696, P = .065), posterior crossbite (Coeff. = -0.087, P = .589) and crowding (Coeff. = 0.400, P = .423). The indirect (total and specifics) effects tested also showed no association (P > .05). However, APO was associated with lower child growth in all models; breastfeeding was associated with higher child growth in all models, and pacifier use was associated with overjet (Coeff. = 0.184, P < .001) and posterior crossbite (Coeff. = 0.373, P = .011).

CONCLUSION

APO was not a risk factor for overjet, crossbite and crowding in an early stage of the primary dentition by direct and indirect pathways. However, growth has been lower in children with APO and higher in children breastfed. Also, the harmful effects of using a pacifier in dental occlusion are highlighted.

Ocupação materna e duração do aleitamento materno exclusivo: resultados de uma coorte de nascimento em São Luís, Maranhão, Brasil

Nas investigações dos determinantes da duração do aleitamento materno exclusivo (AME), a variável trabalho materno remunerado é quase sempre dicotomizada em não e sim. Este estudo analisa possíveis associações entre características da ocupação materna e menor duração do AME. Foi realizado um estudo de coorte em uma amostra sistemática de nascimentos do Município de São Luís (Maranhão, Brasil) em 2010. As exposições tipo de ocupação materna, números de dias trabalhados/semana e de horas trabalhadas/dia, trabalha em pé a maior parte do tempo e levanta objetos pesados nesse trabalho foram coletadas com 5.166 mães de nascidos vivos. A amostra final desse estudo teve 3.268 observações. Foi utilizada análise de sobrevida para testar associações entre as exposições e os desfechos AME até 4 meses (AME4) e AME até 6 meses (AME6). Não ter trabalho remunerado foi a categoria de referência. Regressões ajustadas de Cox mostraram que mães com ocupações manuais semiespecializadas (intervalo de 95% de confiança, IC95%: 1,02-1,58 para AME4 e IC95%: 1,11-1,56 para AME6) e mães que trabalhavam 8 ou mais horas diárias (IC95%: 1,01-1,36 para AME4 e IC95%: 1,11-1,41 para AME6) mais frequentemente interromperam AME. Mães com ocupações em funções de escritório (IC95%: 1,07-1,46), que trabalhavam 4-5 dias (IC95%: 1,01-1,36) ou 6-7 dias/semana (IC95%: 1,09-1,40) e por 5-7 horas (IC95%: 1,03-1,43) também praticaram menos AME6. Trabalhar (IC95%: 1,08-1,40) ou não (IC95%: 1,03-1,34) em pé a maior parte do tempo e levantar (IC95%: 1,07-1,56) ou não (IC95%: 1,06-1,33) objetos pesados no trabalho diminuíram a duração de AME6. Tipos de ocupação e de jornada de trabalho interferiram mais frequentemente na duração de AME6.

Evolution of care during pregnancy and childbirth in the extreme south of Brazil

OBJECTIVES

To describe the evolution of care during pregnancy and childbirth among postpartum women living in the municipality of Rio Grande, Southern Brazil, using data from surveys carried out every three years between 2007 and 2019.

METHODS

Within 48 hours after delivery, a single, standardized questionnaire was applied to all mothers who had children in local hospitals and met the inclusion criteria. Demographic and reproductive characteristics, lifestyle habits, socioeconomic level of the family, and care received during pregnancy and childbirth were investigated. In the analysis, the chi-square test for linear trend was used to assess the distribution of indicators per survey.

RESULTS

A total of 12,645 parturients were interviewed (98% of the women eligible to participate in the surveys). In the period evaluated, the proportion of births fell 35% among adolescents and increased 25% among women aged 35 years and over. Mothers gained, on average, two years of schooling, and their families experienced an important economic improvement, followed by loss of income in the last survey. Maternal smoking, before and during pregnancy, fell by half. The rate of mothers who started prenatal care in the first trimester and the number of consultations and laboratory tests increased. Almost 60% of prenatal consultations and 80% of births took place in the Brazilian Unified Health System. In 2019, vaginal delivery was once again the most common. The rates of low birth weight (9%) and prematurity (17%) virtually remained unchanged.

CONCLUSIONS

We found an important change in the reproductive profile and increased coverage of various prenatal care and delivery services. Children continue to be born well, but low birth weight and prematurity remain endemic.

Vaccination services and incomplete vaccine coverage for children: a comparative spatial analysis of the BRISA cohorts, São Luís (Maranhão State) and Ribeirão Preto (São Paulo State), Brazil

We analyzed the spatial relation between incomplete vaccine coverage for children and the distance from vaccination services. This was a cross-sectional study of children from 13 to 35 months of age from the cities of São Luís (Maranhão State) and Ribeirão Preto (São Paulo State), Brazil, and from basic health units (UBS, in Portuguese). The sample consisted of 2,744 children from São Luís and 3,325 from Ribeirão Preto. Data about incomplete vaccine coverage for children were obtained from the BRISA birth cohorts. Data about the quality of UBS vaccination services were obtained from the first cycle of the Brazilian National Program for Improvement of Access and Quality of Basic Care (PMAQ-AB, in Portuguese). For the spatial analysis, we determined the distance between the residence of the children (with and without a complete vaccine calendar) and the vaccination services of the UBS (classified according to number of structural items). Incomplete vaccine coverage was more pronounced in São Luís, with greater percentages for human rotavirus and triple viral vaccines, with the latter being the least available. In Ribeirão Preto, incomplete BCG vaccine coverage was more pronounced, with the tetravalent vaccine being the least available. Children from the two cities showed similarities: most of them had adult mothers with 9 to 11 years of schooling and did not reside with siblings in the household. They also showed differences: in São Luís, most mothers belonged to the economic class C, while in Ribeirão Preto they belong to the A and B classes. In the two cities with different socioeconomic conditions, complete vaccine coverage seemed not to depend on the location or quality of the vaccination service. Although São Luís showed a better structure of the services, incomplete vaccine coverage was higher compared to Ribeirão Preto.

Prevalence and factors associated with unplanned pregnancy in a Brazilian capital in the Northeast

Abstract Objectives: to analyze the prevalence and factors associated with unplanned pregnancy in a Brazilian capital in the Northeast. Methods: a cross-sectional study nested to a hospital birth cohort with a probable sample of 5,110 puerperal women. Associated factors were analyzed using a hierarchical theoretical model in three levels: distal (women’s socioeconomic and demographic characteristics), intermediate (reproductive characteristics, maternal habits and BMI), and proximal level (partner's characteristics). Multivariate Poisson regression analysis was performed. Results: the prevalence of unplanned pregnancy was 68.1% (CI95%=66.8-69.4). Multivariate analysis showed association with black skin color/race (PR=1.03; CI95%=1.01- 1.07), mother's age group up to 19 years old (PR=1.09; CI95%=1.06-1.12) and 20 to 24 years old (PR=1.04; CI95%=1.01-1.07), not living with partner (PR=1.09; CI95%=1.07- 1.11), highest number of people in the household: 5 people (PR= 1.10; CI95%=1.08-1.13) and 3 to 4 (PR=1.08; CI95%=1.05-1.10), number of ≥4 children (PR=1.09; CI95%=1.06- 1.13) and 2 or 3 children (PR=1.03; CI95%=1.02-1.05), alcohol consumption (PR=1.03; CI95%=1.01-1.05), malnourished pre-pregnancy BMI (PR=1.03; CI95%=1.01-1.06) and partner’s low schooling (5 to 8 years) (PR=1.03; CI95%=1.01-1.07). Prior abortion was inversely associated with planned pregnancy (PR=0.95; CI95%=0.93-0.97). Conclusions: the prevalence of unplanned pregnancy was high and was associated with socioeconomic and demographic characteristics that reflect on the combination of the complex inequalities that impact women and their partners

Sociodemographic profile of primiparous mothers from nine birth cohorts in three Brazilian cities

Fertility reduction is a phenomenon observed in demographic transition. The demographic changes noted in female fertility represent a need for adjustment on health services regarding female health and family planning support. Thus, this study aimed to perform a descriptive analysis by tracing the sociodemographic profile of primiparous mothers belonging to nine Brazilian birth cohorts, in three cities from different states. Standardized questionnaires were applied to assess reproductive characteristics and covariables. Primiparous mothers were defined as women whose child included in birth cohorts was their firstborn child. Sample description was performed using analysis of variance (continuous variables) and chi-square (categorical variables). In total, 44,615 women were included in the analyses and 41.8% (95%CI: 41.3; 42.2) were categorized as primiparous. The primiparity rates were the lowest in Ribeirão Preto (São Paulo State) 1978 (32%; 95%CI: 30.9; 33.1) and the highest in most recent cohorts, reaching up to 50% of the participants (São Luís - Maranhão State 2010: 47.2%; 95%CI: 45.8; 48.6; Ribeirão Preto 2010: 50.2%; 95%CI: 49.1; 51.4); Pelotas (Rio Grande do Sul State) 2015: 49.4% (95%CI: 47.9; 50.9). Primiparous mothers' age and schooling increased over the years in all cohorts. Maternal age at the first childbirth behaved similarly in the three studied cities. There was an increase in the proportion of first-time mothers that were older, higher educated and belonged to richer income groups. Also, the proportion of teenage mothers (aged 15 years or younger) increased until the early 2000's and started decreasing around the years 2010, especially among women in the poorer income groups.

RPS Brazilian Birth Cohorts Consortium (Ribeirão Preto, Pelotas and São Luís): history, objectives and methods

This paper describes the history, objectives and methods used by the nine Brazilian cohorts of the RPS Brazilian Birth Cohorts Consortium (Ribeirão Preto, Pelotas and São Luís) Common thematic axes are identified and the objectives, baseline periods, follow-up stages and representativity of the population studied are presented. The Consortium includes three birth cohorts from Ribeirão Preto, São Paulo State (1978/1979, 1994 and 2010), four from Pelotas, Rio Grande do Sul State (1982, 1993, 2004 and 2015), and two from São Luís, Maranhão State (1997 and 2010). The cohorts cover three regions of Brazil, from three distinct states, with marked socioeconomic, cultural and infrastructure differences. The cohorts were started at birth, except for the most recent one in each municipality, where mothers were recruited during pregnancy. The instruments for data collection have been refined in order to approach different exposures during the early phases of life and their long-term influence on the health-disease process. The investigators of the nine cohorts carried out perinatal studies and later studied human capital, mental health, nutrition and precursor signs of noncommunicable diseases. A total of 17,636 liveborns were recruited in Ribeirão Preto, 19,669 in Pelotas, and 7,659 in São Luís. In the studies starting during pregnancy, 1,400 pregnant women were interviewed in Ribeirão Preto, 3,199 in Pelotas, and 1,447 in São Luís. Different strategies were employed to reduce losses to follow-up. This research network allows the analysis of the incidence of diseases and the establishment of possible causal relations that might explain the health outcomes of these populations in order to contribute to the development of governmental actions and health policies more consistent with reality.

Is birth weight associated with pregestational maternal BMI? BRISA Cohort, Ribeirão Preto, Brazil

Given the increase of women with excess weight or obesity and its possible effects on birth weight, the present study aimed to investigate the association between pregestational maternal body mass index (BMI) and birth weight in a birth cohort from Ribeirão Preto, SP, Brazil. This was a prospective study conducted on 1362 mother-child pairs involving singleton births. The women were evaluated using standardized questionnaires during the second trimester of pregnancy and at the time of childbirth. Information about the newborns was obtained from their medical records. The dependent variable was birth weight, categorized as low, adequate, or high. The independent variable was pregestational maternal BMI, categorized as malnutrition, adequate weight, overweight, and obesity. A multinomial regression model was used to estimate the crude and adjusted relative risk (RR) of low and high birth weight. A high frequency of pregestational excess weight (39.6%) was detected and found to be independently associated with high birth weight (RR=2.13, 95%CI: 1.19-3.80 for overweight and RR=3.34, 95%CI: 1.80-6.19 for obese pregnant women). There was no association between pregestational malnutrition and low birth weight (RR=1.70; 95%CI: 0.81-3.55). The present data showed a high rate of women with excess pregestational weight, supporting the hypothesis that pregestational BMI may contribute to high birth weight babies and indicating the need for actions aiming to prevent excessive weight in women at reproductive age.

Psychological distress and mother-child relationship: influence of life context on a population sample (BRISA) through the use of directed acyclic graphs (DAG)

This study aimed to investigate the association between maternal psychological distress and impairment in mother-child relationship in a sample from a Northeast capital city in Brazil with a low Human Development Index, using directed acyclic graphs (DAG). A total of 3,215 women were evaluated for the presence of psychological distress through the Self Reporting Questionnaire instrument and for the mother-child relationship by the first factor of Postpartum Bonding Questionnaire, considered the most appropriate in the literature. Demographic and socioeconomic variables were used to construct a theoretical model and, after this, multivariate logistic regression was performed using variables suggested by Directed Acyclic Graphs (DAG). Psychological distress was present in 22.7% of the women and 12.6% of them presented impaired mother-child relationships. After adjustment, the variable 'maternal mental distress' remained associated with impaired mother-child relationship (RR=3.03), and among the explanatory variables only 'primary school level' (RR=1.48) was associated as a risk factor to this outcome. The results indicated that, in this population, women with psychological distress and lower schooling are more likely to present impaired mother-child relationships.

Determinants of the introduction of early complementary feeding before and after the third month of life: a multinomial analysis

The introduction of early complementary feeding (ECF) is determined by different factors depending on when it occurs. The objective of this study was to analyze factors associated with the introduction of ECF in two different moments of the infant's life: from zero to three and from four to five months of age. A cohort with 3,306 dyads studied in the BRISA survey in São Luis/MA in 2010 was used. Questionnaires were applied at birth and at follow-up when the infants were 15 to 36 months of age of women with more than 20 weeks of gestational age, residing in this municipality. A multivariate model of multinomial logistic regression was used to verify associations between independent variables and ECF at 0 to 3 months and at 4 to 5 months of age. A hierarchical analysis model was used to select variables for confounding adjustment. Variables with a P-value <0.05 were considered significant. For ECF introduced between 0-3 months, the variables "use of pacifier", "maternal paid activity", "smoking", and "postpartum pregnancy" were identified as risk factors. The variables "use of pacifier" and "maternal paid activity" remained associated as a risk for ECF introduced from 4-5 months. The variable 'mother without partner' (RR=1.26 and P=0.04) represented a risk factor for ECF only for the 4-5 months period. Although each period presented specific risk factors, the use of pacifier and maternal professional activity were associated in the two periods studied, indicating their importance for the introduction of ECF.

Bolsa Família program and incomplete childhood vaccination in two Brazilian cohorts

OBJECTIVE:

To estimate the effect of being a beneficiary of the Bolsa Família Program (BFP) in the vaccination of children aged 13 to 35 months.

METHODS:

Our study was based on all birth records of residents of Ribeirão Preto (SP) and probabilistic sampling with 1/3 of the births of residents of São Luís (MA), selecting low-income children, born in 2010, belonging to the cohorts Brazilian Ribeirão Preto and São Luís Birth Cohort Studies and eligible for the Bolsa Família program. The information of Cadastro Único (CadÚnico – Single Registry) was used to categorize the receipt of benefit from the BFP (yes or no). The final sample consisted of 532 children in Ribeirão Preto and 1,229 in São Luís. The outcome variable was a childhood vaccine regimen, constructed with BCG, tetravalent, triple viral, hepatitis B, poliomyelitis, rotavirus and yellow fever vaccines. The adjustment variables were: economic class, mother's schooling and mother's skin color. Children with monthly per capita family income of up to R$ 280.00 and/or economic class D/E were considered eligible for the benefit of the BFP. A theoretical model was constructed using a directed acyclic graph to estimate the effect of being a beneficiary of the BFP in the vaccination of low-income children. In the statistical analyses, weighing was used by the inverse of the probability of exposure and pairing by propensity score.

RESULTS:

Considering a monthly per capita family income of up to R$ 280.00, being a beneficiary of the BFP had no effect on the childhood vaccination schedule, according to weighing by the inverse of the probability of exposure (SL-coefficient: −0.01; 95%CI −0.07 to 0.04; p = 0.725 and RP-coefficient: 0.04; 95%CI −0.02 to 0.10; p = 0.244) and pairing by propensity score (SL-coefficient: −0.01; 95%CI −0.07 to 0.05; p = 0.744 and RP-coefficient: 0.04; 95%CI −0.02 to 0.10; p = 0.231).

CONCLUSIONS:

The receipt of the benefit of the BFP did not influence childhood vaccination, which is one of the conditionalities of the program. This may indicate that this conditionality is not being adequately monitored.

Brazilian cohorts with potential for life-course studies: a scoping review

OBJECTIVE To identify the Brazilian cohorts that started either in the prenatal period or at birth, to describe their characteristics and the explored variables, and to map the cohorts with potential for studies on early determinants on health and the risk of falling ill on later stages of the life cycle. METHODS A scoping review was carried out. The articles were searched in the electronic databases PubMed and Virtual Health Library (VHL). The descriptors used were [((("Child" OR "Child, Preschool" OR "Infant" OR "Infant, Newborn") AND (Cohort Studies" OR "Longitudinal Studies")) AND "Brazil")]. The inclusion criteria were Brazilian cohorts that started the baseline in the prenatal period or at birth and with at least two follow-ups with the participants. In order to meet the concept of LCE, we excluded those cohorts whose follow-ups were restricted to the first year of life, as well as those that did not address biological, behavioral and psychosocial aspects, and cohorts with data collection of a single stage of the life cycle. RESULTS The search step identified 5,010 articles. Eighteen cohorts were selected for descriptive synthesis. The median number of baseline participants was 2,000 individuals and the median age at the last follow-up was 9 years. Sample loss at the last follow-up ranged from 9.2 to 87.5%. Most cohorts monitored two phases of the life cycle (the perinatal period and childhood). The Southern region had the highest number of cohorts. The main variables collected were sociodemographic and environmental aspects of the family, morbidity aspects, nutritional practices and lifestyle. CONCLUSIONS We recommend the continuity of these cohorts, the approach to different social contexts and the performance of follow-ups with participants in different phases of the life cycle for the strengthening and expansion of life course epidemiology analyses in Brazil.

Mean birth weight among term newborns: direction, magnitude and associated factors

A trend towards increasing birth weight has been shown, but factors that explain these trends have not been elucidated. The objectives of this study were to evaluate changes in mean birth weight of term newborns and to identify factors associated with them. All cohorts are population-based studies in which random samples of births (Ribeirão Preto, São Paulo State in 1978/1979, 1994 and 2010; Pelotas, Rio Grande do Sul State in 1982, 1993 and 2004; and São Luís, Maranhão State in 1997/1998 and 2010, Brazil). A total of 32,147 full-term, singleton live births were included. Mean birth weight reduced in the first study period (-89.1g in Ribeirão Preto from 1978/1979 to 1994, and -27.7g in Pelotas from 1982 to 1993) and increased +30.2g in Ribeirão Preto from 1994 to 2010 and +24.7g in São Luís from 1997 to 2010. In the first period, in Ribeirão Preto, mean birth weight reduction was steeper among mothers with high school education and among those born 39-41 weeks. In the second period, the increase in mean birth weight was steeper among mothers with low schooling in Ribeirão Preto and São Luís, females and those born 37-38 weeks in Ribeirão Preto and cesarean section in São Luís. Birth weight decreased in the first study period then increased thereafter. The variables that seem to have been able to explain these changes varied over time.

Changes in Infant and Neonatal Mortality and Associated Factors in Eight Cohorts from Three Brazilian Cities

Stillbirth (SBR), perinatal (PMR), neonatal (NMR) and infant mortality rates (IMR) are declining in Brazil and the factors associated with these falls are still being investigated. The objective of the present study was to assess changes in SBR, PMR, NMR and IMR over time and to determine the factors associated with changes in NMR and IMR in eight Brazilian cohorts. All cohorts are population-based (Ribeirão Preto in 1978/79, 1994 and 2010; Pelotas in 1982, 1993 and 2004; and São Luís in 1997/98 and 2010). Were included data on 41440 children. All indicators were decreased, except in the city of Pelotas, from 1993 to 2004, and except SBR in São Luís. Sociodemographic variables seem to be able to explain reductions of NMR and IMR in Ribeirão Preto, from 1978/79 to 1994, and in São Luís. In Ribeirão Preto, from 1994 to 2010 declines in NMR and IMR seem to be explained by reductions in intrauterine growth restriction (IUGR). Newborn’s gestational age had diminished in all cohorts, preventing even greater reductions of NMR and IMR. Improved sociodemographic variables and reduction of IUGR, seem to be able to explain part of the decrease observed. NMR and IMR could have been reduced even more, were it not for the worsening in gestational age distribution.

Mental disorders in adolescents, youth, and adults in the RPS Birth Cohort Consortium (Ribeirão Preto, Pelotas and São Luís), Brazil

Although depression and anxiety are known to result in disabilities and workplace and health system losses, population-based studies on this problem are rare in Brazil. The current study assessed the prevalence of mental disorders in adolescents, youth, and adults and the relationship to sociodemographic characteristics in five birth cohorts (RPS) in Ribeirão Preto (São Paulo State), Pelotas (Rio Grande do Sul State), and São Luís (Maranhão State), Brazil. Major depressive episode, suicide risk, social phobia, and generalized anxiety disorder were assessed with the Mini International Neuropsychiatric Interview. Bootstrap confidence intervals were estimated and prevalence rates were stratified by sex and socioeconomic status in the R program. The study included 12,350 participants from the cohorts. Current major depressive episode was more prevalent in adolescents in São Luís (15.8%; 95%CI: 14.8-16.8) and adults in Ribeirão Preto (12.9%; 95%CI: 12.0-13.9). The highest prevalence rates for suicide risk were in adults in Ribeirão Preto (13.7%; 95%CI: 12.7-14.7), and the highest rates for social phobia and generalized anxiety were in youth in Pelotas, with 7% (95%CI: 6.3-7.7) and 16.5% (95%CI: 15.4-17.5), respectively. The lowest prevalence rates of suicide risk were in youth in Pelotas (8.8%; 95%CI: 8.0-9.6), social phobia in youth in Ribeirão Preto (1.8%; 95%CI: 1.5-2.2), and generalized anxiety in adolescents in São Luís (3.5%; 95%CI: 3.0-4.0). Mental disorders in general were more prevalent in women and in individuals with lower socioeconomic status, independently of the city and age, emphasizing the need for more investment in mental health in Brazil, including gender and socioeconomic determinants.

Factors associated with the development of dental defects acquired in the extrauterine environment

This study aimed to analyze the association of sociodemographic, child health, healthcare service, and access indicators with developmental defects of enamel (DDE) acquired outside the uterus, based on gestational factors. A cohort of births was carried out, and 982 children aged 12 to 30 months were examined. A total of 1,500 women were followed up as of the 5th month of gestation, and the child's gestational age was evaluated at follow-up. The clinical examination was performed as recommended by the World Health Organization, and defects were classified using the modified DDE index. Six models were considered: presence of DDE (Model 1) or opacities (Model 4), number of teeth with DDE (Model 2) or opacities (Model 5), and incidence rate of DDE (Model 3) or opacities (Model 6). Associations were estimated by relative risk (RR) in Poisson regression models. In the adjusted analysis, the mother's lowest education level was associated with the highest occurrence of DDE in Models 1 (RR = 26.43; p = 0.002), 2 (RR = 9.70; p = 0.009), and 3 (RR = 5.63; p = 0.047). Breastfeeding for over 12 months (RR = 0.45; p = 0.030) and recent use of anti-infection drugs (RR = 0.20; p = 0.039) had a protective effect on DDE (Model 1). The factors associated with the highest incidence of opacities were not having health insurance (RR = 2.00; p = 0.043) (Model 5), and belonging to a family of poor social class (RR = 4.67; p = 0.007) (Model 6). Children in a situation of socioeconomic vulnerability have a higher risk of presenting extrauterine DDE. Breastfeeding was a protection factor for DDE development.

[Eating patterns among children aged 13 to 35 months and association with maternal characteristics]

This study sought to identify eating patterns among children and to verify their association with maternal characteristics. We studied 1,185 children aged 13 to 35 months. Food consumption was investigated using the 24h dietary recall and the eating patterns were identified using principal components factor analysis, followed by orthogonal varimax rotation. We carried out a hierarchical modeling using poisson regression with robust variance estimates in order to estimate prevalence ratios. We identified four eating patterns: common Brazilian, dairy/porridge, healthy and unhealthy. The variance explained by these factors was of 34.3% and the common Brazilian pattern was the one that most contributed to proportional variance. We highlight the dairy/porridge pattern, in which breast milk had negative factorial loading, suggesting its substitution by cow and modified milk. The data reveal that the characterization of children's eating patterns diverges according to maternal characteristics, such as age, educational level and number of children. Three of the four patterns we found are represented by foods rich in starch, saturated fat and simple sugar and poor in vitamins, minerals and fibers. Multiparity, lower educational levels and maternal age under 20 years were associated with a lower consumption of foods considered to be healthy and important in child development.

Foco e cobertura do programa Bolsa Família em crianças das coortes de nascimento BRISA, Ribeirão Preto (São Paulo) e São Luís (Maranhão), Brasil

Estudo transversal aninhado a uma coorte, que teve como objetivo descrever foco e cobertura do programa Bolsa Família em crianças de 13-35 meses de idade. Fez-se uso de dados das coortes de nascimento BRISA, em Ribeirão Preto, São Paulo, e São Luís, Maranhão, Brasil. O início das coortes ocorreu em 2010, com a inclusão de todos os nascimentos em Ribeirão Preto (7.794) e 5.236 em São Luís, abrangendo amostra aleatória de um terço. No seguimento, realizado de 2011 a 2013, retornaram 3.805 crianças em Ribeirão Preto e 3.308 em São Luís. Foram utilizados dados do momento do seguimento, e estes foram integrados às informações do Cadastro Único (CadÚnico). Consideraram-se dois critérios de elegibilidade para o benefício do Bolsa Família: renda familiar per capita mensal de até R$ 140,00 e classe econômica D/E. Estimaram-se percentuais de foco e cobertura do Bolsa Família. Realizou-se ponderação para perdas de seguimento. O foco do Bolsa Família, segundo renda familiar per capita mensal, foi de 33,8% em São Luís e 15,9% em Ribeirão Preto, e de acordo com a classe econômica foi de 33,7% em São Luís e 15,3% em Ribeirão Preto. A cobertura do Bolsa Família, de acordo com o critério de renda familiar per capita mensal, foi de 82,1% em São Luís e 71,6% em Ribeirão Preto; e segundo classe econômica foi de 68,9% em São Luís e 46,8% em Ribeirão Preto. Foram baixos os percentuais de foco e melhores os de cobertura do Bolsa Família, com estimativas destes indicadores maiores para São Luís em relação a Ribeirão Preto.

[Factors associated with the involuntary pilgrimage for childbirth care in São Luís (Maranhão State) and Ribeirão Preto (São Paulo State), Brazil: a contribution from the BRISA cohort]

The objectives of this study were to estimate the involuntary pilgrimage by women in labor in search of childbirth care and to identify factors associated with this endeavor in two Brazilian cities. This was a cross-sectional study nested in the BRISA birth cohort, whose sample consisted of 10,475 women admitted to the selected maternity hospitals for delivery in São Luís (Maranhão State) and Ribeirão Preto (São Paulo State). Interviews were held with questionnaires that contained sociodemographic and obstetric variables. Hierarchical modeling was used, and relative risk was calculated with Poisson regression. Involuntary pilgrimage during labor was more frequent in São Luís (35.8%) than in Ribeirão Preto (5.8%). In São Luís, factors associated with pilgrimage were: first pregnancy (RR = 1.19; 95%CI: 1.08-1.31) and schooling less than 12 complete years. However, age 35 years or older (RR = 0.65; 95%CI: 0.54-0.84) was associated with less pilgrimage. In Ribeirão Preto, such trekking for obstetric care was more frequent in women with high-risk pregnancies (RR = 2.45; 95%CI: 1.81-3.32) and those with gestational age less than 37 weeks (RR = 1.93; 95%CI: 1.50-2.50). Meanwhile, delivery with gestational age equal to or greater than 42 weeks was associated with less pilgrimage (RR = 0.57; 95%CI: 0.33-0.98). In both cities, poor women had to trek more in search of childbirth care and had no guarantee of care, even for those who had received prenatal care. The study revealed the lack of guarantee of universal and equitable access and highlighted the unequal access to childbirth care between Brazil's major geographic regions.

Prepregnancy body mass index, gestational weight gain, and birth weight in the BRISA cohort

OBJECTIVE To analyze the effects of maternal pre-pregnancy body mass index and weight gain during pregnancy on the baby's birth weight. METHODS We conducted a cross-sectional study with 5,024 mothers and their newborns using a Brazilian birth cohort study. In the proposed model, estimated by structural equation modeling, we tested socioeconomic status, age, marital status, pre-pregnancy body mass index, smoking habit and alcohol consumption during pregnancy, hypertension and gestational diabetes, gestational weight gain, and type of delivery as determinants of the baby's birth weight. RESULTS For a gain of 4 kg/m2 (1 Standard Deviation [SD]) in pre-pregnancy body mass index, there was a 0.126 SD increase in birth weight, corresponding to 68 grams (p < 0.001). A 6 kg increase (1 SD) in gestational weight gain represented a 0.280 SD increase in newborn weight, correponding to 151.2 grams (p < 0.001). The positive effect of pre-pregnancy body mass index on birth weight was direct (standardized coefficient [SC] = 0.202; p < 0.001), but the negative indirect effect was small (SC = -0.076, p < 0.001) and partially mediated by the lower weight gain during pregnancy (SC = -0.070, p < 0.001). The positive effect of weight gain during pregnany on birth weight was predominantly direct (SC = 0.269, p < 0.001), with a small indirect effect of cesarean delivery (SC = 0.011; p < 0.001). Women with a higher pre-pregnancy body mass index gained less weight during pregnancy (p < 0.001). CONCLUSIONS The effect of gestational weight gain on the increase in birth weight was greater than that of pre-pregnancy body mass index.

Incomplete childhood immunization with new and old vaccines and associated factors: BRISA birth cohort, São Luís, Maranhão State, Northeast Brazil

This study estimated the percentages of incomplete immunization with new vaccines and old vaccines and associated factors in children 13 to 35 months of age belonging to a birth cohort in São Luís, the capital of Maranhão State, Brazil. The sample was probabilistic, with 3,076 children born in 2010. Information on vaccination was obtained from the Child's Health Card. The new vaccines, namely those introduced in 2010, were meningococcal C and 10-valent pneumococcal, and the old vaccines, or those already on the childhood immunization schedule, were BCG, hepatitis B, human rotavirus, polio, tetravalent (diphtheria, tetanus, pertussis, Haemophilus influenzae b), yellow fever, and triple viral (measles, mumps, rubella). The study used hierarchical modeling and Poisson regression with robust variance. Prevalence ratios (PR) and 95% confidence intervals (95%CI) were calculated. Incomplete immunization was higher with new vaccines (51.1%) than with old vaccines (33.2%). Children 25 to 35 months of age (PR = 1.27; 95%CI: 1.14-1.41) and those in economic classes D/E (PR = 1.20; 95%CI: 1.06-1.35) were only significantly associated with new vaccines; low maternal schooling (PR = 1.58; 95%CI: 1.21-2.06), unavailability of outpatient and/or hospital care for the child (PR = 1.20; 95%CI: 1.04-1.38), and unavailability of the vaccine in health services (PR: 1.28; 95%CI: 1.12-1.46) were only associated with old vaccines. Immunization strategies should consider the vulnerability of older preschool-age children and those belonging to classes D and E, especially when new vaccines are introduced, as well as children of mothers with low schooling. Strategies should also address problems with the availability of health services and vaccines.

Prevalence and Risk Factors for Microcephaly at Birth in Brazil in 2010

OBJECTIVES

To estimate the baseline prevalence and risk factors for microcephaly at birth before the Zika virus epidemic in 2 Brazilian cities.

METHODS

We used population-based data from the Brazilian Ribeirão Preto (RP) and São Luís (SL) birth cohort studies of 2010 that included hospital deliveries by resident mothers. The final sample was 7376 live births in RP and 4220 in SL. Gestational age was based on the date of the mother's last normal menstrual period or obstetric ultrasonography, if available. Microcephaly at birth was classified according to the criteria of the International Fetal and Newborn Growth Consortium for the 21st Century and the Brazilian Ministry of Health. Risk factors for microcephaly, proportionate and disproportionate microcephaly, and severe microcephaly were estimated in a hierarchized logistic regression model.

RESULTS

According to the International Fetal and Newborn Growth Consortium for the 21st Century definition, the prevalence of microcephaly (>2 SDs below the mean for gestational age and sex) was higher in SL (3.5%) than in RP (2.5%). The prevalence of severe microcephaly (>3 SDs below the mean) was higher in SL (0.7%) than in RP (0.5%). Low maternal schooling, living in consensual union or without a companion, maternal smoking during pregnancy, primiparity, vaginal delivery, and intrauterine growth restriction were consistently associated with microcephaly. The number of cases of microcephaly is grossly underestimated, with an underreporting rate of ∼90%.

CONCLUSIONS

The prevalence of severe microcephaly was much higher than expected in both cities. Our findings suggest that microcephaly was endemic in both municipalities before the circulation of the Zika virus.

Maternal socioeconomic factors and adverse perinatal outcomes in two birth cohorts, 1997/98 and 2010, in São Luís, Brazil

ABSTRACT: Several studies have identified social inequalities in low birth weight (LBW), preterm birth (PTB), and intrauterine growth restriction (IUGR), which, in recent years, have diminished or disappeared in certain locations. Objectives: Estimate the LBW, PTB, and IUGR rates in São Luís, Maranhão, Brazil, in 2010, and check for associations between socioeconomic factors and these indicators. Methods: This study is based on a birth cohort performed in São Luís. It included 5,051 singleton hospital births in 2010. The chi-square test was used for proportion comparisons, while simple and multiple Poisson regression models with robust error variance were used to estimate relative risks. Results: LBW, PTB and IUGR rates were 7.5, 12.2, and 10.3% respectively. LBW was higher in low-income families, while PTB and IUGR were not associated with socioeconomic factors. Conclusion: The absence or weak association of these indicators with social inequality point to improvements in health care and/or in social conditions in São Luís.

Processed and ultra-processed food consumption among children aged 13 to 35 months and associated factors

Abstract: The aim of this study was to evaluate the consumption of processed and ultra-processed foods among children aged 13-35 months and its associated factors. We studied 1,185 children within the BRISA cohort in São Luís, Maranhão State, Brazil. The food consumption was investigated using a 24-hour recall, and the percentages of daily caloric intake and nutrients were estimated by food groups according to “NOVA” classification. We chose to categorize children belonging to the upper tertile of the distribution as having a high consumption of processed and ultra-processed food products. The Poisson regression model with robust variance estimation using a hierarchical modeling approach was used to calculate the prevalence ratios (PRs) of variables associated with high consumption of processed and ultra-processed food products. The mean energy intake was 1,226Kcal/day. After adjustments, there was a higher proportion of high consumption of processed and ultra-processed food products among children whose mothers had < 12 years of education and among children who were older than 16 months. Mothers with low schooling and children older than 16 months should be the targets of interventions aimed at reducing consumption of these food products and preventing adverse health outcomes in later life.

[Effects of gestational weight gain and breastfeeding on postpartum weight retention among women in the BRISA cohort]

This study analyzed the effects of gestational weight gain and breastfeeding on postpartum weight retention. The study followed 2,607 women from the BRISA cohort. The variables were age, socioeconomic status, parity, pre-gestational body mass index, gestational weight gain, duration of maternal breastfeeding, length of postpartum follow-up, and postpartum weight gain. Structural equation modeling was used to evaluate the total, direct, and indirect effects of the explanatory variables on postpartum weight retention. An increase of one standard deviation in gestational weight gain corresponded to a significant increase of 0.49 standard deviations in postpartum weight retention (p < 0.001). An increase of one standard deviation in duration of breastfeeding corresponded to mean decrease of 0.10 standard deviations in postpartum weight retention (p < 0.001). Independently of pre-gestational BMI, gestational weight gain is a risk factor and duration of breastfeeding is a protective factor against postpartum weight retention.