Trends and inequalities in maternal and child health in a Brazilian city: methodology and sociodemographic description of four population-based birth cohort studies, 1982-2015

Prepregnancy maternal BMI and trajectories of BMI-for-age in children up to four years of age: findings from the 2015 Pelotas (Brazil) birth cohort

BACKGROUND

The aims of the study were to: (a) describe BMI-for-age trajectories in children up to four years of age; (b) evaluate the association between prepregnancy maternal BMI and the BMI-for-age trajectories.

METHODS

Data from 3218 (75.3% of the original cohort) children from the Pelotas 2015 Birth Cohort were analyzed. Prepregnancy BMI (kg/m2) was measured on the perinatal interview. Z-scores of BMI-for-age were calculated for children at three months, 1, 2 and 4 years. Trajectories were identified using a semi-parametric group-based modeling approach. Multinomial logistic regression was used to test the association between prepregnancy BMI (weight excess: BMI ≥ 25 kg/m2) and BMI-for-age trajectories.

RESULTS

Four trajectories of the BMI-for-age, in z-score, were identified and represent children in the "increasing", "adequate", "stabilized" and "risk for weight excess" group. A total of 196 children (7.1%) belonged to the group that was at risk of weight excess. Adjusted analyses showed that children whose mothers presented prepregnancy weight excess had 2.36 (95%CI 1.71; 3.24) times more risk of belonging to group "risk for weight excess" when compared to those children whose mothers presented underweight/normal weight before pregnancy.

CONCLUSION

The risk of weight excess in children up to 4 years of age were greater in mothers who presented prepregnancy weight excess.

Lack of association between month of birth and risk of developing type 1 diabetes in Brazil: a 40-year analysis

OBJECTIVES

Seasonal environment at birth may influence diabetes incidence in later life. We sought evidence for this effect and analyzed the association between the month of birth and the risk of developing type 1 diabetes mellitus (T1DM).

METHODS

This was a cohort study carried out with 814 patients diagnosed with T1DM in the region of Bauru - São Paulo State, Brazil, receiving medical care in a private Endocrinology clinic or in the public Brazilian National Health Care System, from 1981 to 2021. All live births that occurred in São Paulo State between 1974 and 2020 were classified by month of birth and were considered as the control group.

RESULTS

We found no statistically significant difference (χ2=16.31, critical 19.68) between the month of birth and risk of developing T1DM, when comparing our patients with the background population of the region. There was no association between the month of birth, sex, age at diagnosis, duration of symptoms before diagnosis, self-reported color, and socioeconomic status.

CONCLUSIONS

We found no association between month of birth and the risk of developing T1DM in this highly admixed South American population. Our data suggest that our population heterogeneity and geographic location may be important factors in the development of T1DM. Future prospective studies, evaluating environmental factors that may confer risk or protection to the disease, are warranted.

Cross-sectional and prospective associations between screen time and childhood neurodevelopment in two Brazilian cohorts born 11 years apart

BACKGROUND

The aim of this study was to investigate the associations between screen time from ages 2 to 4 years and child neurodevelopment at age 4.

METHODS

The participants were from the 2004 (N = 3787) and 2015 (N = 3604) Pelotas (Brazil) birth cohort studies. Childhood neurodevelopment was assessed at age 4 using the Battelle Development Inventory. The time children spent on screen devices was reported by their guardians at ages 2 and 4 years. Linear regression models were used to investigate the association of: (i) time spent on television at ages 2 and 4 years; (ii) time spent on other screens at age 4; and (iii) total screen time at age 4 (television + other screens) with childhood neurodevelopment at age 4.

RESULTS

Average daily screen time among children born in 2004 and those born in 2005 aged 4 years were 3.4 (SD: 2.4) and 4.4 h (SD: 2.9), respectively. Overall, few associations of very small magnitude between screen time and child neurodevelopment were observed. Television time at 2 years of age was statistically associated with lower neurodevelopment at 4 years of age in the 2015 cohort (β = -0.30, 95%CI = -0.55; -0.05). Conversely, television time (β = 0.17, 95%CI = 0.07, 0.26) and total screen time (β = 0.22, 95%CI = 0.13, 0.31) at age 4 were associated with higher neurodevelopment at age 4 in the 2004 cohort.

CONCLUSIONS

The findings of this study suggest that the amount of time spent on screen devices might not be associated with neurodevelopment of children under 5 years of age. The small magnitude and inconsistencies in the direction of associations did not find evidence to support the current guidelines for screen time at this age. Therefore, more studies, especially those with longitudinal data, are important to comprehend the true effect of screen time on neurodevelopment and other health outcomes.

Factors associated with respiratory morbidity in the first year of life

OBJECTIVES

To investigate the association between socioeconomic and nutritional factors with respiratory morbidity in the first year of life in different regions of Brazil.

METHODOLOGY

A nested case-control study within a randomized field trial was conducted in three capital cities (Porto Alegre, Manaus, and Salvador), representing different macro-regions of the country. Cases were defined as children with a reported previous diagnosis of asthma, bronchiolitis, or pneumonia. Corresponding controls were matched by age and sex in a 2:1 ratio, selected consecutively from the original cohort, resulting in a sample of 222 children. Bivariate analyses were performed to assess the association between sociodemographic and nutritional variables with respiratory morbidity outcomes, calculating odds ratios (OR) and their respective confidence intervals (95% CI). Values of p < 0.05 were considered significant. Potential confounding factors were adjusted through multivariate analysis (logistic regression).

RESULTS

Maternal smoking and breastfeeding for less than six months showed a significant association and increased risk of respiratory disease (OR=2.12 and 2.05, respectively). Children born in the Southern region of Brazil also demonstrated a higher association and risk of respiratory morbidity. The consumption of ultra-processed foods did not show a significant association or increased risk of respiratory disease.

CONCLUSIONS

Maternal smoking, breastfeeding for less than six months, and being born in the Southern region of Brazil are risk factors for the development of respiratory morbidity in the first year of life. The consumption of ultra-processed foods does not appear to pose a risk, but it was prevalent in more than 80% of the population, limiting its discriminatory power of analysis.

Physical Activity and Chronic Stress in Early Life: Findings From the 2015 Pelotas (Brazil) Birth Cohort

BACKGROUND

The association of physical activity through early childhood on children's chronic stress still is unclear. Therefore, the aim of the present study is to test the association of physical activity through early childhood (1-4 y) with chronic stress, measured by hair cortisol at age 4.

METHODS

Longitudinal study including children from the 2015 Pelotas (Brazil) Birth Cohort. Cortisol at age 4 was measured using a hair sample, which provided cortisol concentration from the past months. Physical activity was measured using accelerometers at 1, 2, and 4 years. Linear regression models were used to assess the association between physical activity and chronic stress. Trajectory models were also applied to examine chronic stress in relation to physical activity patterns throughout early childhood.

RESULTS

Children with valid physical activity and hair cortisol data were included in the analyses (N = 1475). Three groups of physical activity trajectories between 1 and 4 years were identified: low, medium, and high. No association between physical activity at 1, 2, and 4 years and chronic stress at age 4 was observed. However, children in the "high" physical activity trajectory presented low cortisol concentration; the magnitude of the regression coefficient was slightly larger in girls (β = -0.125; 95% confidence interval, -0.326 to 0.074) than boys (β = -0.051; 95% confidence interval, -0.196 to 0.09).

CONCLUSION

There was no clear association between physical activity and chronic stress in early childhood. Trajectories models suggest that higher activity throughout early childhood may positively impact chronic stress; however, more studies are needed to confirm that hypothesis.

Bi-directional associations between physical activity and growth indicators of pre-school aged children

Physical activity for young children provides a wealth of benefits for health and development. However, little is known about the inter-relationship of physical activity and growth indicators. The aim of this study was to test the bi-directional associations of physical activity and growth indicators in children under five years of age. This prospective study included 1,575 children with data on physical activity and growth indicators at ages 12, 24 and 48 months. Accelerometers were used to measure physical activity. Z-scores for length/height-for-age, weight-for-length/height, weight-for-age and body mass index (BMI)-for-age were calculated. Bi-directional associations between physical activity and growth indicators were evaluated using cross-lagged panels based on Generalized Estimating Equations and cross-lagged structural equation models. Physical activity was consistently associated with lower weight-related growth indicators: BMI-for-age: β=-0.12; Weight-for-age: β=-0.11; Weight-for-length/height: β=-0.12. Higher BMI-for-age indicated lower physical activity (β=-0.06). When the exposure was lagged, the association of physical activity on weight-related growth indicators remained, but weight-related growth indicators showed a negative association on physical activity. A bi-directional association between physical activity and weight-related growth indicators was observed. The magnitude of associations were stronger when physical activity was modelled as exposure. These results reinforce the importance of physical activity since early years.

Secular trends and social inequalities in child behavioural problems across three Brazilian cohort studies (1993, 2004 and 2015)

AIMS

Previous epidemiological evidence identified a concerning increase in behavioural problems among young children from 1997 to 2008 in Brazil. However, it is unclear whether behavioural problems have continued to increase, if secular changes vary between sociodemographic groups and what might explain changes over time. We aimed to monitor changes in child behavioural problems over a 22-year period from 1997 to 2019, examine changing social inequalities and explore potential explanations for recent changes in behavioural problems between 2008 and 2019.

METHODS

The Child Behaviour Checklist was used to compare parent-reported behavioural problems in 4-year-old children across three Brazilian birth cohorts assessed in 1997 (1993 cohort, n = 633), 2008 (2004 cohort, n = 3750) and 2019 (2015 cohort, n = 577). Response rates across all three population-based cohorts were over 90%. Moderation analyses tested if cross-cohort changes differed by social inequalities (demographic and socioeconomic position), while explanatory models explored whether changes in hypothesized risk and protective factors in prenatal development (e.g., smoking during pregnancy) and family life (e.g., maternal depression and harsh parenting) accounted for changes in child behavioural problems from 2008 to 2019.

RESULTS

Initial increases in child behavioural problems from 1997 to 2008 were followed by declines in conduct problems (mean change = -2.75; 95% confidence interval [CI]: -3.56, -1.94; P < 0.001), aggression (mean change = -1.84; 95% CI: -2.51, -1.17; P < 0.001) and rule-breaking behaviour (mean change = -0.91; 95% CI: -1.13, -0.69 P < 0.001) from 2008 to 2019. Sex differences in rule-breaking behaviour diminished during this 22-year period, whereas socioeconomic inequalities in behavioural problems emerged in 2008 and then remained relatively stable. Consequently, children from poorer and less educated families had higher behavioural problems, compared to more socially advantaged children, in the two more recent cohorts. Changes in measured risk and protective factors partly explained the reduction in behavioural problems from 2008 to 2019.

CONCLUSIONS

Following a rise in child behavioural problems, there was a subsequent reduction in behavioural problems from 2008 to 2019. However, social inequalities increased and remained high. Continued monitoring of behavioural problems by subgroups is critical for closing the gap between socially advantaged and disadvantaged children and achieving health equity for the next generation.

Breastfeeding Duration and Exclusivity Among Early-Term and Full-Term Infants: A Cohort Study

Background

As compared to full-term infants (39-41 weeks of gestation), early-term infants (37-38 wk) are at increased risk of adverse outcomes, including shorter exclusive breastfeeding (EB) duration and continued breastfeeding.

Objectives

To compare early-term with full- and late-term infants regarding the prevalence of EB at 3 mo and any breastfeeding at 12 mo.

Methods

Data sets from two population-based birth cohorts conducted in the city of Pelotas, Brazil, were combined. Only term infants (37 0/7 through 41 6/7 weeks of gestation) were included in the analyses. Early-term infants (37 0/7 through 38 6/7 wk) were compared to the remaining term infants (39 0/7 through 41 6/7 wk). Information on breastfeeding was gathered through maternal interviews at the 3-mo and 12-mo follow-ups. The prevalence of EB at 3 mo and any breastfeeding at 12 mo with 95% CIs were calculated. Crude and adjusted prevalence ratios (PRs) were obtained through Poisson regression.

Results

A total of 6395 infants with information on gestational age and EB at 3 mo and 6401 infants with information on gestational age and any breastfeeding at 12 mo were analyzed. There was no difference between early-term infants and the remaining term infants regarding the prevalence of EB at 3 mo (29.2% and 27.9%, respectively) (P = 0.248). Prevalence of any breastfeeding at 12 mo was lower in early-term infants than among those born between 39 0/7 and 41 6/7 weeks of gestation (38.2% compared with 42.4%) (P = 0.001). In the adjusted analysis, the PR for any breastfeeding at 12 mo was 15% lower in the early-term group than in the remaining term infants (PR = 0.85; 95% CI: 0.76-0.95) (P = 0.004).

Conclusions

The prevalence of EB at 3 mo was similar among term infants. Nonetheless, in comparison with the remaining infants born at term, early-term infants were at increased risk of having been weaned before reaching 12 mo of age. Curr Dev Nutr 2023;xx:xx.

Influence of maternal excess weight before pregnancy on breast-feeding and weaning: pooled analyses of four population-based cohorts born between 1982 and 2015

To investigate the associations of maternal excess weight before pregnancy with (1) weaning at 3 months of age, (2) duration of exclusive breast-feeding at 6 months of age, (3) duration of any breast-feeding at 12 months of age and (4) to compare the magnitude of these associations over four decades. Data were from participants in the Pelotas (Brazil) Birth Cohorts born in 1982 (n 5334), 1993 (n 1442), 2004 (n 4092) and 2015 (n 4102). Maternal pre-pregnancy weight was collected after the delivery and breast-feeding status was assessed when children were 3 and 12 months old. Only in the most recent cohort (2015), women with excess weight (BMI ≥ 25 kg/m²) before pregnancy had higher risk of discontinuing exclusive breast-feeding within the first 6 months postpartum than women with normal weight (hazard ratio = 1·22 (95 % CI 1·15, 1·30)). Duration of any type of breast-feeding until 12 months of age was not affected by pre-pregnancy weight. Excess weight before pregnancy is associated with exclusive breast-feeding only in the most recent birth cohort coinciding with increases in excess weight and breast-feeding over time.

Maternal adverse childhood experiences (ACEs) and their associations with intimate partner violence and child maltreatment: Results from a Brazilian birth cohort

Adverse childhood experiences (ACEs) have been found to predict many negative life outcomes. However, very little evidence exists on Intimate Partner Violence (IPV) and Child Maltreatment (CM). We investigated the impact of maternal ACEs on IPV and CM in three different: cumulative risk, individual adversities and particular groupings of ACEs. The 2015 Pelotas Birth Cohort, Southern Brazil, has followed a population-based sample mothers and children repeatedly until children were aged 4 years, when mothers provided data on ACEs, and current IPV and CM. ACEs were examined in three different ways: (i) as a cumulative risk score; (ii) individual adversities; and (iii) patterns of ACEs (Latent Class Analysis: LCA). One quarter (25.4%) of mothers reported having 5+ ACEs in childhood. Compared to mothers with no ACEs, those who reported 5+ ACEs, had 4.9 (95%CI 3.5; 6.7) times the risk of experiencing IPV and 3.8 (95%CI 2.5; 5.6) times the risk of reporting child maltreatment. LCA results also highlighted the major influence of multiple ACEs on later IPV and CM. However, individual ACEs related to violence (exposure to abuse or domestic violence) showed some specificity for both later IPV and CM, over and above the influence of cumulative childhood adversity. This is the first large study to demonstrate a strong link between maternal ACEs and both IPV and CM. Cumulative ACE exposure and some specificity in effects of childhood violence are important for later IPV and CM. Integrated prevention is essential for reducing the intergenerational transmission of adversity and violence.

All are equal, but some are more equal than others: social determinants of leisure time physical activity through the lens of intersectionality

Background

To date, no research has investigated social determinants of leisure time physical activity through the lens of intersectionality in a low- and middle-income country. Therefore, the aim of this study was to explore the intersectionality in leisure time physical activity in a nationwide sample of Brazilian adults.

Methods

Data from the Brazilian National Health Survey conducted in 2013 were analysed (N = 58,429). Prevalence of sufficient leisure time physical activity (150+ minutes per week in moderate-to-vigorous physical activity) was estimated according to gender, racial identity, education and income, and according to multiple combinations of these sociodemographic characteristics (i.e., multiple jeopardy index).

Results

The prevalence of sufficient leisure time physical activity was 22.9% (95%CI: 22.3 to 23.6). Overall, the prevalence of sufficient leisure time physical activity was highest among men, individuals with white skin colour, and among those in the highest group of education and income. Among men, white, with a university degree and in the highest quartile of income (3% of the population), the prevalence of sufficient leisure time physical activity was 48%. Among non-white women with low education and low income (8.1% of the population), the prevalence of sufficient leisure time physical activity was 9.8%.

Conclusion

Informed by the theory of intersectionality, findings of this study have shown that intersections of gender, racial identity and socioeconomic position of the Brazilian society strongly influence leisure time physical activity at the individual level. Targeted interventions to increase leisure time physical activity should address the complexities of social status intersections.

Longitudinal Associations Between Device-Measured Physical Activity and Early Childhood Neurodevelopment

BACKGROUND

The aim of this study was to investigate longitudinal associations between physical activity and early childhood neurodevelopment.

METHODS

Data from 1673 children from the 2015 Pelotas (Brazil) birth cohort study were analyzed. Physical activity was measured using accelerometers on the wrist at ages 1, 2, and 4 years. Neurodevelopment was measured using the Battelle Development Inventory at age 4 years. Linear regression models were used to test trajectories and cumulative associations of physical activity with child neurodevelopment.

RESULTS

Of the 3 physical activity trajectories observed, children in the medium (β = 1.17; 95% confidence interval, 0.25 to 2.10) and high (β = 2.22; 95% confidence interval, 0.61 to 3.82) trajectories showed higher neurodevelopment scores than children in the lower activity trajectory. Cumulative analyses showed that children in the highest tertile of physical activity in all follow-ups presented a mean neurodevelopment score 4.57 (95% confidence interval, 2.63 to 6.51) higher than children in the lowest tertile in all follow-ups. All analyses showed a dose-response characteristic of association, with higher physical activity indicating higher neurodevelopment scores.

CONCLUSIONS

Physical activity may be an important predictor of neurodevelopment through early childhood.

Early onset of overweight among children from low-income families: The role of exclusive breastfeeding and maternal intake of ultra-processed food

CONTEXT

There is an increasing prevalence of overweight during early childhood in the most impoverished areas in Brazil, although there is a lack of evidence regarding its onset.

OBJECTIVES

To investigate the incidence and risk factors associated with overweight among low-income children during their first year of life.

METHODS

We analysed data from a prospective birth cohort study conducted in Brazil, which followed-up children at birth, 3rd, 6th and 12th months (n = 196). The overweight incidence (zBMI/A > 2SD) was analysed using the Kaplan-Meier survival estimator and its associated factors by the Coxs regression model. Missing data were addressed with multiple imputations and results on the final adjusted model were calculated by pooling the estimates generated for each imputed dataset.

RESULTS

The overweight incidence was 17 events/100 children-year, and most cases occurred before the 6th month. The final model showed that children exclusively breastfed up to 30 days (vs. >30 days; HR 2.68; 95%CI 1.11-6.49) and whose mothers consumed ultra-processed foods more than 4 times/day (vs. ≤4 times/day; HR 3.02; 95%CI 1.28-7.13) presented a higher risk of developing overweight.

CONCLUSION

The overweight incidence was high in this impoverished population. Shorter exclusive breastfeeding duration and an unhealthy household food environment provided a short-term risk increase.

Conditional cash transfers and adolescent mental health in Brazil: Evidence from the 2004 Pelotas Birth Cohort

BACKGROUND

Young people living in poverty are at higher risk of mental disorders, but whether interventions aimed to reduce poverty have lasting effects on mental health has not been well established. We examined whether exposure to Brazil's conditional cash transfers programme (CCT), Bolsa Família (BFP), during childhood reduces the risk of mental health problems in early adolescence.

METHODS

We used data from 2063 participants in the 2004 Pelotas Birth Cohort study. Propensity score matching (PSM) estimated the association between BFP participation at age 6 and externalising problems (Strengths and Difficulties Questionnaire - SDQ and violent behaviour) and socio-emotional competencies (Development and Well-Being Assessment questionnaire, and the Nowick-Strickland Internal-External Scale) at age 11.

RESULTS

PSM results suggest that programme participation at age of six was not significantly associated with externalising problems (P = 0.433), prosocial behaviour (P = 0.654), violent behaviour (P = 0.342), social aptitudes (P = 0.281), positive attributes (P = 0.439), or locus of control (P = 0.148) at the age of 11 years.

CONCLUSIONS

Participation in BFP during childhood was not associated with improved or worsened mental health in early adolescence. While we cannot fully discard that findings may be due to adverse selection, results suggest that CCTs alone may not be sufficient to improve mental health outcomes and would be prudent to assess whether mental health interventions as an addition to CCTs may be helpful.

Testing, Inequities and Vulnerability of Adolescents to Sexually Transmitted Infections

Sexually transmitted infections (STIs) should form part of the comprehensive healthcare agenda for adolescents and young people (A&Y) and testing plays a strategic role in STI prevention. However, little attention has been paid to the social and programmatic obstacles to this practice among A&Y. The aim of this study is to describe the prevalence of testing for syphilis and HIV reported by a group of A&Y, analyzing its relationship with variables potentially indicative of inequities related to vulnerability to STIs. This was a cross-sectional survey applied to students at public high schools in three cities in the state of São Paulo, Brazil. The responses of 369 young people who reported having started sexual life were analyzed. The analysis included description of the frequencies of demographic and socioeconomic variables and their associations with testing for syphilis and HIV through the chi-square test. The concentration index (CI) was also calculated, with construction of the respective concentration curve for the associated variables. Positive associations were found between occurrence of testing and living in homes with up to three inhabitants, living in a marital situation with a regular or committed partnership, previous use of primary care services and previous use of hospitals or emergency services. The concentration curve for testing STIs showed significant contributions from the associated variables. The findings indicated that situations of inequity need to be addressed in order to reduce A&Y's vulnerability to STIs.

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.

Physical Activity and Sitting Time From 16 to 24 Weeks of Pregnancy to 12, 24, and 48 Months Postpartum: Findings From the 2015 Pelotas (Brazil) Birth Cohort Study

BACKGROUND

Physical activity levels decrease during pregnancy, and the time course of return to prepregnancy levels is unclear. This study aimed to describe changes in leisure-time physical activity (LTPA) and sitting time from 16 to 24 weeks of pregnancy to 12, 24, and 48 months postpartum in women with different education levels in Brazil.

METHODS

Data from 4000 mothers of children enrolled in the 2015 Pelotas (Brazil) Birth Cohort were analyzed. The women were interviewed between 16 and 24 weeks of pregnancy and when their children were aged 12, 24, and 48 months. The LTPA and sitting time were self-reported.

RESULTS

Only 15.7% of the women reported any LTPA during pregnancy; this declined to 7.9% at 12 months postpartum; it was 16.8% at 24 months and 23.2% at 48 months. On average, participants spent a mean (SD) of 6.4 (3.9), 4.2 (3.2), 4.3 (3.3), and 4.4 (3.3) hours per day sitting during pregnancy, and at 12, 24, and 48 months after the birth, respectively. Both any LTPA and high sitting (8+ h/d) were consistently higher among women with higher education.

CONCLUSION

After 24 months postpartum, LTPA levels had returned to or exceeded pregnancy levels, but sitting time remained lower than during pregnancy.

Trends and inequalities in unplanned pregnancy in three population-based birth cohorts in Pelotas, Brazil

OBJECTIVES

To assess time trends in unplanned pregnancy, stratified by sociodemographic status, reproductive history, and inequalities in family income and women's skin color, in Pelotas, Brazil.

METHODS

Data from mothers of participants of the 1993 (N = 5264), 2004 (N = 4243), and 2015 (N = 4268) Pelotas birth cohorts were analyzed. Unplanned pregnancy was investigated in the perinatal period, with tests to assess changes over time among different sociodemographic and reproductive history subgroups and inequalities as a function of family income and skin color.

RESULTS

The prevalence of unplanned pregnancy was 62.7% (3299/ 5264), 65.9% (2794/ 4243), and 52.2% (2226/ 4268) in the 1993, 2004, and 2015 cohorts, respectively. Black or brown women and women of lower socioeconomic status had a higher prevalence of unplanned pregnancy in all cohorts. The overall rate of unplanned pregnancy decreased over time in most subgroups. Inequality as a function of family income and skin color increased during the time frame of assessment.

CONCLUSIONS

The prevalence of unplanned pregnancies decreased in the period analyzed, but it is still unjustifiably high. Efforts aimed at reducing unplanned pregnancy are vital and will require special attention to the most vulnerable groups.

Repeated high blood pressure at 6 and 11 years at the Pelotas 2004 birth cohort study

Background

We evaluated the prevalence and the factors associated with repeated high systolic (SBP) and diastolic blood pressure (DBP) at 6- and 11-year follow-ups of children from the Pelotas (Brazil) 2004 Birth Cohort.

Methods

All live births to mothers living in the urban area of Pelotas were enrolled in the cohort. Blood pressure (BP) values were transformed into Z-scores by sex, age, and height. High SBP and DBP were defined as repeated systolic and diastolic BP Z-scores on the ≥95th percentile at the two follow-ups. Prevalence (95% confidence interval) of repeated high SBP, DBP, and both (SDBP) were calculated. Associations with maternal and child characteristics were explored in crude and adjusted logistic regression analyses.

Results

A total of 3182 cohort participants were analyzed. Prevalence of repeated high SBP, DBP and SDBP was 1.7% (1.2–2.1%), 2.3% (1.8–2.9%) and 1.2% (0.9–1.6%), respectively. Repeated high SBP was associated with males, gestational diabetes mellitus (2.92; 1.13–7.58) and obesity at 11 years (2.44; 1.29–4.59); while repeated high DBP was associated with females, family history of hypertension from both sides (3.95; 1.59–9.85) and gestational age < 34 weeks (4.08; 1.52–10.96). Repeated high SDBP was not associated with any of the characteristics investigated.

Conclusion

Prevalence of repeated high SBP, DBP, and SDBP were within the expected distribution at the population level. Nonetheless, gestational diabetes mellitus, obesity, family history of hypertension, and prematurity increased the risk of repeated high blood pressure measured at two occasions 5 years apart.

Hospital admissions in the first year of life: inequalities over three decades in a southern Brazilian city

BACKGROUND

Hospital admissions in infancy are declining in several countries. We describe admissions to neonatal intensive care units (NICU) and other hospitalizations over a 33-year period in the Brazilian city of Pelotas.

METHODS

We analysed data from four population-based birth cohorts launched in 1982, 1993, 2004 and 2015, each including all hospital births in the calendar year. NICU and other hospital admissions during infancy were reported by the mothers in the perinatal interview and at the 12-month visit, respectively. We describe these outcomes by sex of the child, family income and maternal skin colour.

RESULTS

In 1982, NICUs did not exist in the city; admissions into NICUs increased from 2.7% of all newborns in 1993 to 6.7% in 2015, and admission rates were similar in all income groups. Hospitalizations during the first year of life fell by 29%, from 23.7% in 1982 to 16.8% in 2015, and diarrhoea admissions fell by 95.2%. Pneumonia admissions fell by 46.3% from 1993 to 2015 (no data available for 1982). Admissions due to perinatal causes increased during the period. In the poorest income quintile, total admissions fell by 33% (from 35.7% to 23.9%), but in the richest quintile these remained stable at around 10%, leading to a reduction in inequalities. Over the whole period, children born to women with black or brown skin were 30% more likely to be admitted than those of white-skinned mothers.

CONCLUSIONS

Whereas NICU admissions increased, total admissions in the first year of life declined by nearly one-third. Socioeconomic disparities were reduced, but important gaps remain.

Maternal reproductive history: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015

Background

Brazil experienced important progress in maternal and child health in recent decades. We aimed at describing secular trends as well as socioeconomic and ethnic inequalities in reproductive history indicators (birth spacing, previous adverse perinatal outcome, parity and multiple births) over a 33-year span.

Methods

Four population-based birth cohort studies included all hospital births in 1982, 1993, 2004 and 2015 in Pelotas, Southern Brazil. Information on reproductive history was collected through interviews. Indicators were stratified by family income quintiles and skin colour. Absolute and relative measures of inequality were calculated.

Results

From 1982 to 2015, the proportion of primiparae increased from 39.2% to 49.6%, and median birth interval increased by 23.2 months. Poor women were more likely to report short intervals and higher parity, although reductions were observed in all income and ethnic groups. History of previous low birthweight was inversely related to income and increased by 7.7% points (pp) over time—more rapidly in the richest (12.1 pp) than in the poorest quintile (0.4 pp). Multiple births increased from 1.7% to 2.7%, with the highest increase observed among the richest quintile and for white women (220% and 70% increase, respectively). Absolute and relative income and ethnic-related inequalities for short birth intervals increased, whereas inequalities for previous low birthweight decreased over time.

Conclusions

In this 33-year period there were increases in birth intervals, multiple births and reports of previous low-birthweight infants. These trends may be explained by increased family planning coverage, assisted reproduction and a rise in preterm births, respectively. Our results show that socioeconomic and ethnic inequalities in health are dynamic and vary over time, within the same location.

Breastfeeding exclusivity and duration: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015

Background

Brazil has made substantial improvements in the duration of breastfeeding. We use data from four population-based cohorts to examine how trends and inequalities in breastfeeding indicators changed over time in a Brazilian city.

Methods

Data from four birth cohorts, each including all births in a calendar year (1982, 1993, 2004 and 2015) in the city of Pelotas were used. Information on breastfeeding was collected when children were aged between 3 and 20 months. The prevalences of continued breastfeeding at 1 year of age and of exclusive breastfeeding at 3 months were calculated according to family income, maternal skin colour and sex.

Results

Prevalence of breastfeeding at 12 months increased from 16% to 41% in the 33-year period. The prevalence of exclusive breastfeeding at 3 months increased from 7% in 1993 to 45% in 2015. Increases in exclusive breastfeeding at 3 months were seen in all socioeconomic groups, but the 2015 rates remain highest (57.2%) among the women in the richest quintile, and lowest among those in the poorest quintile (34.6%). Black mothers were more likely to breastfeed at 12 months than Whites in the four cohorts. In the earlier cohorts, breastfeeding at 12 months was more common among the poor, but by 2015 these differences had disappeared.

Conclusions

There were important positive changes in breastfeeding practices during this period, but less than half of the children in 2015 were receiving the full benefits of breast milk. Improved breastfeeding practices are being adopted by high-income women to a greater extent than by poor women.

Infant nutrition and growth: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015

BACKGROUND

Levels of child undernutrition have declined in many middle-income countries, whereas overweight and obesity have increased. We describe time trends in nutritional indicators at age 1 year in the 1982, 1993, 2004 and 2015 Pelotas (Brazil) Birth Cohorts.

METHODS

Each study included all children born in the urban area of the city, with over 4 200 births in each cohort. Children were measured at approximately 12 months of age. Anthropometric indicators were calculated according to World Health Organization Growth Standards. Stunting and wasting were defined as <-2 Z scores for length for age and weight for length, and overweight as >2 Z scores for weight for length. Prevalence was stratified by sex, maternal skin colour and family income.

RESULTS

The prevalence of stunting declined by 53% (from 8.3% to 3.9%) from 1982 to 2015. Wasting prevalence remained stable at low levels (1.8% in 1982 and 1.7% in 2015), whereas overweight increased by 88% (6.5% to 12.2%). Undernutrition was more common among boys, those born to mothers with brown or black skin colour and in the poorest quintile of families. Socioeconomic inequalities in undernutrition decreased markedly over time. Overweight was markedly more common among the rich in 1982, but fast increase among the poor eliminated socioeconomic differences by 2015, when all groups showed similar prevalence.

CONCLUSIONS

Our results confirm the rapid nutrition transition in Brazil, with marked reduction in levels and inequalities in undernutrition in parallel with a rapid increase in overweight, which became the main nutritional problem for children.

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

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.

Antenatal care and caesarean sections: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015

BACKGROUND

Antenatal care and correctly indicated caesarean section can positively impact on health outcomes of the mother and newborn. Our objective was to describe how coverage and inequalities for these interventions changed from 1982 to 2015 in Pelotas, Brazil.

METHODS

Using perinatal data from the 1982, 1993, 2004 and 2015 Pelotas birth cohorts, we assessed antenatal care coverage and caesarean section rates over time. Antenatal care indicators included the median number of visits, the prevalence of mothers attending at least six visits and the proportion who started antenatal care in the first trimester of pregnancy and attended at least six visits. We described these outcomes according to income quintiles and maternal skin colour, to identify inequalities. We described overall, private sector and public sector caesarean section rates. Differences in prevalence were tested using chi-square testing and median differences using Kruskal-Wallis testing.

RESULTS

From 1982 to 2015, the median number of antenatal care visits and the prevalence of mothers attending at least six visits increased in all income quintiles and skin colour groups. Inequalities were reduced, but not eliminated. The overall proportion of caesarean births increased from 27.6% in 1982 to 65.1% in 2015, when 93.9% of the births in the private sector were by caesarean section. Absolute income-related inequalities in caesarean sections increased over time.

CONCLUSIONS

Special attention should be given to the antenatal care of poor and Black women in order to reduce inequalities. The explosive increase in caesarean sections requires radical changes in delivery care policies, in order to reverse the current trend.

Maternal anthropometry: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015

BACKGROUND

Pre-pregnancy nutritional status and weight gain during pregnancy have short- and long-term consequences for the health of women and children. This study was aimed at evaluating maternal height,- and overweight or obesity at the beginning of the pregnancy and gestational weight gain, according to socioeconomic status and maternal skin colour of mothers in Pelotas, a southern Brazilian city, in 1982, 1993, 2004 and 2015.

METHODS

In 1982, 1993, 2004 and 2015, the maternity hospitals in Pelotas were visited daily, all deliveries were identified and mothers who lived in the urban area of the city were interviewed. Maternal weight at the beginning of the pregnancy was self-reported by the mother or obtained from the antenatal card. Maternal height was collected from the maternity records or measured by the research team. Overweight or obesity was defined by a body mass index ≥25 kg/m2. Gestational weight gain was evaluated according to the Institute of Medicine guidelines.

RESULTS

In the four cohorts, we evaluated 19 931 women. From 1982 to 2015, the prevalence of overweight or obesity at the beginning of the pregnancy increased from 22.1% to 47.0% and height increased by an average of 5.2 cm, whereas gestational weight gain did not change. Socioeconomic status was positively associated with maternal height, and the difference between the poorest and the wealthiest decreased. Overweight or obesity was lower among those mothers in the extreme categories of family income.

CONCLUSIONS

Over the 33-year span, mothers were taller at the beginning of the pregnancy, but the prevalence of overweight or obesity more than doubled.

Stillbirth, newborn and infant mortality: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015

BACKGROUND

Infant-mortality rates have been declining in many low- and middle-income countries, including Brazil. Information on causes of death and on socio-economic inequalities is scarce.

METHODS

Four birth cohorts were carried out in the city of Pelotas in 1982, 1993, 2004 and 2015, each including all hospital births in the calendar year. Surveillance in hospitals and vital registries, accompanied by interviews with doctors and families, detected fetal and infant deaths and ascertained their causes. Late-fetal (stillbirth)-, neonatal- and post-neonatal-death rates were calculated.

RESULTS

All-cause and cause-specific death rates were reduced. During the study period, stillbirths fell by 47.8% (from 16.1 to 8.4 per 1000), neonatal mortality by 57.0% (from 20.1 to 8.7) and infant mortality by 62.0% (from 36.4 to 13.8). Perinatal causes were the leading causes of death in the four cohorts; deaths due to infectious diseases showed the largest reductions, with diarrhoea causing 25 deaths in 1982 and none in 2015. Late-fetal-, neonatal- and infant-mortality rates were higher for children born to Brown or Black women and to low-income women. Absolute socio-economic inequalities based on income-expressed in deaths per 1000 births-were reduced over time but relative inequalities-expressed as ratios of mortality rates-tended to remain stable.

CONCLUSION

The observed improvements are likely due to progress in social determinants of health and expansion of health care. In spite of progress, current levels remain substantially greater than those observed in high-income countries, and social and ethnic inequalities persist.