[Accuracy of gestational age assessment in Brazilian Information System on Live Birth (SINASC): a population study]

Association of interpregnancy interval with adverse pregnancy outcomes according to the outcomes of the preceding pregnancy: a longitudinal study with 4.7 million live births from Brazil

Background

Earlier studies have proposed a link between the Interpregnancy Interval (IPI) and unfavorable birth outcomes. However, it remains unclear if the outcomes of previous births could affect this relationship. We aimed to investigate whether the occurrence of adverse outcomes-small for gestational age (SGA), preterm birth (PTB), and low birth weight (LBW)-at the immediately preceding pregnancy could alter the association between IPI and the same outcomes at the subsequent pregnancy.

Methods

We used a population-based linked cohort from Brazil (2001-2015). IPI was measured as the difference, in months, between the preceding birth and subsequent conception. Outcomes included SGA (<10th birthweight percentile for gestational age and sex), LBW (<2500 g), and PTB (gestational age <37 weeks). We calculated risk ratios (RRs), using the IPI of 18-22 months as the reference IPI category, we also stratified by the number of adverse birth outcomes at the preceding pregnancy.

Findings

Among 4,788,279 births from 3,804,152 mothers, absolute risks for subsequent SGA, PTB, and LBW were higher for women with more adverse outcomes in the preceding delivery. The RR of SGA and LBW for IPIs <6 months were greater for women without previous adverse outcomes (SGA: 1.44 [95% Confidence Interval (CI): 1.41-1.46]; LBW: 1.49 [1.45-1.52]) compared to those with three previous adverse outcomes (SGA: 1.20 [1.10-1.29]; LBW: 1.24 [1.15-1.33]). IPIs ≥120 months were associated with greater increases in risk for LBW and PTB among women without previous birth outcomes (LBW: 1.59; [1.53-1.65]; PTB: 2.45 [2.39-2.52]) compared to women with three adverse outcomes at the index birth (LBW: 0.92 [0.78-1.06]; PTB: 1.66 [1.44-1.88]).

Interpretation

Our study suggests that women with prior adverse outcomes may have higher risks for adverse birth outcomes in subsequent pregnancies. However, risk changes due to differences in IPI length seem to have a lesser impact compared to women without a prior event. Considering maternal obstetric history is essential in birth spacing counseling.

Funding

Wellcome Trust225925/Z/22/Z.

Association between preterm births and socioeconomic development: analysis of national data

Background

The increasing prevalence of preterm birth, which is a global phenomenon, is attributable to the increased medical indications, artificial gestations, and some socioeconomic factors. This study was conducted to identify whether development and equality indices are associated with the incidence of preterm birth, specifically, spontaneous and elective preterm births.

Methods

This retrospective observational study comprised an analysis of data on live births from 2019 in Brazil and on socioeconomic indices that were derived from census information in 2017. Data were summarised using absolute and relative frequencies. Spearman’s correlation was used to determine the correlation between socioeconomic factors and the preterm birth rate. Multiple beta regression analysis was performed to determine the best model of socioeconomic covariates and preterm birth rate. The significance level was set at 5%.

Results

In 2019 in Brazil, the preterm birth rate was 11.03%, of which 58% and 42% were spontaneous and elective deliveries, respectively. For all preterm births, Spearman’s correlation varied from ρ = 0.4 for the Gini Index and ρ =  − 0.24 for illiteracy. The best fit modelled the spontaneous preterm birth fraction as a negative function of the Human Development Index (HDI). The best-fit model considered the expected elective preterm birth fraction as a positive function of the HDI and as a negative function of the Gini Index, which was used as a precision parameter.

Conclusions

We observed a reduction in the fraction of spontaneous preterm births; however, the distribution was not uniform in the territory: higher rates of spontaneous preterm birth were noticed in the north, northeast, and mid-west regions. Thus, areas with lower education levels and inequal income distribution have a higher proportion of spontaneous preterm birth. The fraction of elective preterm birth was positively associated with more advantaged indices of socioeconomic status.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14376-2.

Effect of Prematurity and Temperament on the Mother-Infant Interaction

Abstract We evaluated the effect of prematurity and the infant’s temperament on the mother-infant behaviors in the Face-to-Face Still-Face Paradigm (FFSF). The study included 75 mothers and their infants (37 preterm and 38 term) between three and four months of age (corrected age for preterm infants). The mothers responded to a perception scale of the infants’ temperament and the dyads were observed in a structured condition (FFSF). The FFSF Paradigm, divided into three episodes, made it possible to analyze the behaviors of: Positive Social Orientation, Negative Social Orientation and Self-comfort. The averages recorded for these categories were analyzed in a Multivariate ANOVA (factors: prematurity and temperament). Temperament had more effect on maternal and infant behaviors, suggesting that this factor may influence mother-infant interaction. The results can guide possible interventions with families.

Brazilian Maternal and Child Nutrition Consortium: establishment, data harmonization and basic characteristics

Pooled data analysis in the field of maternal and child nutrition rarely incorporates data from low- and middle-income countries and existing studies lack a description of the methods used to harmonize the data and to assess heterogeneity. We describe the creation of the Brazilian Maternal and Child Nutrition Consortium dataset, from multiple pooled longitudinal studies, having gestational weight gain (GWG) as an example. Investigators of the eligible studies published from 1990 to 2018 were invited to participate. We conducted consistency analysis, identified outliers, and assessed heterogeneity for GWG. Outliers identification considered the longitudinal nature of the data. Heterogeneity was performed adjusting multilevel models. We identified 68 studies and invited 59 for this initiative. Data from 29 studies were received, 21 were retained for analysis, resulting in a final sample of 17,344 women with 72,616 weight measurements. Fewer than 1% of all weight measurements were flagged as outliers. Women with pre-pregnancy obesity had lower values for GWG throughout pregnancy. GWG, birth length and weight were similar across the studies and remarkably similar to a Brazilian nationwide study. Pooled data analyses can increase the potential of addressing important questions regarding maternal and child health, especially in countries where research investment is limited.

Trend and factors associated with adverse birth weight in Uruguayan children between 2009 and 2015

Abstract Objectives: to identify trendand factors associated with adverse birth weight. Methods: cross-sectional design. The analysis uses the 2009-2015 Uruguay Perinatal Computer Systemdata on 303,625 newborns. Results: the prevalence of macrosomia (> 3,999g) has increased from 7.0% to 8.4%. The prevalence of low birth weight (LBW) (< 2,500g) decreased, standing at 6.6% in the last year. The factors that determines more possibilities of LBW were preeclampsia (OR = 4.80; CI95%= 4.57-5.05), inadequate controls (OR = 2.29; CI95%= 2.20-2.39), shorter duration of pregnancy (OR = 2.52; CI95%= 2.50-2.55), previous hypertension (OR = 2.11; CI95%= 1.96-2.27), hypertensive disease of pregnancy (OR = 1.82; CI95%= 1.74-1.90), low prematernal maternal weight (OR = 1.65; CI95%= 1.58-1.74). Macrosomia was associated with type 1 diabetes (OR = 2.21; CI95%= 1.86-2.61), Type 2 or Gestational (OR = 1.78; CI95%= 1.70-1.87), obesity maternal (OR = 2.33; CI95%= 2.24-2.43) and longer gestation duration (OR = 2.62; CI95%= 2.53-2.72). Conclusions: the LBW decreases while the macrosomia increases. The health and nutritional status of women at the beginning of pregnancy, pathologies of the last trimester, smoking, shorter duration of pregnancy and inadequate controls are associated with BPN. Overweight, obesity and metabolic diseases determine macrosomia.