Association between prenatal care adequacy indexes and low birth weight outcome / Associação entre índices de adequação de cuidado prénatal e desfecho de baixo peso ao nascer

Abstract Objective To investigate the association between prenatal care (PNC) adequacy indexes and the low birth weigth (LBW) outcome. Methods A total of 368,093 live term singleton births in the state of Rio de Janeiro (Brazil) from 2015 to 2016 were investigated using data from the Brazilian Live Birth Information System (Sistema de Informações sobre Nascidos Vivos, SINASC, in Portuguese). Seven PNC adequacy indexes were evaluated: four developed by Brazilian authors (Ciari Jr. et al., Coutinho et al., Takeda, and an index developed and used by the Brazilian Ministry of Health - MS) and three by authors from other countries (Kessner et al., the Adequacy of Prenatal Care Utilization index - APNCU, and the Graduated Prenatal Care Utilization Index - GINDEX). Adjusted odds ratios were estimated for the PNC adequacy indexes by means of multivariate logistic regression models using maternal, gestational and newborn characteristics as covariates. Results When the PNC is classified as "inadequate", the adjusted odds ratios to the LBWoutcome increase between 42% and 132%, depending on which adequacy index is evaluated. Younger (15 to 17 years old) and older (35 to 45 years old) mothers, those not married, of black or brown ethnicity, with low schooling (who did not finish Elementary School), primiparous, with preterm births, as well as female newborns had increasing odds for LBW. The models presented areas under the receiver operating characteristic (ROC) curve between 80.4% and 81.0%, and sensitivity and specificity that varied, respectively, between 57.7% and 58.6% and 94.3% and 94.5%. Conclusion Considering all PNC adequacy indexes evaluated, the APNCU had the best discriminatory power and the best ability to predict the LBW outcome.

Resumo Objetivo Investigar a associação entre diferentes índices de adequação do cuidado pré-natal (PN) e o desfecho de nascimentos com baixo peso (BP). Métodos Foram investigados 368.093 nascimentos ocorridos no estado do Rio de Janeiro entre 2015 e 2016, utilizando-se as informações do Sistema de Informações sobre Nascidos Vivos (Sinasc). Sete índices de adequação do cuidado PN foram avaliados: quatro propostos por autores nacionais (Ciari Jr et al., Coutinho et al., Takeda, e um índice atualmente em uso pelo Ministério da Saúde - MS), e três, por autores internacionais (Kessner et al., Adequacy of Prenatal Care Utilization index - APNCU, e Graduated Prenatal Care Utilization Index - GINDEX). As razões de chance ajustadas para BP foram estimadas considerando os índices de adequação do cuidado PN por meio de modelos de regressão logística, utilizando características maternas, da gravidez e do recém-nascido como variáveis de controle. Resultados As chances ajustadas para ocorrência de BP ao nascer aumentam de 42% a 132%, a depender do índice empregado, quando o cuidado PN é considerado inadequado. Mães entre 15 e 17 anos e entre 35 e 45 anos, sem companheiro, de cor parda ou preta, com ensino fundamental incompleto, e primíparas, com gestações pré-termo, além de bebês do sexo feminino são fatores de risco para os nascimentos com BP. Conclusão Entre os índices avaliados, o APNCU foi o que apresentou melhor poder discriminatório e capacidade de prever o desfecho de BP ao nascer.

Congenital Heart Defects and the Risk of Spontaneous Preterm Birth.

OBJECTIVES: To estimate the association between major types of congenital heart defects (CHD) and spontaneous preterm birth, and to assess the potential underlying mechanisms. STUDY DESIGN: This nationwide, registry-based study included a cohort of all singleton pregnancies in Denmark from 1997 to 2013. The association between CHD and spontaneous preterm birth was estimated by multivariable Cox regression, adjusted for potential confounders. The following potential mechanisms were examined: maternal genetics (sibling analyses), polyhydramnios, preterm prelabor rupture of membranes, preeclampsia, and indicators of fetal and placental growth. RESULTS: The study included 1 040 474 births. Compared with the general population, CHD was associated with an increased risk of spontaneous preterm birth, adjusted hazard ratio 2.1 (95% CI, 1.9-2.4). Several subtypes were associated with increased risks, including pulmonary stenosis combined with a septal defect, 5.2 (95% CI, 3.7-7.5); pulmonary stenosis or atresia, 3.1 (95% CI, 2.4-4.1); tetralogy of Fallot 2.5 (95% CI, 1.6-3.8); coarctation or interrupted aortic arch 2.2 (95% CI, 1.5-3.2); and hypoplastic left heart syndrome, 2.0 (95% CI, 1.0-4.1). Overall, preterm prelabor rupture of membranes mediated more than one-half of the association. Maternal genetics, polyhydramnios, or indicators of fetal or placental growth did not explain the reported associations. CONCLUSIONS: CHD, especially right ventricular outflow tract obstructions, were associated with an increased risk of spontaneous preterm birth. The risk was carried by the CHD and not by maternal genetics. Moreover, preterm prelabor rupture of membranes was identified as a potential underlying mechanism.

Are fetal growth impairment and preterm birth causally related to child attention problems and ADHD? Evidence from a comparison between high-income and middle-income cohorts.

BACKGROUND: Cross-cohort comparison is an established method for improving causal inference. This study compared 2 cohorts, 1 from a high-income country and another from a middle-income country, to (1) establish whether birth exposures may play a causal role in the development of childhood attention problems; and (2) identify whether confounding structures play a different role in parent-reported attention difficulties compared with attention deficit hyperactivity disorder (ADHD) diagnoses. METHODS: Birth exposures included low birth weight (LBW), small-for-gestational age (SGA), small head circumference (HC) and preterm birth (PTB)). Outcomes of interest were attention difficulties (Strengths and Difficulties Questionnaire, SDQ) and ADHD (Development and Well-Being Assessment, DAWBA). Associations between exposures and outcomes were compared between 7-year-old children from the Avon Longitudinal Study of Parents and Children (ALSPAC) in the UK (N=6849) and the 2004 Pelotas cohort in Brazil (N=3509). RESULTS: For attention difficulties (SDQ), the pattern of association with birth exposures was similar between cohorts: following adjustment, attention difficulties were associated with SGA (OR=1.59, 95% CI 1.20 to 2.19) and small HC (OR=1.64, 95% CI 1.11 to 2.41) in ALSPAC and SGA (OR=1.35, 95% CI 1.04 to 1.75) in Pelotas. For ADHD, however, the pattern of association following adjustment differed markedly between cohorts. In ALSPAC, ADHD was associated with LBW (OR=2.29, 95% CI 1.09 to 4.80) and PTB (OR=2.33, 95% CI 1.23 to 4.42). In the Pelotas cohort, however, ADHD was associated with SGA (OR=1.69, 95% CI 1.02 to 2.82). CONCLUSIONS: The findings suggest that fetal growth impairment may play a causal role in the development of attention difficulties in childhood, as similar associations were identified across both cohorts. Confounding structures, however, appear to play a greater role in determining whether a child meets the full diagnostic criteria for ADHD.