We report the early growth and neurologic findings of 48 infants in Brazil diagnosed with probable congenital Zika virus syndrome and followed to age 1–8 months. Most of these infants had microcephaly (86.7%) and craniofacial disproportion (95.8%). The clinical pattern included poor head growth with increasingly negative z-scores, pyramidal/extrapyramidal symptoms, and epilepsy.

OBJETIVO: Identificar as principais características socioeconômicas, demográficas, antropométricas e comportamentais, bem como os resultados perinatais da gravidez na adolescência. Conhecer os tipos de serviços de saúde utilizados pelas gestantes adolescentes. MÉTODOS: A amostra de 2.429 partos de mulheres residentes em São Luís, MA, abrangeu 94% dos nascimentos hospitalares. As mulheres foram separadas em seis grupos de idade para melhor avaliação do comportamento das variáveis entre os dois grupos de adolescentes (abaixo de 18 anos; 18 a 19 anos) e entre as adolescentes e as demais mulheres. O teste do qui-quadrado foi utilizado para a comparação de proporções e a razão de prevalências foi empregada como medida de efeito. RESULTADOS: Das 2.429 mulheres, 714 eram adolescentes (29,4%). Seu coeficiente específico de fecundidade, 72,2 por mil, foi mais elevado que em outras regiões do País. As adolescentes apresentaram piores condições socioeconômicas e reprodutivas que as demais mulheres, maior proporção de pré-natal inadequado (39,2%) e muitas não tinham companheiro (34,5%). Por outro lado, tiveram menor proporção de parto cesáreo (23,0%) e de fumantes (3.5%). CONCLUSÕES: Apesar da situação socioeconômica igualmente desfavorável, as adolescentes de 18 a 19 anos apresentaram resultados perinatais semelhantes às mulheres de 25 a 29 anos. Já as menores de 18 anos tiveram maiores proporções de filhos com baixo peso ao nascer, prematuros e com maior risco de mortalidade infantil. Isto sugere que a imaturidade biológica possa estar associada a maiores taxas de prematuridade, baixo peso ao nascer e mortalidade infantil.

The association between young maternal age and preterm birth (PTB) remains controversial. In some studies the association disappeared after controlling for socio-economic and reproductive factors, thus indicating that social disadvantage rather than biological factors may be the explanation. However, in other studies the association persisted after adjustment. The relation between young maternal age and PTB was studied in a city located in Brazil, an underdeveloped country, where the prevalence of teenage pregnancy was high, 29%. A systematic sampling of 2541 hospital births, stratified by hospital, was performed in São Luís, Northeast Brazil, from March 1997 to February 1998. The risks of PTB for infants born to two groups of young mothers (<18 and 18-19 years) were calculated with and without adjustment for confounding factors (family income, marital status, mode of delivery, parity, health insurance, and short maternal stature) in a logistic regression model, using mothers 25-29 years of age as the reference group. In the unadjusted analysis, the risk of PTB was higher for mothers < 18 years [odds ratio (OR) = 2.42, 95% confidence interval (CI) 1.64, 3.57]. Those aged 18 or 19 years were not at a higher risk of PTB (OR = 0.89, 95% CI 0.58, 1.38). After adjustment, the risk of PTB for mothers < 18 years was lower but remained significant after controlling for confounding (OR = 1.70, 95% CI 1.11, 2.60). After performing a stratified analysis according to parity, the risk of PTB among very young primiparae (<18 years) remained significant (OR = 1.77, 95% CI 1.02, 3.08), whereas the risk among non-primiparous adolescents was not significantly higher than the risk among mothers in the reference group. This suggests that the association between young maternal age and PTB may have a biological basis or an artifactual explanation (errors in gestational age estimation may be more common among very young mothers) or may be due to residual confounding.

Caesarean section (CS) delivery is associated with low birthweight (LBW) in south-east Brazil. A hospital-based study was conducted on singleton infants from mothers residing in São Luís, to assess if an association between CS and LBW was found in the northern part of the country, where the CS rate is lower than in the south-east. A standardised questionnaire was administered to a sample of 2541 mothers in 10 hospitals, representing 94% of all deliveries, from March 1997 to February 1998. In a logistic model, type of delivery was the independent variable, the other variables were treated as confounders, and interaction terms were added between type of delivery and all other factors. LBW was associated with low maternal height, maternal smoking, primiparity, previous LBW, public insurance, preterm birth and CS. The CS rate was 33.7%. The risk of CS was higher for primiparous and married mothers, those with high level of schooling and attended by the same physician during prenatal and delivery care, deliveries held in private hospitals, daylight hours or evenings, and for those mothers who had adequate prenatal care. Because it appears unlikely that only medical reasons are operative, it is a possibility that CS could cause LBW, reflecting abusive indications for elective CS.

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.