Multiple Pregnancy: Epidemiology and Association with Maternal and Perinatal Morbidity

 

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Abstract

Twin pregnancy accounts for 2 to 4% of total births, with a prevalence ranging from 0.9 to 2.4% in Brazil. It is associated with worse maternal and perinatal outcomes. Many conditions, such as severe maternal morbidity (SMM) (potentially life-threatening conditions and maternal near-miss) and neonatal near-miss (NNM) still have not been properly investigated in the literature. The difficulty in determining the conditions associated with twin pregnancy probably lies in its relatively low occurrence and the need for larger population studies. The use of the whole population and of databases from large multicenter studies, therefore, may provide unprecedented results. Since it is a rare condition, it is more easily evaluated using vital statistics from birth e-registries. Therefore, we have performed a literature review to identify the characteristics of twin pregnancy in Brazil and worldwide. Twin pregnancy has consistently been associated with SMM, maternal near-miss (MNM) and perinatal morbidity, with still worse results for the second twin, possibly due to some characteristics of the delivery, including safety and availability of appropriate obstetric care to women at a high risk of perinatal complications.

Resumo

A gestação gemelar é responsável por 2 a 4% do total de nascimentos, com uma prevalência variando de 0,9 a 2,4% no Brasil. Ela é associada a piores resultados maternos e perinatais. Muitas condições, como a morbidade materna grave (condições potencialmente ameaçadoras da vida e near-miss materno) e near-miss neonatal ainda não foram investigadas de forma apropriada na literatura. A dificuldade na determinação de condições associadas com a gestação gemelar provavelmente reside em sua ocorrência relativamente baixa e na necessidade de estudos populacionais maiores. O uso da população total e de bancos de dados de grandes estudos multicêntricos podem então fornecer resultados sem precedentes. Considerando que esta é uma condição rara, ela é mais facilmente avaliada usando estatísticas vitais de registros eletrônicos de nascimento. Portanto, realizamos uma revisão da literatura para identificar as características da gestação gemelar no Brasil e no mundo. A gestação gemelar está consistentemente associada à morbidade materna grave, ao near-miss materno e à morbidade perinatal, com resultados ainda piores para o segundo gemelar, possivelmente devido a algumas características da atenção ao nascimento, incluindo segurança e disponibilidade de cuidados obstétricos apropriados para a mulher com alto risco de complicações perinatais.

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