The relationship between some neonatal and maternal factors during pregnancy with the prevalence of congenital malformations in Iran: a systematic review and meta-analysis.

Introduction

Congenital malformations are one of the main causes of death and disability in children. These malformations arise during embryogenesis and fetal development during pregnancy due to exposure to some environmental factors and genetic mutations. Given the high prevalence of congenital malformations in Iran, the current study was conducted to investigate the relationship between some neonatal and maternal factors during pregnancy with the prevalence of congenital malformations in Iran.

Methods

This was a systematic review and meta-analysis study. All studies conducted in Iran were extracted between 2000 and 2016 during a search in internal and external databases of Medlib, Medline, Pubmed, Web of Science, Google Scholar, Scopus, Magiran, SID, Cochrane, Irandoc, and all articles published. Then, the required data were entered into the Spss16 software (SPSS Inc., Chicago, IL); and the model of fixed and random effects was analyzed in meta-analysis, Cochran, meta-regression using statistical tests.

Results

A total of 30 studies with a sample size of 928,311 patients were enrolled. Baby's gender (1-1.55: CI95%) OR: 1.25, preterm delivery (1.71-3.69: CI 95%) OR: 2.51, low birth weight (1.13-2.67: CI95%) OR: 1.74, age older than 35 for the pregnant mother (1.41-6.3: CI 95%) OR: 2.98, multiple births (1.14-3.46: CI 95%) OR: 1.99, mother suffering from chronic diseases (1.68-3.31: CI 95%) OR: 2.36 are significantly related with the risk of congenital malformations.

Conclusion

Based on the results the baby's gender, premature birth, low birth weight, mother's age, consanguineous marriages, multiple births, family history of congenital malformations, and the risk of chronic diseases in the mother during pregnancy increase the birth of children with congenital malformations. As a result, control or modification of the above factors implementing a health and education intervention program can reduce the birth of children with congenital malformations.