Birth Prevalence of Neural Tube Defects in Iran: A Systematic Review

Abstract

Context: Neural tube defects (NTDs) are one of the most common birth defects with a high rate of mortality. Several studies have shown the reduction of the rate of NTD due to preconceptional usage and flour fortification with folic acid. Objectives: The aim of this systematic literature review was to assess the appropriate information about the prevalence of Neural Tube Defects among the Iranian population, geographic areas of Iran. Data Sources: We searched PubMed, Embase, Scopus, and data banks in Iran, such as the scientific information database (SID), Magiran, and Barekat knowledge network system from January 1969 to February 2017. The following keywords were used to search all fields in the above databases ("Neural Tube Defects" OR "NTD" AND "Iran"). Study Selection: NTDs were classified as given by Moore to include anencephaly, spina bifida, encephalocele, iniencephaly, and craniorachischisis. Primary outcomes of interest for estimating the prevalences were the total number of births (including live and stillbirths if available separately) and the total number of NTD affected births (including live and stillbirths if available separately). Data Extraction: Data extracted from selected studies, included: first author, study design, city, sample size, duration of studies, and the prevalence of NTDs and subtypes of neural tube defects. Results: A total of 429 studies were initially identified in the databases. After excluding duplicate studies, 244 articles were retrieved and reviewed based on their titles and abstracts; 221 articles were excluded. Twenty-three articles were selected for a more detailed review.

Neural tube defects: A retrospective study of 69 cases

“…The incidence of NTDs is specified by genetic and environmental factors and may vary depending on factors including the country's developmental status, race, baby's gender, and family's socioeconomic and education status. [910]…”

“…The incidence of NTDs is specified by genetic and environmental factors and may vary depending on factors including the country's developmental status, race, baby's gender, and family's socioeconomic and education status. [9,10] The incidence of NTDs has been reported to be 0.89-0.93 in 1000 live births in the European countries, [11] 0.53 in the USA, [12] 0.2-9.6 in Latin America, [13] and 0.62-13.8 in the Arab countries. [14] In our country, the incidence of NTD has been reported to be 5.6 [15] and 22.6 [16] in 1000 live births in various studies.…”

Prevalence of folic acid supplement consumption before and during pregnancy, and its determinants among community health center referrals

“…Folic acid deficiency during pregnancy may lead to health problems in mothers, such as anemia and peripheral neuropathy, and in infants, including congenital abnormalities [2] and neural tube defects (NTDs) [3]. There are various risk factors for NTDs including poor maternal nutritional status and maternal folate deficiency during pregnancy [4]. Supplementation with folic acid has, therefore, been identified as a factor in decreasing NTDs in infants [5678910].…”