A Study on The Incidence of Neural Tube Defects in A Tertiary Care Hospital Over A Period of Five Years.

INTRODUCTION: Several congenital malformations affect developing fetuses, among which Neural tube defect (NTD) is most common. Folic acid supplementation brought decline in the incidence of NTDs. The present study aims at finding the incidence of NTDs in a tertiary care hospital and compares the results with the similar Indian studies published earlier.

MATERIALS AND METHODS: The study was done at Chettinad Hospital & Research Institute (CHRI), Kelambakkam. The total number of deliveries was recorded for a period of five years from 2009 to 2013. Fetuses which were still born with neural defect were collected and observed in detail externally for the sex, type of NTD and other associated anomalies. Indian studies published between 1987 and 2014 reporting the incidence of NTDs among the births occurred were retrieved from the Internet and their various observations were used for comparison.

RESULTS: The number of deliveries conducted between 2009 and 2013 at CHRI was 3220. Of these, babies born with NTDs were nine (5 males and 4 females). The incidence of fetuses with meroanencephaly, holoanencephaly, craniorachischisis, encephalocele and myelocele were 0.62, 0.62, 0.93, 0.31 and 0.31 per 1000 births respectively. Overall incidence of NTDs in the present study was 2.79/1000 births. Fetuses with NTDs also had the following anomalies - Club foot, cleft lip and palate and exomphalos.

CONCLUSION: Comparing the results with the previous studies it is clearly evident that the incidence of NTDs have significantly reduced from 11.42/1000 births to 2.79/1000 births. In most of the previous studies NTDs had a female preponderance whereas present study has a male preponderance.In older studies, spina bifida was the most common NTDs followed by anencephaly. But in the present study anencephaly was the common NTD than spina bifida. Incidence of NTDs has reduced due to various reasons like prenatal screening for fetal anomalies and folic acid supplementation.