Neural tube defects. Results of long-term epidemiological observation in the regions of the Russian Federation

Introduction. Neural tube defects (NTDs), being frequent and severe developmental defects, remain a significant cause of mortality and morbidity in newborns, and make a significant contribution to the structure of stillbirth causes. To plan the volumes and implement preventive measures aimed at reducing the level of NTDs, it is important to know the epidemiological characteristics of defects in the regions of the Russian Federation.

Aim: to estimate the frequency of neural tube defects in the regions of the Russian Federation based on monitoring of congenital defects.

Methods. The study included a retrospective analysis of the database of epidemiological monitoring of congenital malformations (CM), covering a 13-year period (2011-2023). The material was data from 33 regions of the Russian Federation that regularly monitor CM. The study included cases of defects among live births, stillbirths, as well as eliminated fetuses with NTDs.

Results. During the analyzed period, 7989 cases of NTDs were registered in the congenital malformations monitoring database, the total number of newborns was 6,834,020. The total incidence of NTDs was 11.69 per 10,000 births (95% CI 11.56-11.82). Among all cases of NTDs, live births accounted for 22.32%, stillbirths – 4.03%, and eliminated fetuses – 73.65%. Regional frequencies ranged from 3.25 to 19.99 per 10,000 births. In the NTD group, the most common defect is spinal bifida, while encephalocele is a rare defect. During the study period, the level of NTDs in all regions remains stable, however, in recent years (2020-2023) there has been a slight decrease in the level of NTDs, which is due to secondary prevention measures.

Conclusions. NTDs remain common congenital malformations. During the analyzed period, the frequency of this group of defects remains stable. The observed decrease in the level of NTDs among newborns is the result of second-level preventive measures. Obviously, in order to reduce the overall incidence of NTDs, it is necessary to increase the effectiveness of primary prevention (raising awareness of women of reproductive age about the possibilities of reducing risks, timely intake of folic acid).

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