Neural tube defects in eastern Turkey; Is low folate status or vitamin B12 deficiency or both associated with a high rate of NTDs?

The aim of this study was to compare the rates of low folate status and vitB12 deficiency between pregnancies with a NTD-affected fetus and those with a structurally normal fetus in a low-income population residing in eastern Turkey. It was a retrospective cohort study conducted in our perinatology unit in eastern Turkey between 2016 and 2018. The inclusion criterion for the study group was pregnancies with an NTD-affected fetus. The control group was pregnancies who met the following criteria; no prior history of pregnancy with a NTD-affected fetus, spontaneous abortion or stillbirth, no fetal growth problems or structural abnormality in the present pregnancy, and matching by gestational age. Venous blood samples of these women were obtained at the time of ultrasound examination and serum folate and vitB12 levels were measured by chemiluminescence method using ECLIA immunologic test (Roche, cobas e601/602 analyzers) at our laboratory. The rate of NTDs was 130 per 10 000 (151/11 552). VitB12 deficiency was found in 62.9% of the study group and 36.4% of the control group ( <  .001). The rate of low folate status was also different between the groups, with 42.3 and 15.2%, respectively ( <  .001). Of the NTDs cases, 12.5% had only low folate status, 33.7% had only vitB12 deficiency, and 29.8% had both together. The rate of low folate status together with vitB12 deficiency was significantly different between the groups ( <  .001). Low folate status coupled with B12 deficiency seems to be strongly associated with NTDs. Thus, simultaneous correction of their levels may be the best reasonable approach for the prevention of NTDs in low-income regions. This strategy can reduce the rate of NTDs in low-income regions, improve overall population health and mitigate the economic burden of NTDs on health care system.