Resumo

CHAVEZ-CORRAL, D. V. et al. Relation Between Levls of Folic acid, Vitamin B12 and Maternal Homocysteine with Neural Tube Defects and Cleft Lip. Int. J. Morphol. [online]. 2008, vol.26, n.4, pp. 905-914. ISSN 0717-9502.  doi: 10.4067/S0717-95022008000400020.

Objective: To determine the association between maternal folate deficieney, neural tube defeets (NTDs), and cleft lip, with and without cleft palate (CL/P). Material and methods: A case/control study was conducted. The cases included subjeets with diagnoses of NTD and CL/P (n=36) and four hospital controls per case (n=141); the study included newborns (NBs) and nursing babies upto 12monthsof age. The parameter variables were the foliowing: the age of the NB or nursing baby, the ethnic group, and the hospital of origin. The Tarahumara ethnic group made up 23% of the cases, while 77% were mestizos. The red cell folate (RCF), the plasma folie acid (PFA), and the vitamin B₁₂ levéis were determined by radioimmunoassay and the homocysteine levéis by polarized fluorescence immunoassay. A deficieney was considered to be present if the RCF were <160 ng/mL, the PFA <3.5 ng/mL and the vitamin B <200 pg/ mL; hyperhomocysteinemia was defined as HC >15 |J,mol/L. The statistical analysis was carried out through of conditional logistic regression. Results: An RCF deficieney was identified in 22% of the women whose newborn or nursing babies presented with some type of congenital defect and in 12% of the controls. The correlation adjusted by maternal age, exposure to pesticides and zone of residence was OR 2.96 (CI 95% 0.92-9.46). There was no difference in vitamin B₁₂ or homocysteine levéis between groups. Conclusions: Our results suggest that newborns whose mothers present with an RCF deficieney have an increased risk of displaying NTD and CL/P.

Palavras-chave : Defeets neural tube; Cleft lip; Cleft palate; Folie acid; Homocysteine; Vitamin B₁₂.