MTHFR, which actually does not allow the conversion of folic acid into active folate or metylfolate. Thus a folate deficiency is determined. This deficit can be replaced by taking supplements. Folate is recommended by the CDC and AGOC in all women of reproductive age to reduce the risk of spina bifida and neural tube defects. [1]

If the woman is going to perform IVF, it is recommended that she take more than 800mcg of folate. This recommendation is based on studies showing a correlation between micronutrient supplementation and higher chances of IVF success.[2] Besides increasing the chances of getting pregnant, folate also increases the chances of keeping it.

Sources:

1. Gaskins AJ, Mínguez-Alarcón L, Fong KC, et al. Supplemental Folate and the Relationship Between Traffic-Related Air Pollution and Livebirth Among Women Undergoing Assisted Reproduction. Am J Epidemiol. 2019;188(9):1595-1604. doi:10.1093/aje/kwz151
2. Chiu YH, Chavarro JE, Souter I. Diet and female fertility: doctor, what should I eat?. Fertil Steril. 2018;110(4):560-569. doi:10.1016/j.fertnstert.2018.05.027