Anencephaly is a congenital anomaly of multifactorial origin. The role played by genetic factors has not been elucidated so far. Nutritional factors are unquestionably also involved. The best advice that can be given to women in order to prevent the occurrence of this type of anomaly during a later pregnancy is to take one tablet of multivitamins and 1 to 2 mg of folic acid every day, starting as soon as one attempts to become pregnant and continuing until the end of pregnancy. Preferably, the multivitamin tablet and the folic acid should have been taken for 1-2 months before the pregnancy starts. There is, if this treatment is adhered to, little risk that anencephaly should complicate your wife's following pregnancies.