It is believed that the periconceptional usage of folic acid alone or in multivitamin is effective for the prevention of congenital abnormalities. Numerous findings were supported, but not all observational studies. In case, when parents were informed that the fetus is have a defect, they have to choose between two heavy options. While to have a malformed baby with all consequences or have to terminate the pregnancy. Mostly they choose the last option, i.e. to terminate the pregnancy. Therefore, the experts have to do their best to introduce the only good solution called the primary prevention of Congenital Abnormalities. It stands for that this primary prevention is better than the termination of pregnancy after the antenatal diagnosis of fetal defects (then so called secondary prevention).
In 1990s there were two randomized clinical trials which indidicated the effectiveness of high dose of folic acid (e.g. 5 mg) or folic acid containing multivitamin supplementation during periconceptional period in the primary prevention of recurrent and first occurence of neural tube defects. Either multivitamin and folic acid can prevent congenital cardiovascular malformations. Folic acid-alone was effective in preventing of anorectal stenosis/atresia and the high dose one had effect in preventing orofacial clefts.
However, multivitamin were able to reduce obstructive defects of urinary tract, limb deficiencies and congenital pyloric stenosis. The finding stated multivitamins containing 0.4-0.8 mg of folic acid were more effective for the reduction of neural tube defects than high dose of folic acid. In other word, it reduced the overall occurence of congenital abnormalities in addition to have effect on neural-tube defects.
The significant results of studies were determined by the quality of study design and experts. The experts use large and population-based data set, including 30,054 pregnant women who received folic acid supplementation, matcing of cases with controls, good compliance by the mothers in responding to the questionaire, prospective and medically recorded data in folic acid supplementation in a certain portion of study groups, and a high validity in the diagnosis of congenital abnormalities.
As conclusion, recently we can identify some other specific Congenital Abnormalities which more appropriate for the primary prevention by multivitamins of folic acids, though further studies are needed to determine the optimal method and the possible risk reduction. For now they can recommend the dayly use of multivitamin supplement including 0.4-0.8 mg of folic acid combine with healthy diet and lifestyle for women who want to have a baby wihout neral-tube defects and Congenital Abnormalities.
The author of this journal is Andrew E. Czeizel, Foundation for the Community Control of Hereditary Diseases, 1148 Budapest, Bolgárkerék u. 3. Hungary. I served you with link to PDF Format of this journal.
