The Hungarian total (birth + fetal) prevalences of different developmental abnormalities offer a possibility to estimate the proportion of preventable development abnormalities. The effectiveness of primary, secondary and tertiary preventive methods are evaluated with a particular emphasis of primary prevention based on periconceptional folic acid or folic acid-containing multivitamin supplementation. The total prevalence of informative offspring with developmental abnormalities is 66.83 per 1,000 in Hungary and within this major DAs have 27.01 per 1,000 rate. The latter can be reduced by 26.6% by primary preventive methods due to mainly periconceptional folic acid/multivitamin supplementation. Secondary prevention particularly neonatal orthopedic screening is very effective for deformities such as congenital dislocation of the hip. Antenatal diagnoses followed by termination of pregnancy can avoid the birth of malformed newborn infants in 8.7% of DAs, however, this figure is 20 and 27% among major and multiple developmental abnormalities, respectively. Early surgical intervention can achieve a complete recovery in 33.5% of cases with developmental abnormalities. Thus there are two major conclusions: at present the major part of developmental abnormalities are preventable, however, different developmental abnormalities do not represent a single pathological category therefore there is no single strategy for their prevention.