A review of some effects of recent medical practices in reducing the numbers of children born with congenital abnormalities.

Attempts to reduce the number of children born with congenital malformations may be seen as part of the programmes for rubella immunization and for screening for neural tube defects and chromosome anomalies. The rubella immunization programme in England and Wales has not been accompanied by any appreciable decline in the overall incidence of heart or eye malformations detected at or soon after birth. However, the decline in the incidence of babies born with defects of the central nervous system, and of babies born with Down's syndrome to elderly mothers, indicates that interventive methods of control are achieving changes.