Impact of genetic counseling: a review of published follow-up studies.

Retrospective follow-up studies on the impact of genetic conseling, published since 1970, are reviewed in the present paper. Particular attention has been paid to evaluation of understanding of genetic information, planning of later pregnancies and real changes in family composition. A rather wide divergence was found with regard to these three parameters, probably more related to the design of the studies than to a divergence in counselees' understanding and decisions, emphasizing that more, and especially more methodologically sound studies are necessary to evaluate the impact of genetic counseling.