Rh prevention: a report and analysis of a national programme.

A nation-wide Rh prevention programme was started in Finland in 1969. Before that, a control series of approximately 1000 Rh-negative mothers giving birth to an Rh-positive child was collected to estimate the number ofmothers with antibodies at either three, six, or nine months post partum. During the threeand-a-half year period altogether 14,980 Rh-negative patients were given 250 ,tg of anti-D immunoglobulin prepared from Finnish raw material in the Central Laboratory of the Dutch Red Cross. Out of those treated before the end of June 1972, 12,720 (97%,/) were tested four to six months post partum. Seventeen or 0.13% had detectable antibodies; in five ofthem the infant was ABO incompatible. The number of protected mothers with a subsequent Rh-positive infant was 1017; 10 had formed antibodies before the delivery of the second child. The risk of primary immunization initiated during a single pregnancy was estimated to be 0.35o/. In addition, there was approximately a 0 60% risk of forming antibodies by the next Rh-positive pregnancy. The effect of prevention on the prevalence of haemolytic disease was calculated and compared with observed figures.