Printed in UJ3A. INDUCED ABORTION AND SPONTANEOUS ABORTION: NO CONNECTION?

The hypothesis that spontaneous abortion Is associated with prior Induced abortion to tested In an epldemlologlc study. The reproductive histories of a consecutive aeries of women admitted to hospital with spontaneous abor-tions were compared with those of a control series of women who delivered after 28 weeks gestation. There to no association between spontaneous abortion and prior Induced abortion. The power of the analysis to detect a 30 % excess In the frequency of Induced abortion In cases as compared to controls to 82 % at a =.05. The design and analysis effectually controlled for all potentially confounding factors. abortion, Induced; miscarriage; pregnancy This paper tests the hypothesis that spontaneous abortions are associated with prior induced abortion. Induced abortion carried out on a large scale is novel enough in any population to require careful eval-uation for all effects. Hogue (1) reviewed 10 published and unpublished reports on the relation of induced abortions to pre-maturity. Seven of these studies defined prematurity by birthweight (less than Received for publication September 19, 1977, and in final form December 6,1977.