The Institute of Medicine reports on legalized abortion and the public health. (Comment and Controversy).

Two major conclusions emerge from the year-long study by the National Academy of Sciences' Institute of Medicine about how legalized abortion affects the public health:

* "Fewer deaths and a lower rate of medical complications" may be expected when abortion legalization permits women to obtain abortions in "proper medical surroundings" than when restrictive laws and practices prevail. This is because "many women will seek to terminate an unwanted pregnancy by abortion whether it is legal or not . . . [and] the mortality and morbidity associated with illegal abortion . . . are clearly greater than the risks associated with legal abortion." The institute's report notes that 70 percent of legal abortions in the United States replace abortions that were previously obtained illegally.

* "Laws, medical practices, and educational programs should enable and encourage women who have chosen abortion to obtain it in the first three months of pregnancy," since the risks of death and illness are much greater for second-trimester than first-trimester abortions. (The report points out, however, that abortions cannot usually be performed before the second trimester when the purpose is to avert genetic abnormalities, since procedures for diagnosis of fetal defects can rarely be performed until the fifteenth week of pregnancy. The investigators emphasize the importance of research to find safer methods of inducing abortion in the second trimester.)

The report also places "highest priority" on continued investigation of long-term medical complications of induced abortion; "the effects of abortion and denied abortion on the mental health and social welfare of individuals and families"; and "factors of motivation, behavior, and access associated with contraceptive use and the choice of abortion." High priority is accorded to research on whether induced abortion "aggravates" the high risk of medical complications teenagers face from any pregnancy.

The group of scholars, researchers, health practitioners and concerned lay persons that conducted the study (*) was called together by the institute in 1974 "to review the existing evidence on the relationship between legalized abortion and the health of the public, . . . to examine the medical risks to women who obtained legal abortions," and to document changes in the risks as "the status of abortion shifts from essentially illegal to legal." (About 745,000 legal abortions were reported in the United States in 1973, and an estimated 800,000 in 1974, compared to fewer than 23,000 legal abortions in 1969, the year before passage of nonrestrictive abortion laws by four states.) The study group also closely examined the relative risks of early as compared to later abortion.

Complications from Abortion

The investigators found that the risk of early medical complications from legal abortion increases with the length of gestation. While this is true even within the first trimester, the differences are most marked between first- and second-trimester abortions; the total and major complication rate (*) is more than three times higher for abortions performed following the twelfth week, than for those performed earlier. Most of the report's conclusions on complications were drawn from the Joint Program for the Study of Abortion (JPSA) study made in the United States in 1970/1971 of 73,000 legal abortions (see Table 1).